Live Wire 

As an FYI, brazing, properly done, is more than strong enough for a disc mount. It's done all the time. Probably a good idea to not put a mount on a fork that wasnt intended to have one though.
Also, stainless steel and bronze will make for a weak joint. Silver is what you needed for that, but since it is in a low-stress area you might be ok for the long run.

roynyc

Thanks for the info! That's good to know about brazing. When researching I had quite a tough time finding reliable resources to definitively tell me what joining method is good for what application. From the sites that I saw (sounds not reliable based on what you're saying), the needed method was to take a raised eyelet where the disc brake would screw into and then lay a bead over the edge of the eyelet to the fork. Since it's not joining two surfaces together, it did not have enough surface area to allow the capillary action to form a strong enough bond, so this resource said.

After reading your post I got a bit paranoid about using the wrong filler and went back and checked and it turns out the filler is actually nickel-silver. Is that the same as silver? Or do I purely need silver?

Live Wire 

Ha, lucky you, nickel-silver is perfect for this application! Its actually used a lot on stainless.
But, as you found out, it takes more heat (600-700 degrees higher than regular silver filler) to get it to flow, and its harder to file/finish.

roynyc

Ha that's a major understatement! I started with a hand-file and after an hour of work I barely made a dent so moved to the angle grinder, which was super scary since the one I have is kind of large and not built for delicate operations like this.

JRcyc

How do you know what size you need the tube splitter or Coupler? where can you get the rear cog to make a miche pistard be able to work with belt? did you need to adjust dropouts?