As a retired Aerospace/Aeronautical Engineer with 40+ years of experience, I am 99% certain that the Titanium Flange to Titanium Carbon-Fiber hull joint was the Achilles heel of the design. Primarily due to thermal and pressure expansion/contraction rate differences between the two materials. Joint failure was inevitable.
@JoediyLab
Жыл бұрын
Thanks for the valid insight.
@rael5469
Жыл бұрын
Amen brother. I had some composite training and even at the technician level I can see where the flexing of the glued joint is going to cause a disbond. Repeated flexing under pressure will cause it to disbond. I don't think I've seen a structural joint between composite and metal that didn't include fasteners. @terrymichael5821 could they have held the two end caps to the tube by using rods between the end caps? A minimum of four I would think. Would it have made a difference or kept the tube from collapsing? I think the tube would have collapsed eventually anyway. Tube bad. Sphere good.
@rcampbell4967
Жыл бұрын
I certainly do not have your experience or credentials, but I've been saying the same thing. There are 3 materials; carbon fiber, titanium, and the adhesive. You don't need to be an engineer to understand every material reacts differently to moisture, temperature, and pressure. Stress due to deflection or the relative lack of was put on this joint with every dive and then again at every surfacing. This stress can cause tiny defects to the adhesion starting with the first dive. These defects will likely grow exponentially with each cycle until catastrophic failure is experienced. Or, the carbon fiber delaminated and shettered with such force it harmonically broke completely free of the bonding agent. Either scinario could make sense from my understanding of the 'transcript' leaked.
@gailmcn
Жыл бұрын
A lot of professionals are diagnosing the cause of this catastrophe prior to any formal investigation of the physical evidence. Which I believe is a cardinal sin in any engineering field. Furthermore, these professionals also diagnose according to what they are most familiar with in their own specialty of the broader field. So when they hear hoofbeats outside their bedroom window, they think 'donkey', instead of 'horse', just because they know a bit more about donkeys. But there are several options here for failure, so until the investigation documents are published......
@AORD72
Жыл бұрын
Do you think there could have been a slow leak initially?
@bigjared8946
Жыл бұрын
The bonding method itself is dubious but the way they were doing it in a warehouse and not a cleanroom is wow.
@JoediyLab
Жыл бұрын
Yes, also the guy in the video wiping the ring/flange did not have gloves on.
@bigjared8946
Жыл бұрын
@@JoediyLab Stockton: It's not like Elmer's glue, it's like peanut butter. I'm convinced this guy's family paid for his engineering degree, which is a thing that needs more scrutiny because "engineers" like that will kill people.
@gaylecheung3087
Жыл бұрын
Leaving oils from your finger is your hands and not in a clean environment with suits and mask gloves
@SteffiReitsch
Жыл бұрын
@@gaylecheung3087 "Leaving oils from your finger is your hands.." ?
@toomanyaccounts
Жыл бұрын
@@JohnSmith-bw8dn they showed the difference between backyard hobbyists and professional sub builders. Triton Submarines is professional sub builders
@waynesharp1690
Жыл бұрын
Be lucky if that cabin fibre edge goes 2 inches into the titanium ring. Fancy risking your life on 2 inches of a material that wasn't up to the job.
@davidGrainger
Жыл бұрын
A couple of additions to your analysis - there is a video of them applying the adhesive to the titanium ring, which shows them using flexible spreaders similar to those used by auto body technicians. While these work well to fair auto body repairs, they are inappropriate for applying adhesive because it's impossible to get an even thickness of adhesive. The spreaders used did not appear to have serrations on the edge. Serrations, in combination with a stiffer metal blade tool, would have made it possible to achieve an even thickness of adhesive. There is also a video of them lowering the Ti ring onto the CF after the adhesive was applied to both parts . There appears to be no adhesive "squeeze-out" after the Ti ring is fully seated, making me think that there was not enough adhesive used. It looks like they put blue painter's tape around the outside bottom edge of the Ti ring to make it easier to clean off squeeze-out, but there wasn't any squeeze-out shown in the video. There does not appear to be any blue tape on the CF. Maybe they had tape on the CF when they applied the adhesive to it, then pulled the tape before lowering the Ti ring, but why would they do that?
@JoediyLab
Жыл бұрын
Yes I was thinking the same thing. The epoxy specs I showed from 3M in the video recommends a 7 mil thickness. They appeared to spread the epoxy too thick on the titanium. Thanks for the comment
@Andy-df5fj
Жыл бұрын
I recall an Oceangate video where Rush was speaking of the glue joint where he stressed they have to use enough, but not too much glue which suggests to me that they didn't rely on excess glue squeezing out, but rather preferred to use a calculated amount to avoid excess. I have no idea why.
@tarantellalarouge7632
Жыл бұрын
exactly the same tool to apply cream on a cake !
@TechWizMaster
Жыл бұрын
you know once under water they wouldn't even need to have the two pieces glued together...the pressure of the water alone will make it impossible to separate the caps even if you'd try...so the glue as NOTHING to do with all this.
@Andy-df5fj
Жыл бұрын
@@TechWizMaster While it's true that the pressure would squeeze on the caps, the glue itself is still subject to pressures and could extrude through the gap. Still, I'm more concerned about the thin titanium flange that interfaces with the inner diameters on the ends of the carbon fiber tube. Under pressure, the walls of a cylinder are the weakest point and as it compresses under pressure, that thin flange is to weak to resist collapse.
@damienharrison1
Жыл бұрын
Sounds much better thanks. Could be louder, otherwise it's a big improvement.
@JoediyLab
Жыл бұрын
Yes, will do
@creakinator
Жыл бұрын
Yes, louder.
@armandblake
Жыл бұрын
Glad to see you mentioned Pagani Automobili. I visited the factory this year and their cars are an engineering marvel. Horacio Pagani developed carbotanium to use it in the highly stressed parts of the frame, it is designed to improve carbon fiber strength under compression as well as mitigating its tendency to shatter at impact.
@JoediyLab
Жыл бұрын
Very cool, would love to see their facility and their processes. Thanks for the information.
@NoNORADon911
Жыл бұрын
@@JoediyLab Mic is good but volume is low.
@bestopinion9257
Жыл бұрын
Pagani was what this Rush guy believed about himself. He was a young employee at Lamborghini and he made its own brand because Lamborghini refused his ideas and remained more traditionalist. Now Pagani is a successful brand and Lamborghini lives thanks to Volkswagen.
@kenday7942
Жыл бұрын
I think they’re onto something there. I’ve been expressing great concern with the glue up process all along. Normally you don’t get a glue bond between two materials without some type of pressure and/or heat. And of course surface preparation is also very important. I just thought that was the most ridiculous thing I’ve seen on this thing since the very beginning. Gluing carbon fiber to a titanium ring. - Sort of like gluing an ice cube to a butter patty in the summertime.
@JoediyLab
Жыл бұрын
Thanks for the comment
@n9zmn
Жыл бұрын
I love your analogy of the ice cube and butter. I wonder, however, how critical the carbon fiber to titanium bonding is in the undersea world it was designed for. Wouldnt all that incredible hydraulic pressure be forcing the end caps IN to the carbon fibre tube? In that case, the flange relationship would be more important than the adhesive bonding. Does that make sense?
@kinte1870
Жыл бұрын
@n9zmn No it wouldn't push the end caps into the tube. The pressure on the pressure vessel is greater because it's larger .
@vertihvost7675
Жыл бұрын
Do you know what kind of battery they used? 12V lithium?
@craigsowers8456
Жыл бұрын
@@kinte1870 not exactly ... hull imploded first IMHO ... and we both know "Water" cannot be "compressed" so it shot the end caps off like Champagne Corks. And given the videos, it would appear Rush didn't bother to even add the requisite "Primer" between faying surfaced ... otherwise, there'd be some small fibers left on the Titanium flange surfaces. Again, IMHO.
@denniss3980
Жыл бұрын
The Coast Guard wants 2 years to investigate this accident, if they would just release pictures of all the pieces and photos of where each piece was found, the KZitem community would have this thing figured out in a few days
@POVwithRC
Жыл бұрын
Bureaucracy only exists to extend its own life by pretending it is the only qualified party. The USCG and Canada's TSB are prime examples of this. We could certainly do better.
@londonoverground
Жыл бұрын
@@POVwithRCbollocks
@craigsowers8456
Жыл бұрын
LOL ... that is NOT how "Root Cause and Corrective Action" boards work (and I've attended thousands) ... I would agree that just from the video evidence that there were MANY mistakes made ... but to prevent future occurrences from happening, the entire RCCA process must be followed; keep in mind their recommendations will include multinational "Governmental Oversight" to close the loophole that allowed this tragedy to occur in the first place. Cool your jets ... but DO keep making observations ... would doubt NTSB is reading all these comments ... they ain't perfect and need all the help they can get.
@martinwhite418
Жыл бұрын
The "community" can't do interviews or get court ordered paperwork.
@alihenderson5910
Жыл бұрын
@@londonovergroundNope, perfectly true. Keep taking the boosters.
@rinzler9775
Жыл бұрын
With each dive, microfractures would have been forming in the adhesion joint, combined with hard to detect delamination. Once the pressure worked through on a single path through the joint, the pressure would have ripped it apart from the inside out, followed by the compression of the implode.
@denniss3980
Жыл бұрын
Why did the end caps separate from the rings, they were bolted to each other
@JoediyLab
Жыл бұрын
That is a good question, I do not have an answer for you.
@backfromcuba
Жыл бұрын
Big shockwave, tiny bolts.
@danieldupuys2002
Жыл бұрын
Diesel gate! boom!
