machine neoprene rubber

Greetings Karl, Your rubber is indeed machineable. You can freeze it but I don't think you will need to. From the part number given I see it has a .875 hole through. Put the stuff on a mandrel that fits closely. Use the HSS cutter you describe above. When you turn it the finish will be rough. You will probably find that taking only one pass works best. Leave it a little on the plus side and use coarse sandpaper to improve the finish and achieve the exact size needed. A few months ago I machined a bunch of washers made from 70 shore A neoprene sheet. I used a trepanning tool in a boring head to cut the IDs to size. Then used the same tool to cut the ODs a little oversize. The parts were then pushed onto a mandrel that was the same size as the part the washer was going to be used on. With twenty 1/4 inch thick parts stacked on the mandrel I turned them about .010 over and sanded to finish. It worked very well. Use a vacuum cleaner to suck up the dust. Eric

--What's the application? Why not cut with scissors and jam into place?

"Karl Townsend" wrote in message news:ahZif.2422$ snipped-for-privacy@newsread1.news.pas.earthlink.net...

Lots! Sharp HSS is the key and fast speed. During the racing years, Toyo tire would shave new tires down to 1/8" tread. They had tooling that looked like a lemon zester. I made similar tools for carving pumpkins by drilling a hole at an angle near the edge of a square piece of tool steel then grinding and honing the steel around the hole until it was thin and sharp and then just "draw" on the pumpkin removing a continuous strip of peel. I have mounted box-knife blades in a holder on the lathe for washer cut-offs. I never did try coolant or dry ice...never needed it.

Dry ice works good, as does a CO2 tank with a hose. I have a couple on hand for MIG welding..so can spray CO2 directly on the rubber.

But sounds like you have the tooling right.

Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.

Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner

Much easier to grind it than to cut it. A tool post grinder or something similar driving a sanding drum(fast) will make short work of it. Make sure the lathe spindle and drum are running in the appropriate directions. Switch to a fine abrasive and you can take off a thou at a time if necessary. Mount a vacuum hose under the drum to catch the dust.

Randy

"Karl Townsend" wrote in message news:ahZif.2422$ snipped-for-privacy@newsread1.news.pas.earthlink.net...

I thought that tool was for drilling holes in your head? Karl

Yeah. I've seen that term used before too. I've also seen the word"trephinning" used to describe the same thing. ERS