Non-conducting tailstock material??

Date 01-03-2006 20:07

Hello: We have to replace our tailstock fixtures frequently due to arc wander and flash. We GTAW 1/4" diameter rods in automatic lathes. The weld pool is about 1/4" from the tailstock. Is there a material that is non-cunductive and relatively tough that we can machine? The tailstock is pneumatically driven so it can not be brittle. It could be a coating or plating. I thought about ceramics but I do not know enough about them. Any ideas?? We're using about 40 amps, DCEN. Fixture temperature would not exceed 300° F

By billvanderhoof (****)

Date 01-04-2006 07:06

It might be easier to isolate the whole tailstock. Mill away a bit of the bottom where it meets the bed and insert insulating material between the bed and the tailstock. Other insulators would have to be fabricated for the clamp that holds the tailstock down. One advantage would be that the area is much larger so that a weaker material can support the force.
Bill

By captaintom62 (*)

Date 01-04-2006 15:31

Great idea that I can use on a different application to address a different failure mode. In this case, once the part is positioned between the tailstock and the headstock the electrical path, if the tailstock is isolated as you suggest, would be through the part into the headstock and the tailstock would still be zapped.

By RonG

Date 01-04-2006 17:11

Not sure I under stood that but! You might consider Micarta. It is very good in such applications.

If the Tailstock is isolated, how does it get zapped? wouldn't the Head stock be the next victim?

Have you tried a ground strap ( Flat woven Copper) that rides on the work?

We do extensive welding on rotating parts and have a several different ways of grounding.

By captaintom62 (*)

Date 01-04-2006 15:57

Stupid me placed this thread in the wrong location. Sorry, I will copy it to the "Shop Talk" category.