@JoediyLab
Жыл бұрын
Massive force at depth
@daviddun1389
Жыл бұрын
I love epoxy, it is my go to product when I am looking for a disastrous outcome
@JoediyLab
Жыл бұрын
Actually the commercial aircraft you ride in has 20 - 35 Percent of carbon fiber parts.
@MattWhatsGoinOn
Жыл бұрын
On the recovered flange (starting at 1:11), what you’re pointing out is it’s outer circumference, which is not the bonding edge.
@iamtomkills
Жыл бұрын
Correct.
@4epa1012
Жыл бұрын
Yep
@stitchem7
Жыл бұрын
On the titanium ring are found two flanges, an inner flange and an outer flange, also a flat surface that is perpendicular to both inner and outer flanges. I call this entire configuration the bonding edge of the titanium ring, as the other edge of this ring is bolted to the forward dome. The bonding surfaces are the I.D. of the outer flange, the flat perpendicular surface, and the O.D. of the inner flange. So, to be clear, I did not refer to the titanium ring as being a flange, I was pointing out the orientation and location of the flanges that are part of the overall titanium ring.
@Slav4o911
Жыл бұрын
@@stitchem7 I wouldn't use glue at all.... I'll just use titanium cylinder between the two titanium hemispheres.... either it'll be bolted or welded. I would not put any glue between me and 360 atmospheres.... even then I would test it a 100 times underwater at twice the depth. If everything is OK then I might get down.... one thing I know from life, things will always get wrong and when they get wrong 2 times overprovision might not be enough.
@stitchem7
Жыл бұрын
@@Slav4o911 Exactly my thoughts, if they would have used a titanium hull/tube, the passengers would probably still be alive. Yes, bolted with proper seals, or welded.
@ShieldWolf1
Жыл бұрын
What is also interesting is that the "implosion" had enough force to not only take the titanium ring off the carbon fiber, but also sheared the 17 bolts holding the titanium dome onto the ring; since they were found separated.
@danieldupuys2002
Жыл бұрын
Yes it was done by the enormous explosion of the compressed air inside the hull when the carbon fiber tube imploded: similar of a giant "diesel effect"whith a compression ration around 350/1, in an diesel engine, its around 20 to25/1. Note the window also is pushed in front with it's retaining ring ans bolts ( photos wrecked parts)
@arthurdent5357
Жыл бұрын
It's possible the crew unscrewed them so they could attach it to a crane.
@ermias75ermis2
Жыл бұрын
Natures forces laugh at such mere obstacles.. It only took a millisecond to destroy this toy sub.
@78a67h
Жыл бұрын
The CF / Titanium ring bond was way weaker than the bolts holding the hemispheres so the rings must have detached before sufficient force met the bolts to make them shear.
@ronparker-q9e
Жыл бұрын
Correct on the separation of the hemisphere and ring by failure of the bolts but the bolts were not sheared. Their threads were stripped. The body of the bolt played little part in holding the flange and hemi together beyond its ability to hang on to the threads. Such a powerful force needed to pop both hemi and hull from the flanges. Add to that the speed at which the forces are applied. Such an enormous amount of force applied suddenly is a 'jerk' phenomena studied by the US Navy some years ago. If you apply a steady force up to and past the, in this case, tensile stringth of your load carrying material, you get a textbook fail. But if you apply that much force suddenly, the material will often break because the jerk effect will overpower the material's ability to cohesively stretch to the required level of strain.
@johnfisher8843
Жыл бұрын
I just noticed in a photo of Stockton Rush (CEO of OceanGate) sitting in the Titan sub. What caught my eye is that one of the bracket for mounting the digital display unit looks to be screwed into the expired carbon fibber hull. If I was 6000 lbs per square inch that’s where I’d go to test the integrity of that sub. R.I.P. to all those who lost their lives.
@AORD72
Жыл бұрын
Yea, surely that is a crazy thing to do, unless that was a internal liner?. Although I think the carbon tube was a thicker than the mathematics said. To support a monitor like that you probably want at least 10mm deep bolts, I think the wall was about 127mm thick.
@andrewcheatle4691
Жыл бұрын
I read ( sorry forget where but it was a legit source I believe ) that there was a glass fibre based inner liner to protect the internal electronics & minimise condensation issues - this was possibly the base on which were mounted internal components.
@automan1223
Жыл бұрын
the more clips of this the more I cannot imagine this not being some kind of joke or psyop. I have good working knowledge of composites/epoxies/carbon fiber...anyone who does any amount of study would find this design to be a widowmaker in about a day or 2. The fact that it made it 3000+ meters is nothing short of a miracle. The design might work if several changes are made.
@JoediyLab
Жыл бұрын
Thanks for the feedback
@cragar71260
Жыл бұрын
From a retired/disabled mechanical designers view I just CANNOT understand why stockton did not see that this adhesive bond alone was TOTALLY inadequate. Carbon fiber, yes is a great material but not without the what... 8' span of the hull being supported.i would have drawn alternative drawings showing titanium rings spaced evenly apart along with horizontal titanium supports running horizontaly evenly spaced about the dia of hill that are connected mechanically
@ftffighter
Жыл бұрын
This sub's design is only good enough for one trip and that's it in my opinion. Who in their bright mind, honestly thought that this design was sound enough to be used over and over and over again? Was there even a "Life span" estimate made to Titan?
@gailmcn
Жыл бұрын
@ftffighter given Rush's multiple statements about the "virtues" of breaking rules and ignoring safety concerns, it would not have made any difference. The companies involved in production of the hull probably did warn him of the dangers.... he would have ignored them, if he even told them the truth about how deep he planned to go.
@johnarcarese172
Жыл бұрын
Disagree - the sub was designed to go to 4,000 meters. Anything greater than 2,000 was dangerous, as we have seen. If it had been designed to go 8,000 meters, a trip to Titanic would have been far safer.
@jacquelinechellis4036
Жыл бұрын
I read a study on the bonding strength of different materials with different prep. I have always found sandblasting metals is preferred and the study confirmed this with titanium. Also a serious and thorough cleaning process so no contaminating residues at all. They were using rags to wipe titanium that might have chemical residues on them and also was there any abrasive prep on the titanium. I am confident the bond was the failure point.
@JoediyLab
Жыл бұрын
Yes it appears so, but we do not know if the carbon failed first or the bonding failed first. We will have to wait for the report, Thanks for the comment.
@StagArmslower
Жыл бұрын
the CF hull's ends were machined for straightness; I wonder if the presents of dust would weaken the joint between it and the flange.
@upperleft9502
Жыл бұрын
They also weren't wearing gloves when cleaning the mating surfaces. He's even leaning his bare forearm on it. Remember kids not to Rush things. 🤠
@gailmcn
Жыл бұрын
The compression force at that depth was also acting on the two end caps, providing some resistance to separating from the hull in at least the lateral plane. It is impossible to determine if the bond was the first point of failure, until examination of the internal side of the flanges for evidence of the type of tear-away, and remaining epoxy, if any. The interior of the flange is not visible in the photograph from the wreckage. Also, no one knows the composition or properties of the epoxy used, but we do know the composition of carbon fiber, and its properties in high compression environments, and what happened with the first CF hull Rush used. So at this early stage, being confident that the failure point is the epoxy bond is a bit like hearing hoofbeats outside your window and thinking zebra, instead of horse. A slight possibility, but far more likely it's a horse.
@Slav4o911
Жыл бұрын
@@gailmcn The glued bond just looks too shady to not be a concern.... but then again.... everything in that sub except for the titan hemispheres looks shady.
@CarolReidCA
Жыл бұрын
Hi Joe, Sounds great! A tad more volume would be great. Great analysis. The sounds described in previous dives, and if that transcript that is everywhere is legitimate, would suggest microfractures from air spaces in the carbon fiber hull, which seemed to be wrapped like thread on a spool with no cross-fibers. A collapse of the carbon fiber, structural hull would seemingly be a likely cause. In the transcript, they also mentioned RTM hull monitors were "all red" shortly before the implosion, suggesting a hull failure was eminent. The bonding between the titanium rings and the carbon fiber hull was certainly a point of contention, yet there were many. FYI, The USCG has the remains of the Titan vessel in their possession and will seemingly be conducting the analysis. The lack of any pieces of the carbon fiber hull suggests that during failure, it perhaps turned into chicken downy fluff-like pieces. The plexiglass view port was also only rated to 1,300m and is also a potential primary point of failure. The winding of the carbon fiber seemed to NOT be vacuumed or autoclaved, which, if the case, would've left small air bubbles in the wrap, which under pressure were likely failing, as microfractures would have been the sounds the prior passengers and crew were describing, yet certainly not the carbon fiber "settling". That should NOT have been ignored. Despite the additional implosive stresses and heat placed on the structural parts, the titanium rings and caps were still intact. The Locktite adhesive is amazing, yet if not properly applied, such as being off-center, (thin on 1 side, thick on the other, as there was no centering of the tube with centering of the rings that I saw in OceanGate's assembly videos.) Lack of abrasive, lack of chemical bonding, and even improper mixing are also additional concerns. Hardware had also been swapped out, and there are many iterations of this submersible. If the coms are legitimate, the Titan was heavily negatively buoyant upon the beginning of the dive, as their rate of descent was already faster than was planned and accelerated past what their sensors were reading, in an uncontrolled descent. The reported coms say they were at 2960m at 9:17am, then at 9:28am were at 3433m! They had started off at 28m/minute, next depth report they were at 39.46m/minute, then at 43m/minute on their last report before ascending slightly before the implosion. Their rate was reported at 9:30am to be 35m/minute, yet they had already exceeded that rate. Their planned rate of descent was 25.33m/minute if calculated at 3,800m taking 2.5 hours to get there. They were in an uncontrolled descent, which would've caused an increase in stresses on the hull, above and beyond the atmospheric pressure, which is calculated at 1ATM (atmosphere) of air pressure at sea level (14.7psi) + 1 ATM for every 33 feet of seawater (or 10.0584m). At 2.4 miles or 3862.426 meters (12672 feet) they would've been at 384ATMs or 385ATAs (Atmospheres Absolute, as you add 1 atmosphere for air pressure.) At 14.7psi per atmosphere, at the top of the Titanic as reported at 2.4 miles, the ambient static (still with no current, no descent or other stresses) pressure would've been 5,659.5psi. Their reported deepest depth was 3,476m (11,405 feet rounded up to nearest feet) or 346.6ATAs, or just over 5,095psi of static pressure, not including other stresses on the hull. I hope you find this helpful! Please feel free to share. My hope is that young people considering a career in underwater research, engineering, etc. will learn from this accident, and will take the physics of diving very seriously. Physics doesn't care if you don't go home at the end of the day. Thank you for the explanations of the adhesives. As for the "carbon fiber", there are many types. It's been reported that the carbon fiber used was expired aircraft carbon fiber manufactured by Mitsubishi. I haven't heard what type of resin was used. Again, no autoclave or vacuum seemed to be used.😮 I didn't see any crossthreads/mesh used in the manufacturing promotional videos. It appeared as though it was wound semi-uni-directional, like thread on a spool. Prospective and new engineers PLEASE take your projects seriously! People's lives are depending on you doing an excellent job. Never be a "Yes-man"! If somethings wrong or doesn't seem right, speak up! That will limit the lawsuits as well.
