Faceplate Turning?

[ACHiPo]

I wanted to clean up a 1/2" x 8" copper disk for a display. I mounted the disk onto my lathe's faceplate. Unfortunately the saddle won't go far enough left for me to true up the edge or face the disk. What's the best way to machine it. While I'm asking, what would be a good cutting tool--from what I've read a sharp HSS tool with a rounded nose works best on copper (I know I've got a carbide tool in there--it was left over from a previous project)?

 

[kvt]

you could do like I have done. Turn the QCTP counter clockwise 90 degrees, then put the opposite tool in but you may have to leave it hanging out just a little more so that it will catch all of your disk. Another opption is to shift your tools post about 45 degrees and use a diff tool or grind one that will give you a good finish on it. Those are things I have done in the past.

 

[kd4gij]

Turn your compound to 90deg to the head stock and advance it fare enough to turn it.

 

[ACHiPo]

Turn your compound to 90deg to the head stock and advance it fare enough to turn it.

That's what I was leaning toward doing. I either need to buy some skinny wrenches or grind an open-end wrench so it will fit in the slot of my compound.

Thanks!

 

[kd4gij]

I have also used a left hand boring bar to turn and face over sized parts

 

[Wreck™Wreck]

Rotate the tool post 180 degrees and place a left handed tool on the outside.
If you do not have the correct tool place a right handed boring bar on the outside held upsidedown and run the spindle in reverse.

I turn OD tapers from the compound with a boring bar on the back of the part and the the spindle in reverse, this is much more user friendly.

 

[ACHiPo]

I was able to machine the edge and face, but there was a lot of pull out (for lack of a better term). Thinking I'll just finish with emery cloth or sand paper--I'm definitely not up to the challenge of getting a good finish on this stuff--it's like machining taffy!

Thanks everyone!

 

[pdentrem]

Yeah, cutting copper is tough! It is stringy and grabby. It also depends on the purity of the metal. Silver is another that acts the same way. We use TrimSol at a 1:10 mix Trim to water and Diamond tipped tooling, high rpm and fine feeds.
Pierre

 

[ACHiPo]

I’m all out of diamond tipped tooling
I suspect I can do better than I did with proper sharpening of HSS bits, but I don’t think I can get the finish I want. Abrasives to the rescue!