Modifying small screws

[PJs]

It's eye candy and a real attention getter as a desk ornament.

That's an understatement but, either working or eyecandy...its stunning and thought provoking too!

Thanks for the clarity on the trigger/firing mechanism. Thanks also for the links and I won't miss either of those on that trip! The menu looks Outstanding! How could I not trust Einstein with his tongue out¿ ~PJ

[rlm98253]

That, sir, is a work of art.

[olderdan]

I stopped model engineering some years ago but never achieved anything as impressive as that, just studying the photo's makes you realize the many and varied setups and types of machining involved. Beautiful work.

[mklotz]

I stopped model engineering some years ago but never achieved anything as impressive as that, just studying the photo's makes you realize the many and varied setups and types of machining involved. Beautiful work.

Thanks, Dan.

Some of the more interesting bits are completely hidden. The conical gun base is one-half of a DIY ball bearing. Half cylindrical tracks in the conical section and the flat plate section on which it rests form the races that enclose ~40 1/8" steel balls that form the bearing. Like the gearing, these are lubricated with high-viscosity grease (the kind used in microscope and telescope focusing gear) to give that slow, smooth feel one associates with big machinery.

Inside the conical base is a bevel gear, fixed teeth-up to the base plate. A companion bevel gear engages it and has a shaft that projects horizontally through the conical base to an exterior spur gear. This spur gear is driven by the worm on the end of the shaft that connects to the hand wheel for the trainer.

One of the toughest jobs was arranging for the interrupted thread breech block to close smoothly. Lots of cut and try work there. I was often tempted to build a simpler sliding breech as seen on many guns but the interrupted thread just looks so cool I had to persist.

[Ralphxyz]

Wow!!

Ralph