@JoediyLab
Жыл бұрын
Thanks for the comment, Yes I will increase the volume.
@Wallyworld30
Жыл бұрын
Joe, have you seen "Forensic Engineering & Failure Anaylsis (sic)" channel's coverage of the Oceangate Titan? He'd done some unbelievable detective work combing through all video's that have been done on the Submersible especially it's construction. He has a strong theory that the Carbon Fiber hull failed where it connects with the Aft Titanium Ring. His theory is based on the frame construction in it's tail section that housed batteries and other components puts undo pressure on the aft section of the carbon fiber hull. He's gone through pictures of that section over time and points out 3 major design changes they made to that weight bearing metal frame over the past 3 years. Forensic Engineering & Failure Anaylsis (sic) channel has been combing though the evidence like Matlock he's even called the manufacturers of these different carbon fibers to figure out exactly which was used and how it was improperly used to create the ships Hull. If the "leaked" final text messages are genuine they support his theory as Stockton Rush last few messages were about loud noises from the Aft section of the Hull. Also he texted it took multiple attempts to drop the metal frame (only part of it actually dropped). In the leaked messages Stockton Rush is having tons of trouble with buoyancy. Even after jettisoning the metal landing gear the Titan is only able to rise 19 Meters in 5 minutes. Before this years dives Stockton Rush covered the entire hull in Rhino Liner. Rhino Liner has never been tested under extreme pressure and may have delaminated the Rhino Liner and allowed tons of water in between the Rhino Liner and Carbon Fiber. This additional weight would have killed the Titans Bouancy making it impossible to rise back to surface even if it didn't have a catastrophic implosion Again these are not my theories they are brilliant thought from the channel "Forensic Engineering& Failure Analysis" (sic). Does the bonding agent really make much of a difference with all the pressure pushing the hull together I'd imagine you could bond that thing with Vaseline and it would stay together with the water pressure keeping everything sealed. Cheers!
@DaHitch
Жыл бұрын
His videos might be interesting, but keep in mind he also explicitly states that "he doesn't believe in gravity", before going on to demonstrate how he completely misunderstands the concept of Newton's Apple. So I'd take any conclusions he draws with more than a few grains of salt. Having said that, water between the Rhino liner and carbon fibre would add as much weight as the water between the fairing and the hull. Nothing, while the sub is under water.
@JoediyLab
Жыл бұрын
Thanks for the comments. I will have to watch the channel you mentioned.
@chunkybuttz844
Жыл бұрын
I would hesitate to accept that channel’s information. I too began watching them but the man is tough to follow as he is very erratic and applies an elementary understanding.
@SoulDelSol
Жыл бұрын
Not if the cylinder buckled in and thwop pops out lid
@SoulDelSol
Жыл бұрын
That may explain why they sunk so quickly too. Rhino liner wth tho
@MrArdytube
Жыл бұрын
Ocean gate seemed very price sensitive, so that might have been an epoxy selection criteria… although better epoxy would likely not changed the outcome. Also, the CEO seemed to resist people telling him flaws in his plans… so he likely would have discounted research that conflicted with his decisions
@JoediyLab
Жыл бұрын
It appears so, it might have even clouded his judgement . Thanks for the comment
@yachtcaptain7320
Жыл бұрын
I might be wrong ... but the glue they employed looks awfully like JB Weld.
@martinwhite418
Жыл бұрын
My motto is "better living thru 3m". I use 3m products probably 300 days a year. Maybe more. But, there is no "glue" that anyone has designed that will withstand heat at 1 atmosphere, cold at Titanic depth, sea water proof, able to "glue" titanium to much of anything, able to not get pressure washed out at that depth, and be able to recover undamaged from repeated compression/decompression cycles. How rich would I be if I could invent that? And yet goofball here thought this was a great idea.
@huntandrew4409
Жыл бұрын
the titanium ring needs to be etched in hydrofloric acid and then anodized before bonding.
@martinwhite418
Жыл бұрын
No, the way to have prevented this would have been to hydrochloric acid etch Stockton Rush.
@wshyangify
Жыл бұрын
@@martinwhite418 Give that man a break, he's currently under tremendous pressure now.
@martinwhite418
Жыл бұрын
@@wshyangify Baahahahhahh.
@kevinkelly2513
Жыл бұрын
I thought the acid etch was to passivate the titanium, and prevent galvanic corrosion with the carbon.
@huntandrew4409
Жыл бұрын
@kevinkelly2513 The acid etch will remove pasivation and make the surface rough, if anodized will make a thick oxide moleculer layer,easier to bond to. This is very common with aluminum with painting And the chemical cleaning will make surface clear from oils,well until someone puts hands on it. That part of Shiney titanium
@ianbottom7396
Жыл бұрын
Interesting Joe. No way I would have got into that sub to go down 40M let alone 4KM. With a background in heavy industrial / petrochemical refrigeration I was surprised that if they built it in this way there was no through bolts holding the titanium flanges across the longitudinal length like a standard flanged component and perhaps these could have supported the CF tube by incorporating CF saddles or similar, I’m sure there’s a whole range of other issues like compression of the CF tube and you still need bonds or gaskets between, personally I’d prefer steel, stainless or titanium. If you haven’t seen it, the hydraulic press channel has done a pretty good model simulation of a carbon fibre tube with bonded steel endcaps, the failure mode seems pretty clear in that case that the CF reaches a pressure at which it completely and in an instant implodes and seperated completely from the bonded ends. Obviously, there’s variables and he doesn’t have the same materials, epoxy or can’t reach the full pressure but it’s interesting and they also attempt to demonstrate the effects of the pressure cycling. Check it out for yourself kzitem.info/news/bejne/o4d9qqt7bKt-lWU
@JoediyLab
Жыл бұрын
Bolting through carbon fiber created isolated stress points around the holes. Bonding in the aerospace industry is very common, but you have to use the correct epoxy and the correct bonding process. Thanks for the comment
@gailmcn
Жыл бұрын
@@JoediyLab I think that was a key issue here, Rush's undergrad degree was in aerospace engineering. (Masters in business). I believe he used what he "knew" from aerospace, which has basically opposite and much smaller pressure differentials, from deep sea engineering concerns.
@Roger_and_the_Goose
Жыл бұрын
I feel that another couple of important things people aren't understanding, are the effects of very cold temperatures that the Titan experienced at the depth of Titanic. In my experience, any, if not all, adhesives become brittle at extreme cold. When you combine this with 5546.98 psi (being in salt water as opposed to 5403.09 psi in fresh water), plus a 300-400 mile towing of the Titan, put further fatal damage on this extremely fragile vessel.
@JoediyLab
Жыл бұрын
yup, my mistake I did not check the correct box, Yes valid point about the cold temp.. Thanks for the comment
@johanea
Жыл бұрын
It is above freezing no matter how deep you go? What extreme freezing temperatures are you mumbling about? However, it is entertaining to see all “experts” here. Good laughs indeed.
@Roger_and_the_Goose
Жыл бұрын
@@johanea I've been using composites in the industry for fourty years, I'd put my experience up against yours any day of the week, Einstein
@johanea
Жыл бұрын
@@Roger_and_the_Goose There is no need for such. Calling water that is 2-3C extreme freezing temperatures is enough to get an idea about your experience.
@Roger_and_the_Goose
Жыл бұрын
@@johanea I get the feeling you really must be off your meds, roll over and go back to sleep mate.
@MarkShinnick
Жыл бұрын
Yes, Composite fiber has relatively little compressive strength, so is a fundamentally flawed sole material that leaked, causing dieseling within the cabin.
@JoediyLab
Жыл бұрын
Thanks for the comment, more than likely.
@MarkShinnick
Жыл бұрын
@@JoediyLab Max frustration, apparently, for all attempting to get through to this guy. There's only so much reasoning power remaining once someone sinks so much bias invested like he apparently had. Thanks for your patient style of explanation that helps people visualize the physics.
@MarkShinnick
Жыл бұрын
@@JoediyLab Some clarification: The fibers of the Unidirectional tow windings had no apparent fiber to bind them; all that existed is epoxy. Progressive splitting with water intrusion, and operational friction rubs, between the unreinforced wound carbon tows would produce the reported sounds. The tube itself could thus have essentially split.
