thanks again Roy.
Resolution to 0.0001mm, one ten millionth of a meter is currently beyond my ability – but not by much! One could theoretically approach 1 micron resolution (1/1,000,000m), and cheaply to boot. I say theoretical because things like the rigidity of the machine, linear bearing clearance, etc seriously come into play when you’re talking 1/100,000 of an inch!
How to accomplish this bodacious claim? I think it would be possible with fine tpi lead screw, geared down servers, and a closed loop system with Newall linear encoders. These have 1 micron resolution and can be used submerged and supposedly are tolerant to magnetic forces (is there much emf or other interference generated by edm?). Heck, fine ready rod with a plastic nut and simple anti-backlash would do – the positional accuracy is from the encoders. This idea would have to be linear – rotary encoders or steppers wouldn’t work, at least not with ready rod
http://www.newall.com/LEDs/leds.htm
basing the system on the prepackaged accuracy of the Newalls and using really inexpensive components to drive the motion is a unique opportunity presented by the EDM characteristic that 1) motion slow and 2) involves no cutting force.
Now I don’t really think I’m going to be cutting to 1/100,000”, but that there is a strategy to get this kind of resolution and its only 10x of what is state of the art, gives me encouragement that a high class machine could be built (or at least as far as the first 1/3 goes!)
The VMS is a great project – bunch of guys putting a lot of work into something for the betterment of all. I’m sure Ron would welcome another contributing editor
…or maybe we’ll just collect all your posts and send em to him
Mike