Grinding glass rods.

[dkemppai]

What is it you are building??

The hobby project is a precision pendulum. Looking for different materials for the rod.

Fused Quartz is common, but has higher tempco. Invar36, also common but exhibits long term drift. Actually got my hands on some monocrystaline silicon, which also needs to be ground to shape.
Higher tempco, but supposedly no thermal hysteresis.

This stuff was the ultimate target material. Never figured I'd actually get my hands on any this length.

Mostly material collecting phase right now. But getting to start to think more seriously about grinding this stuff to size.

 

[dkemppai]

Material is in hand now.

Looking it over. It appears to core drilled from a 40" thick slab. A little bit of overlap is apparent on the blanks. They may have used a 20" core drill, and drilled to 20" then switched to a 40" for the last half. One end exhibits a bit of chipout, probably from when the core broke free.

But, WOW. Never, in a million years, figured any would be available in this length.

Still pondering the 'correct' machine to grind this on. I think it will be purpose built. (And maybe even CNC, to grind tapers, or odd features, like the threads, etc.