@Wallyworld30
Жыл бұрын
Audio sounds great maybe turn up the gain just a touch. Thanks for another great video!
@Kingofcasamere
Жыл бұрын
Great video. I’ve been wondering ever since this happened, “How in the heck did they think gluing a submarine together, was going to work?!”. You’ve throughly answered that question. Good job.
@patrickradcliffe3837
Жыл бұрын
11:08 I've worked with Scotch weld it has HORRIBLE adhesion properties with metals such as aluminum and titanium. We used it as a bedding compound for damaged fastener countersinks in carbon fiber panels on F/A-18 Hornets. I'm trying to figure out why they did not have mechanical fasteners going through the flanges and carbon fiber. I understand that it is under compression while underwater. At least on the front hatch there's a fair amount of shear and tensile force on the flange when the hatch is open.
@JoediyLab
Жыл бұрын
Good question. Thanks for the feedback
@craigsowers8456
Жыл бұрын
Firstly, the idea is to NEVER put mechanical fasteners in CF structures if possible; by cutting the CF Tow, the strength of the individual Tow (where one drills thru) is diminished to the now length of that between fasteners; not the original length/strength intent by Design Engineering. But it really wouldn't have mattered as the Hull imploded first IMHO ... that 6,000 psi would have kept the dome/flange securely in-place ... until the Hull imploded and pushed them right off ... no amount of fasteners or adhesive would have helped ... "Water" does not "compress" and when it gave way, the Water had to go somewhere (out the 2 ends). Bad design and execution all the way around. Rush even stated in one video that the "Adhesive" was actually NOT for the stated purpose ... the intent was to act as a "Buffer" between the different expansion/contraction properties of Titanium and CF. And free advice on your F/A-18 cured panels you're countersinking ... put a piece of 3M approved masking tape over the area you intend to countersink and then, with a sharpened CS bit, drill. You'll never have another CS with edge "Tear Out". Works as well on "thru holes" where tear out happens on the back side. Trust me on this Bro.
@patrickradcliffe3837
Жыл бұрын
@@craigsowers8456 No, No, No these were repairs to the damaged countersinks after the removal of striped, stuck fasteners. We had a few younger Airframers that would go a little wild with a drill trying get stuck fasteners out. As far as not having mechanical fasteners we had mechanical fasteners going through structural carbon fiber panels attached to aluminum. I agree it does not help when being compressed at 6,000 psi, but it is not always at the pressure and my question still stands with regards to tensile, and shear forces applied to flange that has the door on it. When open that door acts like a lever on the adhesive joint twisting and pulling on it.
@craigsowers8456
Жыл бұрын
@@patrickradcliffe3837 Copy that ... thought you were talking "new build"; still good hip pocket info on use of tape. As the Door can only be opened on the surface (for ingress/egress of passengers), I'm sure there are forces exerted ... it's a damn heavy door ... so hinge line may take its' toll one adhesion of the flange to hull bond line ... but since Rush elected to not do ANY Ultrasonic (and X-Ray if it looked really bad on the scope), wouldn't know that answer; if you don't inspect, everything is Peachy ... until it's not.
@CharlesVanNoland
Жыл бұрын
I can only see the tube delaminating first, from all the radial pressure around the tube along with the endcaps pressing inward on it axially. It's the polar opposite type of application I ever would've expected carbon fiber composite to be used for, and the tube giving way would've allowed anything else to happen - the titanium ring(s) separating, etc...
@JoediyLab
Жыл бұрын
Thanks for the comments
@stitchem7
Жыл бұрын
(Mistake on bonding edge.) The flange you speak of is on the 'bottom' side in the photo at 1:40 and can be seen that it was partially ripped away by the implosion. The edge your cursor is pointing at is the bolted flange. You can tell the boning flange is the one that has the large radius leading to the body of the ring as in the photo of the ring hanging by the rigging before bonding. It appears that both of the 2 inch overhanging flanges of the bonding edge have been ripped away and in one of the recovery photos you can see a deformed section of the bonding edge flange still attached to the ring.
@JoediyLab
Жыл бұрын
Thanks I will double check that.
@johndraper3210
Жыл бұрын
@@JoediyLab *EXACTLY... I was going to point that out to... Not really... I have no idea what a flange is🤷♂️🤷♂️I'll see myself out*
@oldmech619
Жыл бұрын
Thanks for pointing that out.
@holdernewtshesrearin5471
Жыл бұрын
The bonding surfaces cannot be seen in the picture. The titanium sealing ring slipped over the O.D. of the CF tube and bonded with about a 1" wide related edge at the O.D. and I.D. and about a 3.5" to 4" (the 5" wall thickness minus whatever was machined away to true and rebate the surfaces) wide surface at the end face of the CF tube.
@johndraper3210
Жыл бұрын
@@this_number 👊
@cruzdeleon1888
Жыл бұрын
I actually think those bolts had a part of ring / hull disintegration as they were HAND tightened..wtf imagine 1 or 2 or 3 bolts not tightened evenly or loose...No, the bolts were not tightened to a certain spec Just "hand tightened" all 16 17 of them
@Neur0bit
Жыл бұрын
So… How did the domed end caps get separated from the flanges? They were held together by 17 bolts… If those got separated by the implosion, then the adhesive pieces never had a chance to begin with…
@luciano2166
Жыл бұрын
good question. i want to know the answer too...
@MissX905
Жыл бұрын
likely needed a 100 bolts but that would have only saved the end cap not the little viewing window. Plus what were the bolts' strength that he used? How old were they? How tight were they torqued onto the rings and other part? What glue was being used, was it ok to be used where a vessel was always in water? Was the glue new or had it been sitting around for a bit like in some overheated area, etc etc?
@luciano2166
Жыл бұрын
@@MissX905 The CEO probably didn't care about the torques and provenance of the adhesives or the quality of the screws. Probably everything came from scrap metal.
@timjackson3954
Жыл бұрын
If the adhesive was just serving as an o-ring seal, always in compression, then that's not a problem. That the shock-wave of implosion sheared it off is unsurprising but irrelevant. There are a couple of possible failure modes though. One is that the CF tube flexed enough to part the seal and the sealant was too rigid to follow it. The other is that the sealant flowed under pressure and blew through. Neither of those modes would seem likely to implode the CF tube though, and would be relatively slow. See the Hydraulic Press channel's example where his sample tube seal failed: it just quietly flooded.
@JoediyLab
Жыл бұрын
That is a good question, I do not have an answer for you .
@IDHP
Жыл бұрын
Entitled elite narcissist who got what he deserved. RIP but wow; what a clown.
@mrkeiths48
Жыл бұрын
Wow, great information on the bonding process between the carbon fiber and titanium elements. I had flashbacks of diving on my submarine and hearing the hull creak as we went below certain depths. I am not an engineer, but these were the forces that made me concerned for the bonding process. With each dive/ascend cycle there had to be a case hardening type of effect that would eventually weaken the bond. I'm sure it's a case of no balls, no blue chips. The lesson has been learned. RIP my fellow submariners.
@JoediyLab
Жыл бұрын
Thanks for the feedback
@TechWizMaster
Жыл бұрын
you know once under water they wouldn't even need to have the two pieces glued together...the pressure of the water alone will make it impossible to separate the caps even if you'd try...so the glue as NOTHING to do with all this.
@ronparker-q9e
Жыл бұрын
@@TechWizMaster It's likely that reasoning was taken as 'innovation'. It's not a bug it's a feature! Why make a big deal of holding the flange to the tube when we all know the only way that glue will fail is if there's a hole in the hull at depth. Kind of like the acoustic sensors in the hull that tell you the hull is failing. 'Everything's in the red,' is not a useful diagnostic alert. Or that it won't matter if you're on the surface and you can't open the hull without unbolting the hemisphere 'because you're already dead.' Dead by design. Squashed like a roach in a corner nobody could reach without pointy shoes. This is some of the most bizarre thought paths for an engineer. It's such a blind dependency on the numbers and the strategy that the alarm is just there to let you know you failed at a critical point. What you gonna do about it.? You're already dead.
@PHLster
Жыл бұрын
Watching the video of them gluing this up in a warehouse, it’s obvious that hair, dirt, air bubble, or moisture will contaminate the adhesive and there’s basically nothing controlling the thickness or consistency of the adhesive application.
@louiefrancuz3282
Жыл бұрын
Looking at the epoxy joint depth and sizes of the viewport/end cap bolts, it looks like oceangate was depending on the external hydrostatic pressure to hold the joints together.
@JoediyLab
Жыл бұрын
That would be very likely.
@martinwhite418
Жыл бұрын
Yes, but what pressure do you start with? Anyone who has used wood glue. Too much pressure, and you squeeze the glue out, and you have no bond. Too little pressure, and your joint looks awful. Car mechanics, valve cover gaskets, and are designed to be uniformly tightened to seal the valve cover. But you don't go diving with your car.
@johnneyland3334
12 сағат бұрын
Wow !! Learned alot today from your presentation video. The piagiano super car manufacturing carbon fiber titanium adhesive is extremely impressive. Thanks so much. What's amazing to me is that people think that cured epoxy resin is inert but epoxy is is really just an adhesive which is not a permanent coating.
@JoediyLab
12 сағат бұрын
Thanks for your comment.
@peterwiles1299
Жыл бұрын
Agree, but further when the stress is applied (in fact very high stress) there will be differential strain between the Ti and composite. Cracking of the joint will occur as a result of each dive with water ingress. Failure becomes inevitable.
