Optimizing the Trigger Piston Design
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Optimizing the design.... or more appropriately, optimizing the manufacturing process in design. In the picture, the above is a one-piece clone "piston" of the 2 stage trigger of an F-16. It's lathed on a mini-lathe, out of an OD=8mm brass. First, it has to be turned down to OD=7.5mm, then, the middle section has to be turned down to 4.5mm, then one end has to be drilled with an D=1/8" hole. This whole thing has approximately the same dimensions as the real one. The blunt nose section's precise shape is not important. The original is a circular dome (plastic injection molded part). But, mine is... well, filed on a lathe. The curve? I have no idea... well, about there. But... if you ain't got a lathe.... that is going to be very difficult to make. Just drilling a D=1/8" on an D=4mm hole is going to make you sweat. Any deviation on the center finding (or even wandering of the drill bit) will make it very obvious on these small diameter, thin walled part....