Step 3 in making a One Piece Cone for a model Live Steam Injector.
I made over 50 variants of this design to explore the different characteristics of overflow hole patterns. Usually the Condensing, Mixing and Delivery Cones are separate pieces. However, this development proved that you can make all three cones as one piece, with a taper from both ends and drilled holes instead of the gaps. This is much easier to make, but nobody had previously been able to make it work.
I designed a simple 4th axis which is a converted tilting rotary table. A toothed belt provides the reduction from an AC Servo.
Here it's being used to peck drill 0.4mm diameter holes with a Carbide PCB drill through to the tapered hole in the centre. Taking this gently, there's no need to centre drill. The holes are drilled in such a way that there are always between existing holes. eg the drill sequence is 0, 180, 90, 270. 45, 135, 225 degrees etc. This is so that when the drilled holes break into each other, they do so when there is equal supporting material (or not) on either side. This stops the drill from wandering.
This design works as well as any conventional injector, and I'd suggest that it's much easier to make. An article in 'The Model Engineer' explains the details of this design and the thinking behind it.
Негізгі бет Peck drilling Live Steam Injector Cone holes
Пікірлер: 2