@johnneyland3334
12 сағат бұрын
I think in additional to the adhesive bonding to the titanium question we should also consider that the epoxy adhesive filler they used separated from itself...meaning it's own bond strength was exceeded upon tself and hence it separated from itself internally leaving behind hardened adhesive on both sides of the Titans implosion surfaces....so what I'm saying it's very possible they never considered the actual adhesives strengths like you said when it's immersed and constantly in a humid wet ,hot environment. I don't like the fact that they did not wet laminate the 6 one inch layers to each other as one would conventionally do. It's also very scary to think of grinding down the carbon fiber stands to smooth out wrinkles which is insane because that's breaking the actual cords of carbon fiber which is the only way it has any strength. Like cutting individual cables on a suspension bridge cable assemblies right. Crazy to think of doing such a thing...but that's what they did when they grided everytime in that part. Much of the carbon fibers therefore were not continuous strands connected to each other like you would expect them to be on any structural composite structure. Amateur builders. Shame..
@JoediyLab
10 сағат бұрын
Great points Thanks for the feedback
@vintagetrikesandquads4012
Жыл бұрын
I can't imagine using adhesives when you are dealing with 6000 psi. Maybe an outer titanium tube welded to the titanium end caps, with an inner tube of carbon fiber reinforcement that's replaceable. But it sounds like carbon fiber has micro damage every time it is cycled and there is no way to determine when it will go catastrophic.
@trentstanley5475
Жыл бұрын
Stockton Cheap skated this vessel to almost no end,,it was like having a bumper car on a NASCAR race track !!! & He knew it but he just didn't care bcus he probably thought it would hold up enough to give him time to construct a better submersible.
@JoediyLab
Жыл бұрын
Thanks for the comment
@stompinmcallister1312
Жыл бұрын
Pretty familiar with a adhesive like that and it is used in aerospace applications. I used it for avionics racks many different type of throttle quadrants, And many boeing parts even f22 raptor stuff I think its a very popular aerospace adhesive.
@JoediyLab
Жыл бұрын
Thanks for the comment, Yes Epoxy adhesive is very common in the aerospace industry
@vertihvost7675
Жыл бұрын
Loctite 9394?
@craigsowers8456
Жыл бұрын
... and I'd have made sure you used a "Primer" before applying the Adhesive right? (I was on the F-22 Program as well and the Primer is clearly listed in the job cards). Evidently, Rush skipped that step ... but really wouldn't have matter ... the Hull went first IMHO and no amount of Primer or Adhesive would have saved this vessel.
@stompinmcallister1312
Жыл бұрын
@@craigsowers8456 Agree
@stompinmcallister1312
Жыл бұрын
@@vertihvost7675 No it is a two part epoxy almost like JB weld . Mixed if my memory serves was a 2-1 mixture by weight. The place I worked at got it from McMaster car
@fredbissnette3104
Жыл бұрын
I feel like original JB weld would work great for this over 5000 psi strength
@chuckmiller5763
Жыл бұрын
Yeah, the problem is still the 5600 psi at that depth, 600 PSI more than JB weld says it can hold.
@fredbissnette3104
Жыл бұрын
@@chuckmiller5763 true
@SciHeartJourney
Жыл бұрын
If you watch the video of the "fire piston" (link below), it provides a possible explanation for what might have happened to the combustible materials inside the submersible. In my opinion, it appears that the hull and everything within it vaporized. To confirm or challenge this theory, it would be helpful to examine the interface where the hull once met the titanium ring. Specifically, we should look for signs of heat scoring or shearing, as well as any indications of air bubbles where the failure occurred. In a typical diesel engine, air is compressed roughly 14 times before fuel is added, and it ignites instantly under those conditions. Now, imagine if the compression were 400 times! When the implosion occurred, it generated extremely high temperatures, potentially surpassing those found on the surface of the sun. While I calculated the temperature to be around 120,000 degrees Kelvin, I find it hard to believe that it reached such a level. Nevertheless, it must have been exceedingly hot inside the submersible. In a diesel engine with a 14:1 compression ratio, all of the fuel burns. Gasoline engines typically have compression ratios ranging from 8:1 to 12:1. Although I'm not an expert in automotive fuel combustion, as a well-informed layman, I understand that higher compression ratios result in more efficient fuel consumption. With a compression ratio of 400:1, it is highly likely that everything within the hull was incinerated within an extremely short duration of approximately 0.0038667 seconds. This calculation is based on the following: the length of the tube was 5.8 meters, and the speed of sound in water is 1500 m/s. Regarding the delta air volume (pressure constant), we can consider 400 times 300 degrees K, resulting in 120,000 degrees K. By compressing a fixed volume of air into 1/400th of its original volume (pressure of ocean constant). We can apply the Universal Gas Law (PV = nRT) in this scenario. I hope that someone will point out any mistakes or provide additional insights. I have made some assumptions to simplify the calculations, so I acknowledge that the actual situation is likely more complex than what I have presented here. I look forward to hearing your thoughts. Thank you.kzitem.info/news/bejne/pYuivZmegWqUe2U
@JoediyLab
Жыл бұрын
Great info thanks
@gailmcn
Жыл бұрын
@SciHeartJourney. I also thought as you did initially, based on a typical gas compression scenario in an implosion sequence. Then when I saw the photos of the wreckage, I was surprised that none of it showed signs of scorching or even heat deformation, so I commented on that. A couple people with some experience pointed out these factors: 1. the total volume of gas was small, and compressed by the extremes at that depth, it was extremely small. 2. the gas compression occurred in a very large volume of extremely cold water, and at that millisecond or so, in what was no longer an enclosed hull (global fracturing of the CF hull). They both said that any compression/heat/ignition phase, if it occurred, would have negligible effects in this situation. (The exchange is in the comments somewhere on the BBC News episode on video of the transfer of the wreckage at St. John's).
@cecilbrisley5185
Жыл бұрын
Ever waved your finger through a candle flame? Duration of that heat is important. It was surrounded by and instantly quenched by a huge mass and volume of sub freezing material. Similar to how a 2000 degree spark from a sparkler does nothing to you or your clothing. Difference between heat and temperature. Alot of temperature, not very much heat in contrast to the surrounding materials.
@SciHeartJourney
Жыл бұрын
@cecilbrisley5185 Thank you for so clearly demonstrating the difference between heat and temperature. 👍
@Slav4o911
Жыл бұрын
I think you're right, the temperature was so high everything inside burned in an instant, along with the people inside.... that's why no bodies and no parts of the carbon fiber cylinder can be found. The more I look at what happened, the more I think it was a suicide. If you want to kill yourself and burn to dust yourself at the same time in the fastest way possible, that's one of the ways. It looks like some ritual suicide.... but why take innocent people with him.... He knew exactly what he was building, an underwater self combusting incinerator... just looking like a submersible. He was probably hoping it would implode the first time he goes down... but the thing magically held up... that's why there was no need for any safety.... because it was a death trap. People think these things happen only in the movies.... that's why everybody was so careless. That's why nobody paid any attention to the gluing process. It wasn't build to held up.... look at all the other submersibles and how they are build, especially the pressure chamber. But this.... this was build with little glue hoping the water will held it together... nah.... it was constructed as a death trap from the very beginning.
@alessandromaffei4769
Жыл бұрын
the glue is used to keep pieces together at surface level. At a depth of 10m, the water pressure will push the dome, and the ring in between, against the cylinder with a 3000kg force. At the Titanic depth the force will reach 100000t and more. Under a similar load, the titanium ring act like a rubber seal under its own elastic deformation phase. The Titan submersible was designed to take structural advantage by the outside pressure, in keeping pieces tight together. The most likely cause of the disaster is still the inward failure of the pressure chamber, by collapsing of the carbon fiber hull.
@JoediyLab
Жыл бұрын
Thanks
@alessandromaffei4769
Жыл бұрын
10000t, not 100000t.
@gregsmith2807
Жыл бұрын
I think the portal assembly blew out at the onset of implosion but the pressure was still increasing and the end caps probably ejected from the carbon fiber as it was crumbling
@JoediyLab
Жыл бұрын
It appears so. we will know for sure after the investigation is finished. Thanks for the comment
@iuhsdihdslifuvholuidfh
4 ай бұрын
That makes the most sense, There had to be internal pressure to do that.
@hannahpumpkins4359
Жыл бұрын
Glued with workers not in clean suits, not in a clean room, not temperature controlled - I mean, I'm not even close to being an engineer (I suck at maths), and if I was in charge of this project I wouldn't have glued it in a non-controlled atmosphere.
@move4dts
Жыл бұрын
Again, well done Joe. Very clear, informative. My takeaway: Examination of the bonding materials and processes used by the hull manufacturer could yield a relatively quick determination of probable cause. Thanks
@JoediyLab
Жыл бұрын
Thanks for the feedback
@realvanman1
Жыл бұрын
Have to remember that, at the pressure at the Titanic wreck site, the titanium end caps of the Titan sub were being pressed onto the carbon fiber cylinder with around 7,800 tons of force. The joint between the end caps and the cylinder, being 5 inches wide, was subjected to around 18,000 psi compressive stress. Was this stress uniform? Or did the titanium flex some under the stress? I'm betting the latter as everything flexes under stress- ie strain. Not sure what that kind of stress does to the adhesive used... But, the end caps could not blow off first. Once under water, they wouldn't need any securement at all. The violent implosion would surely blow them off though. Incidentally, the hoop stress applied to the carbon fiber would be around 33,000 psi, and the vector sum of both stresses means the carbon fiber was subjected to a total of around 37,600 psi. The 5,500 psi outside pressure adds to this as well, again, vectorially, but to what depth in the material? We know it was zero on the inside. At least, until it wasn't... That guy was F-ing around with forces of nature and laws of physics that he clearly didn't fully understand. What you don't know CAN hurt you.
