Cutting and brazing Carbide

[divenpuke]

Hello,
I'm interested in making a custom 'back spot facing' tool. I've scoured the net and specialty tool stores and have been unable to find what i need so I've decided to make one.

I'd like to graft a piece of 7/16 carbide rod 1/4" long to a piece of 1/4" dia carbide rod 2" long. I couldn't find anybody that had ever brazed carbide to carbide, but I've recently tried with success! However...the 7/16 piece was 2" long when brazed. Now...how the @#$^ do I cut it? An abrasive blade in a chop saw didn't seem happy. It would probably take an entire blade to get through it. I tried hitting it w/ a chisel after scoring it w/ the chop saw and it broke on a diagonal. Suggestions?

[hoghead]

I’m a long ways away from being an expert in this area but we do make our own carbide hand scraping tools at our shop. The only thing we have found that will cut carbide is a diamond impregnated wheel. We use a flat faced grinding wheel. It looks like a steel grinding wheel but it has diamond dust bonded to the surface. I don’t have one but I’m pretty sure you can buy a diamond cut off wheel, fill up your wallet before you go shopping! As far as brazing carbide goes we have done it but we have had much better success silver soldering instead of brazing. You should be able to Google silver soldering, if you can braze you can silver solder and it will be much cleaner and stronger. I hope this helps, maybe someone with more knowledge then I will chime in here.

[MadMax]

I just had to cut a couple carbide boring bars. I had good results with a diamond coated cutting wheel. Sorry, I can't recall the brand, but it was a 4" steel wheel with about 1mm of diamond coating at the periphery and it went thru the carbide pretty well with decent control and little heating. I picked the 4" wheel because I could put it on my pedestal grinder (with a lathe turned adaptor) and it would have the right surface speed spinning at 3600rpm. 3500sfm was the upper limit speed recommended by the wheel maker which is a bit slower thn 4" @3600rpm, but 3600rpm is the no load rpm of my grinder so I figured it'd be ok.

Set up some dust suction and wear a respirator. Long term exposure to carbide grinding dust is carcinogenic, but I think infrequent exposure shouldn't be too bad.

[Superman]

Carbide indexables

a little more expensive retractables

and a flop-out retractable

plus a few other types

These may open up other ideas

[neilw20]

Superman!
Super links.
Great stuff from Airport West. Have I met you. Probably.
Neil (friend of HVH earl st)

[Mcgyver]

Sounds like you've figured out the brazing part ....carbide silver solders easily (silver soldering is brazing, i've never tried it with bonze rod)....and doesn't care whether its mate is steel or another piece of carbide . The trick is to sand of the oxide first which can be done with emery cloth (i know emery won't touch the carbide, but it will the oxide.

Carbide’s cut with abrasives, diamonds mostly. Whenever you’re cutting carbides wear a respirator. The particulates are bad, lots of cobalt in the binders and you don’t want cobalt in your body

[neilw20]

I knew someone who had been grinding carbides for years, and was with him in his final days in hospital. Died due to lack of breath!. Too young < 50 years old. Bad stuff it is.

[Aleseg]

Hi
Have you tried wire EDM machining for cutting carbide? I think is the best way to cut this kind of material.
Bye

[divenpuke]

Thanx.
Superman->Guess I didn't scour well enough! great links.