Brazing carbide

Evening , I'm a bit confused with information overload . I'm planing to make some carbide tooling for the old Fortis , what brazing wire and flux do I need to braze onto hss ?

Thanks

Sean

Silver solder onto mild steel shank. Make sure everything is clean and fits reasonably well.

Sean,

As Dwayne says, you can use a mild steel shank. I just silver (hard) soldered the carbide to a piece of mild steel. I used uncoated carbide and used a diamond hone on the surface to be soldered before fluxing.

Thor

You can get silver solder foil which is designed especially for this task, it lets yavoid having to poke the tip with solder wire and avoid the risk of dislodging it.

Neil

We used to braze with sifbronze rods using oxy acetylene. It worked but we seemed to do it a lot? I was only 16 at the time

Bri

The ideal material for applying carbide blanks is called Tri Clad. It is a foil consisting of two layers of silver solder with copper in between. The theory is the copper can yield so the different rated of expansion of steel vs carbide will not cause cracking. I have a little left from a project many years ago. I checked the price recently and almost fell off my stool. For the size of carbides the hobbyist is likely to use, any silver solder will suffice.

Any decent silver alloy and flux will do the job. I've just done some scraping tools, and have a few more to do. Use a diamond something to really clean the carbide where you want the alloy and make sure the fit is decent with the steel. Flux the heck out of it. When heating keep the flame off the flux and the joint. Heat both pieces pretty evenly until the alloy flows. Did I mention that pre-placing the alloy in the flux at the joint is highly desireable???

I've done lots of this over the decades and it's never failed for me. The tri-foil is only really necessary when brazing a big flat area like a big carbide on a big shank.

Hey, worst is you mess it up. Then melt it off, clean it up, and try again!!

Pete

I have read of an alternative to Tri Clad in an old book, 3 bits of shim, a sandwich of brass, with a piece of copper in between. Another suggestion from the same place was to use the brass from the base of an old light bulb.

The last one I did, I used just plain brass to braze in a piece of TC salvaged from a circular saw blade to make a boring bar, it's not pretty but it works. Ian S C

Cutting edges are where You find them. Use it up, wear it out......................