@JoediyLab
Жыл бұрын
Yes more than likely the carbon fiber failed first. thanks for the comments.
@brinnpope3050
Жыл бұрын
Very informative! Thank you for sharing your knowledge. You are an excellent teacher!
@JoediyLab
Жыл бұрын
Thanks
@yvesgomez
10 күн бұрын
This video aged well...
@JoediyLab
10 күн бұрын
Thanks 👍
@Relkond
Жыл бұрын
When the sub was crushed, you had an energy release in the neighborhood of 47lb of TNT detonating (if I’m recalling the correct numbers). That released energy would focus itself at the boundaries between materials - the titanium would have been ringing like a bell struck by the worlds largest firecracker, using that energy to free itself of all bonded material. Not a materials engineer (I do software, not hardware), but I’d expect the rings to be free of adhesives after that, even if the bonding was sound.
@gailmcn
Жыл бұрын
Also the 5 day submersion in salt water may have had an effect
@Handlebar-MustDash
Жыл бұрын
Seems to me that the bonding of the Titanium flanges to the Carbon Fibre Hull and possibly the Titanium domes to the Titanium flanges should have been positioned for the initial fit inside a vacuum to prevent air bubbles in the bonding substrate, then allowed to cure in air. In view of the fact that epoxy was used in the laying and composition of the carbon fibre, surely any engineered machine is only as strong as it's weakest component. Titanium is remarkably unreactive if I recall my Chemistry from back in College, that could be both good and bad, good from a corrosion point of view and face to face sealing but bad in that most things would not form a good reactive bond to something so unreactive. The best bonds are formed where a chemical can slightly eat its way into a substrate and form an intrinsic part of the surface area. Were I to have designed that sub and due to financial constraints, used carbon fibre, I would have wanted to stay with a mechanical solution and have 50mm Ti tie rods, 12~18 in number equally dispersed around the perimeter of oversized Titanium flanges running the length of the submersible, from front collar to back collar. The submersible could still retain its hinged front door, I would also want an outer cylinder of Titanium maybe 30mm thick to avoid any water infusion into the epoxy/carbon fibre. Many of the old Russian Nuclear Subs were constructed of Titanium, I would have sought a source in Russia for the cylinder build to keep within a budget and not compromised by using an untested at depth composite material. You can be a maverick all you like, I am all for that approach as an individual, but putting paying customers in there knowing the risks, cynically having waiver forms made compulsory for passengers, being warned of a likely cyclical failure somewhere down the road and ignoring that because you can't let your ego be deflated and because you want peoples money, allowing a Father & Son aboard on Fathers Day, the son being just 19 years of age. Well reckless, irresponsible, greedy and ruthless only begins to cover this story.
@JoediyLab
Жыл бұрын
Normally when mixing epoxy adhesive you de-gas the epoxy in a vacuum pot to remove the air bubbles. We are not sure if that was done.
@Handlebar-MustDash
Жыл бұрын
@@JoediyLab Not fully conversant with advanced epoxy adhesives, thanks for the info. Really enjoying the depth of research you put into your videos, very thought provoking and stimulating. I completely agree with your points raised about the Titanium Collars having absolutely nothing left bonded to them. That is what set my mind in the direction of the epoxy adhesive being the failure point too. No way in the World would I ever assume that an epoxy adhesive bonded to a highly engineered surface, very tight tolerances on an extremely precise ring using one of the the most unreactive metals there is such as Titanium could ever be a good idea. He might just as well have chosen PTFE. Had he sandwiched the Carbon Fibre inside an inner and outer tube of Titanium of maybe 1 inch thick or more then used a bunch of tie rods to the exterior, I firmly believe that Rush could have been a leader in his field instead of relying on heavy domes of metal just glued to the tube either end meaning even when laid up on the docks for many months at a time in winter, gravity takes its effects, temperature expansion and contraction between a reflective silver metal and a mostly black, heat absorbing hull, UV light ageing the epoxy and then, as you have pointed out several times, towing the Submersible on its bespoke barge, cresting waves then plunging then cresting, cyclical strains on the both rigid and torsional strength of the hull. Maybe if he took the extra precautions of having the Submersible stored in climate controlled warehousing, foresaken some profit to have the sub borne on a suitable ship as he had done many times before, sought out second and third opinions on his design choices. Many retired engineers in his field would have been happy to advise simply for something to do in their retirement. I wouldn't even want to have that submersible lifted into the water from a crane for fear of the longitudinal strain on the hull from the straps underneath. It's very, very sad that Stockton Rush had that character flaw that couldn't and wouldn't let him heed the advice of wiser people, leaders in their fields, those giants on whose shoulders we all must perch from an early age to learn and improve upon previous work done in any of our chosen career paths. Not much innovation has happened in this modern day space race, engineering that must also have the additional and most complex functionality of keeping humans safe in extremely hostile and alien environments. That is not likely to change drastically in any way. Deep sea diving has not changed much in 70 years. You can't cut corners with this type of science, it is inevitable that nature will bite back very hard and take your life and those you involve in the endeavour. Following Steve Jobs mantra of simplification is highly unsuitable for this line of work, crazy that he took inspiration from a guy who built phones and tried to apply that to deep sea exploration, yet he completely ignored the guys he should have listened to, the guys who have safely done this with thousands of safe descents to show a proven track record with zero fatalities. Willing to bet that even though he was based in Everett WA, the home of Fluke multimeters and testers, he got a free Home Depot meter to wire the sub. He cheapened out on the weirdest things, Logitech instead of an extra $20 for a PlayStation/XBox controller, home 3D printed thumbstick extension pieces, cheap monitors, cheap LED tape lighting, no doubt cheap battery packs with not enough power to light the voyage down or up, an acrylic/ plexiglass or similar porthole rated to ⅓ of the maximum dive depth, no seating of any kind, hard flooring with a thin piece of carpet, home rated security cameras to drive the sub, out of date carbon fibre twine, a small Bluetooth speaker to play Celine Dion on a loop. Were the O² cylinders purchased from a moonlighting ambulance driver? Were the CO² scrubbers just 2x old gasmask cannisters? These are questions you have to ask with a character like Stockton Rush I have asked myself a number of times if Rush would have brought one of his own kids onboard for that dive on that day, my conclusion is that he wouldn't ~ that time or ever. Seems to me he was feeling the financial strain of not bringing in enough revenue and that he was trying to build up a pot of money to build a new safer model, a Titan 3. He had to know deep down that he was fighting the odds every time he dived that machine, the cracking noises, the employee pointing out the delamination of the Carbon Fibre, the recurrent battery problems, the inept wiring of the port & starboard thrusters comically leaving the sub spinning all the while it was meant to go in forward or reverse direction, the customers who took one look inside the sub and said 'No way man!'. Having to sue to retain his former employees silence on the failings, he absolutely knew things were bad, you can lie to everybody with just one exception...... yourself.
@luissoto5942
Жыл бұрын
I totally agree that maybe the biggest issue was that bond and not the hull itself...maybe carbon fiber was not a bad idea...but the bond together definitely couldn't withstand that preasure.
@anthonytimpson4975
Жыл бұрын
nah the carbon fiber was a bad idea
@JoediyLab
Жыл бұрын
Yes not sure what failed first, the flange or the carbon fiber, when then blew the flange off. In the recovery video that appears to be no carbon fiber visible.
@MrNota500
Жыл бұрын
The list of what was done right is shorter than what was done wrong. Carbon fiber was definitely not the right choice. That's right from the Navy, rush said the Navy did experiments with composites and concluded they were not fit for pressure vessels. So he knew but thought he knew something the Navy didn't. I think he brought his aeronautics engineering to the Ocean Gate projects and the two are completely different environments. What works in one does not apply to the other.
@luissoto5942
Жыл бұрын
@@MrNota500 that's all good...but in order to move on and perfect something we need to see what was done wrong and how can we make it better...yea he fucked up...but it's to late for that know...got to admire what he tried to do.
@gailmcn
Жыл бұрын
@@MrNota500 Thank you! Almost nobody acknowledges the profound difference between the basic issues in aeronautics and deep sea aquanautics. You can see in.the design of the Titan the influence of Rush's aerospace training, and see it in his use of carbon fiber. In fact, he only had an undergrad degree in aerospace engineering, with only 2-3 years total of professional experience as a test pilot engineer. His Masters was in Business Admin. This was not a guy who should have been running the production of a submarine vehicle, especially for such extreme depth.
@JohnnyRebel1776
Жыл бұрын
Well if the hull failed first (more than likely) then it's really irrelevant that caps blew off. Even if they held the result would have been the same.
@DJ-ws6je
Жыл бұрын
Bro used Walmart Elmers glue to put together a middle school science project and called it a submersible.
@TirarADeguello
Жыл бұрын
New microphone is fantastic compared to past video sounds.
@JoediyLab
Жыл бұрын
Thanks
@kentharris7427
Жыл бұрын
From what I understand the Carbon Fiber at 5,600 PSI would shrink by 19 mm (3/4 inches), from going over several sources there is no mention of the shrinkage of the Titanium rings. Even with all the glue gone the end caps would be held together by the water pressure. There are carbon fiber air tanks that are commercially available that are rated to 4,500 PSI and there not recommended for saltwater diving due to the corrosion properties of saltwater to the carbon fiber.
@JoediyLab
Жыл бұрын
Thanks for the feedback
@silentpoet75
Жыл бұрын
Regardless of if the titanium bonded well with the carbon fiber I have questions about how the rings would react to the pressures involved in a different manner than the carbon fiber. I would think with enough dives and cycles of compression and decompression the rings could separate even slightly from the main carbon fiber hull. Another concern I have is that it appeared they did not torque the bolts to a specific standard measured with a torque wrench.
@JoediyLab
Жыл бұрын
Correct, I did mention this in the first video. thanks
@ovalwingnut
Жыл бұрын
VOLUME: In my case the level is down about 3/6db from what I might expect. So I'm having to crank er' up some to hear. But I couldn't say for sure at this point why that is. Just passing it along :O) Anyway, on with the show...
@JoediyLab
Жыл бұрын
Mic position is be worked on and volume will be increased.
@richardh3540
Жыл бұрын
No worries, we glued the titanium ring on AND we are going to bolt you inside the sub.
@ByronAgain
Жыл бұрын
What struck me was the environment in which the 'glue up' was done: An open warehouse/workshop, not a clean room. This could lead to contamination of the bonding surfaces. How was the bond cured? Was it cured at temperature in a vacuum chamber or at least under a vacuum? What were the properties of the polymer adhesives used? Did Ocean Gate engineers factor in the safety factors? Did they follow safe and established material handling protocols?
@JoediyLab
Жыл бұрын
All good questions
@keithcitizen4855
Жыл бұрын
It would of been something to of drilled holes in the titanium ring for the adhesive to grab onto let alone a platted arrangement through those holes. Guessing the bond was only looked at as a glorified rubber O ring
@VitruviunMan
Жыл бұрын
Boat builder here. I couldn’t believe this epoxy type adhesive application to the titanium. Anytime we laminate aluminum for strength, it is always roughed up with a grinder for better tooth. I didn’t see any of that on the flange of the titan. Also in the video they are laying up wet fiber in an overlap which is just not even close to the quality of composite you would get with pre preg carbon and vacuum bagging. Really surprised that death tube lasted several dives.
@JoediyLab
Жыл бұрын
Thanks for the feedback
@Gary-Seven-and-Isis-in-1968
Жыл бұрын
A nicely presented analysis of this problem with the adhesion. I think the lack of any remains of any carbon fibre anywhere is a real red flag. The known fact that the submersible survived previous trips to the Titanic indicates that the bond was sufficient, that the carbon fibre was sufficient for a given number of trips or service cycles. Fatigue was the craft's downfall and gradual delamination of the carbon fibre layers meant that the hull failed as shown in tests here on KZitem, as it collapsed it twisted very fast as it contracted for a very tiny amount of time, probably shearing the glue right off the end flange with such force that it almost looks polished. In short, the end caps couldn't keep up with the rest of the hull as it twisted during disintegration. The overall design was terrible, that was to blame rather the bond itself.
@JoediyLab
Жыл бұрын
Thanks for your feedback
@yoopermary
Жыл бұрын
Mic is better but even with my volume turned up to max I'm struggling to hear.
@JoediyLab
Жыл бұрын
Thanks, I am fine tuning the volumne
@mattjohnson1775
Жыл бұрын
I think narcissism was the main reason this tragedy happened.
@TheFarmanimalfriend
Жыл бұрын
Why didn't they rough up the surface of the titanium as well the carbon fiber with some fine grit sandpaper for the adhesive to soak into? They could have an acid wash to etch the titanium surface. What did they do to prepare the carbon fiber? Did they use hydraulic clamps to hold the pieces together while the adhesive set? Doing it as sloppily as they did, shows an inherent misunderstanding of the seriousness of what they were doing and the lives that would be dependent upon their doing their jobs well.
@JoediyLab
Жыл бұрын
Do not know if they roughed up the surface. Looks like than sanded the surface to rough it up,No clamps during the cure.
@gasovensforqcult
Жыл бұрын
You asked what type of epoxy adhesive Oceangate used. We can safely say most likely whatever was on discount or closeout.
@JoediyLab
Жыл бұрын
You may be right. Very scary.
@StagArmslower
Жыл бұрын
Just for start without watching your video I understand that all glued slip type fittings have to rotate to prevent channeling. When just straight push is applied you are risking creating longitudinal channels which will allow water to penetrate the joint
@JoediyLab
Жыл бұрын
Thanks for the comment
@yoshiprime3949
Жыл бұрын
I'm not a engineer, but trying to bond titanium steel to carbon fibre plastic using only glue does not sound like a great idea, much less sending it into the abyss of the ocean...
@JoediyLab
Жыл бұрын
Using epoxy adhesive is very common in the aerospace industry. But you have to use the right material and the right process. Thanks for the comment
@richardwellons5138
Жыл бұрын
At about 10:30, the pressure calculation for depth should have been for salt water, and not the default 'fresh' which was used [not that at those values, who cares ...]
@RuiLeTubo
Жыл бұрын
Exactly. Humans make mistakes😔
@JoediyLab
Жыл бұрын
Thanks, yes I forgot to check that box,. I normally check it.
@Robrob007
Жыл бұрын
This would have been useful a few weeks ago
@fnersch3367
Жыл бұрын
I bet the epoxy on the end ring debonded from the carbon fiber cylinder. The cylinder flexed to cause this to happen.
@JoediyLab
Жыл бұрын
Thanks
@johngabucci
Жыл бұрын
The content is great. The audio quality not so great. It’s hard to hear you even at max volume on my iphone. 📲
@JoediyLab
Жыл бұрын
Thanks I am working on better mic position and volume levels
@onguardmedia6107
Жыл бұрын
He probably got the epoxy from a hardware store.
@earth_ling
Жыл бұрын
I know that carbon fibre was chosen because of cost. But if I were going to build a deep diving vessel it would be made of spun steel, Titanium or machined aluminum. Due to the extreme pressure at that depth, the design would be a sphere. It would be a solid sphere shape with no bolted seams. At that depth, a window would be useless. Video cameras would make up the visual aspect of it. I would have redundancy after redundancy built in for safety. With a dedicated way to return to the surface. Definitely a control system that didn’t involve a Gameboy controller. There would definitely be a hatch in the event it were to get away from the surface ship to allow egress from the hull.
@JoediyLab
Жыл бұрын
Good points, thanks
@janezjonsa3165
Жыл бұрын
Oh god man, learn to speak into microphone
@steveo601
14 сағат бұрын
An Elmer’s glue/peanut butter mix should never be used for deep sea exploration!!!!!
@thomasschleis2545
Жыл бұрын
Say, I'm going to take a plastic tube I got for cheap because it was a second, use JB weld to epoxy on some metal ends, and take it deep sea diving. What do you think? This was not far off.
@lisaschuster686
Жыл бұрын
How much are you charging per ticket? 😮
@thomasschleis2545
Жыл бұрын
Free, I'll drive.
@denlsgoulden2307
Жыл бұрын
Seems it was a huge mistake constructing this hull assembly from two completely different material types. Carbon fibre os a relatively new material which dosent have the necessary "track record" in this type of application, and is allegedly difficult to successfully NDT. Surely would have been better to have constructed a metallic spherical based structure of one material type.
@danieldupuys2002
Жыл бұрын
Not whith the same design and dimensions, impossible to float on surface probably, this is the main reason of that choice, light weight and 5 passengers.
@Darryl_Frost
Жыл бұрын
Thankyou, very interesting and the audio is perfect..
@JoediyLab
Жыл бұрын
Thanks
@kaioser
Жыл бұрын
Gluing pieces of sandpaper together what could go wrong?
@JoediyLab
Жыл бұрын
Thanks for the comment
@PoorMansChemist
Жыл бұрын
0:18 WAY WAY better audio quality!! Thank you!!! 👍🙂👍
@JoediyLab
Жыл бұрын
Thanks
@PoorMansChemist
Жыл бұрын
@@JoediyLab Anytime! Great video as always. I found the mention of van der Waals forces as the bonding force for some of these adhesives a bit odd. vdW forces arent noted for their strength. If it were me Id rather trust my life to some sigma and pi covalent bonds between the adhesive and the substrate. Surely there is something that will react with titanium that can also he made to bond to some other polymer matrix.
@JustinWyllie
Жыл бұрын
The volume recording level is too low.
@defendermodsandtravels
Жыл бұрын
There's a fundamental and very basic error in this video. The presenter is confusing the external hydrostatc pressure with the interface stress which the adhesive will need to transmit,. These are totally different. There are 3 primary stresses and one parasitic stress. 1. The axial compressive stress caused by the hydrostatic preesure on the end cap. 2. A radial shear stress caused by the differential thermal contraction of the two materials (difference in temperature between the workshop and the seafloor). 3. A radial shear stress caused by the differential contraction of the two components under the hydrostatic pressure (different elastic moduli). 4. A self-equilibrating stress system caused by the the geometric mismatch between the two components. A simple axisymmetric FE analysis will quickly give a good estimate of these. The presenter appears to be a Materials Engineer with little knowledge of structural mechanics. My background is PhD level Strucural Engineer who researched the fracture of sumarine hulls sponsred by the US Navy.
@JoediyLab
Жыл бұрын
Yes, you are correct. I was corrected and yes in the first video I stated that I am not a mechanical engineer, and any feedback would be welcomed and I am open to corrections of my errors. Thanks
@defendermodsandtravels
Жыл бұрын
@@JoediyLabThanks. I have no problems with honest errors when the person acknowledges his limitations (and I know where mine are). That is how we all learn. When I get home from my travels (currently in Portugal) I'll do a qick FE analysis of the hull to find out the approximate joint stresses which I will be happy to share. It won't be perfect because the CF composite is very anisotropic. Please also be aware that there's no way the Ti rings could have been "blown off" under such external pressure This was a shear failure at the joint.
@JoediyLab
Жыл бұрын
Thanks so much for the information. What is your opinion then of why all of the bolts on end cap and the window retaining ring blew off. I have been thinking about this as well. Again I love collaborative interaction. Thanks so much, I would be interested in your FEA.
@defendermodsandtravels
Жыл бұрын
@@JoediyLab Are you a qualified Materials Engineer? Maybe a member of ASTM?
@tcook6759
Жыл бұрын
Great video. Sound was good but I did have to turn up the volume a wee bit.
@JoediyLab
Жыл бұрын
Yes working on mic position and volume level, thanks
@notsogreat123
Жыл бұрын
We can hardly hear you ?!??!?!?!?!
@MichielvanderMeulen
Жыл бұрын
The geometry of the glueing area, and the difference in expansion between the materials is equally important as the bond quality. Loads can skyrocket with such huge glue diameters.
@JoediyLab
Жыл бұрын
Yes thanks
@fiending
Жыл бұрын
the end caps blew off like the cork on a champagne bottle 🍾
@JoediyLab
Жыл бұрын
It appears so, thanks
@jamesmcmasters9392
Жыл бұрын
Wacky idea to use glue metal carbon fiber
@JoediyLab
Жыл бұрын
Actually it is common practice to use epoxy adhesive in the aerospace industry. You cannot bolt carbon fiber together. But yes there many issues
@mercerconsulting9728
Жыл бұрын
Good post, and it answered many questions I had about carbon fiber vs. titanium, esp. the bonding aspect. BTW, your sound was a bit low; I had to turn up the volume.
@JoediyLab
Жыл бұрын
Thanks will address the volume in the next video.
@TSIXGaming
Жыл бұрын
you dont need a phd to know gluing the ends of sub together is r3trded!
@TSIXGaming
Жыл бұрын
cool video i thin the epoxy failed and fine jet of water in causing the sub to lost boyancy until more epoxy and fiber failed
@JoediyLab
Жыл бұрын
Thanks
@Thor_Asgard_
Жыл бұрын
If the damn Tube was made out of Titanium, they would now be sitting at home and enjoying their time.
@wshyangify
Жыл бұрын
But the vessel wouldn't have been viable. The only reason why they had a sub in the first place is because it's light enough for the puny batteries on board to float it back up.
@JoediyLab
Жыл бұрын
That is true, but with proper design and manufacture he could have made it work. He did other dives to that depth.
@stanley917
Жыл бұрын
Since the pressure is applied to the outside of the 'capsule', aren't the forces present pressing the end caps onto the composite tube as well as compressing the tube?
@backfromcuba
Жыл бұрын
They are. The problem is that the two materials don't compress equally.
@JoediyLab
Жыл бұрын
Correct, as we discussed in the first video carbon fiber and titanium compress and expand at different rates.
@stanley917
Жыл бұрын
@@JoediyLab not the point. The end cap is captured on the end of the tube by the flange on the titanium cap, the deeper it goes, the more force pressing the two surfaces together. The external pressure would keep it in place without bonding material (assuming perfect mating surfaces no leakage - bonding material in a sense compensating for surface imperfections, acting as a gasket) Latest released communications indicate they knew they were in trouble, the real-time monitoring system (RMS) warnings were active, they jettisoned ballast and the landing gear in an attempt to surface before the breech and collapse. Of course, it is the internet, all information is always suspect.
@maxbrazil3712
Жыл бұрын
Epoxy glue applied unevenly using a spackling spreader in a non-sterile environment? Yeah, what could go wrong?
@JoediyLab
Жыл бұрын
Yes, did you also notice the guy wiping down the titanium with no gloves on. Thanks for the comment
@holdernewtshesrearin5471
Жыл бұрын
What most are overlooking is the bond between the carbon fiber tube hull and the titanium sealing ring is not necessarily under any great structural load as Titan is designed. The water pressure at the depths it's designed for will essentially force together the end caps and hull without any adhesion or mechanical attachment at all. Much like how a car door of a sunken car won't open as long as the cabin is full of air anyway. But where I think Titans designers and manufacturers failed is in the SEAL that must be present between the two critical components. If water ever found its way beyond that narrow approximate 1" wide bonding/sealing surface at the O.D. of the CF hull and made it to the end face surface, hydraulic forces would work to seperate the two components and likely cause a failure at the corner of the CF tube face where the material is thinnest and weakest. Once that occurs I think a catastrophic failure could result. The expansion/contraction disparity between the CF and titanium and adhesive for that matter could have easily formed microscopic fissures or cracks that water at 6,000 psi could easily enter and burrow deeper through. If that "jet" or channel of water is large enough it could have easily destroyed the seal or the actual structure of the CF at its longitudinal Axis of its filaments leading to disaster. As it stands though, and taking the text message transcripts into account it would seem something had reduced the vessels buoncy from the start of the dive as evidenced by its above nominal rapid descent. The fact that the thrusters were unable to slow or arrest the descent and the RTM alarm sounding suggests possible hull deformation to the point that buoncy was reduced . I'm no oceanographic engineer so I have no idea if that's possible but being that the crew compartment was the only air filled vessel that created buoncy for the Titan it would seem something along these lines had to occur. Once ballast and then the landing frame was dumped the hull suddenly relieved of considerable weight, could have flexed and deformed enough to cause the water intrusion described above and eventual implosion. RIP
@JoediyLab
Жыл бұрын
Good points, thanks for the comment
@imho7250
Жыл бұрын
Yes, you’re right. Even the bolts holding in the porthole window and the titanium hemisphere onto the titanium ring are doing absolutely nothing at 4000 meters depth compared to the 17 million pounds of force holding the dome on. In some of the pictures of the debris it seems that the inner lip of the flange where the carbon fiber tube was bonded got mangled. But nobody will know the chain of events until all the pieces are recovered. Im also wondering what type of adhesive was used because what seems most important at that joint is the ability to allow expansion and contraction of the two dissimilar materials at different temperatures and pressures, not bond so hard that it applies stress to the carbon fiber. This sort of ties in with the CEO saying “not too thick and not too thin”. Also so far I haven’t seen any details about the aft hemisphere, either during construction or in the debris. What sort of stuffing boxes did it use to allow passage of wires and tubing to pass through? What’s behind the aft bulkhead between the passenger compartment and the aft dome? The alleged transcript makes it seem like there was some sort of problem going on for at least 15 minutes before it imploded. And I say imploded because thats the only thing that would have blown the porthole out and the front dome off the front titanium ring. If you think the static pressure of 6000 psi is high, what do you think the water hammer pressure got to as it allowed tons of nearby water to accelerate into a dead end?
@holdernewtshesrearin5471
Жыл бұрын
@@imho7250 - yeah there's much to learn about that adhesive and the geometry of the joint itself fascinates me. I think the disparity of the 3 materials, titanium, CF and the adhesive is why they designed the bonding surfaces the way they did with only a narrow approximate 1" band at the O.D. and I.D. of the CF tube hull and the majority along the 3.5" to 4" end face (5" wall thickness minus whatever was machined away to true it up and rebate the edge). That limited the movement between the materials by limiting the surface area of the bonding surface in the plane that would see the most movement. Yeah I would imagine whether the hull failed catastrophically or a much less severe failure at the bonding joint of the aft end cap/bulkhead, the massive pressure and "water hammer" would have totally destroyed the CF hull and the porthole and disassembled every component in an instant. As far as recovered components, we don't know if we're seeing the parts as they were discovered or perhaps after some level of disassembly once on deck of the recovery vessel for any number of reasons. It's just not possible to say until someone briefs us. All I know is OceanGate and Rush specifically was operating in such a reckless manner it was just a matter of time before something bad happened imo. It's a shame. There's a difference between pushing the envelope and being a cowboy.
@imho7250
Жыл бұрын
@@holdernewtshesrearin5471 , yes, he definitely pushed the envelope but you see people trying to “hack” the system everywhere they can. The porthole, reportedly only “certified” to 1300 meters, but most likely thats “ok, testing shows it will fail at 5200 meters, so we can give it a crush depth of 4000, a test depth of 3000 and certify it beyond any possible edge case of failure down to 1300 meters. So the CEO probably just went with the mathematical safe depth and got it for 10% of the cost. It did in fact make it down and back a few times, which means that at least initially, it was sound, but we don’t know which edge case got them in the end. One of my hobbies is electric bikes, and a popular “hack” is to get a motor controller rated at 30a for example, limited by software as it measures current across the shunt wires, and they will do a “shunt mod” where they add solder along the shunt to decrease resistance and “fool” the controller into allowing 45a when it thinks its just 30a. My stand on that is, as an enthusiast who had a pile of old controllers, and time to walk home, go for it, but for the average person they are eating into the safety margin that a Chinese manufacturer built in, for certain edge cases. If it was reliable at 45a, the Chinese would rate it at 45a and sell it for $10 more. Lol. For the titan, after building it, I would need to see it raised and lowered with no life onboard to at least 6000 meters once and 5000 meters 10 times , then do ultrasonic inspection before allowing it to carry passengers down to 4000 meters. And this is probably much less stringent than any certification agency would use. We will see something similar on the first humans going to Mars. They will all also sign waivers. Lol
@staple765
Жыл бұрын
Sounds much better Joe thanks. I’m enjoying your analysis and videos 😊
@JoediyLab
Жыл бұрын
Thanks
@travisporco
Жыл бұрын
How would these adequate adhesives do under repeated cycling?
@JoediyLab
Жыл бұрын
More than likely that would have weakened as well. Repeated stress and strain will do that. Thanks
@JoediyLab
Жыл бұрын
Any material is going to weaken over time. All components have a cycle life and must be replaced.
@vwdarrin
Жыл бұрын
We use titanium rods in our race motors. If they get any kind of scratches they are taking out of service. If you get any kind of scratching on the titanium surface it is compromised therefore making it impossible to get any kind of a structural bond.
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