Originally Posted by bulgie

OK, as long as you know that soldering is not strong enough. Even silver-bearing solders are not strong enough for a brake bridge. You need to silver braze a bridge. But a lot of bikies call that silver soldering — it's sort of a traditional jargon in the bike world that's technically inaccurate, but it's fine as long as you actually braze it!

Most silver brazing alloys are a bit on the "runny" side for a brake bridge, but they can work if you're careful, with good fit-up, prep, cleanliness, the right flux and flame etc. The higher silver content fillers, 56% for example, tend to be the runnier ones, not good for fillet-building, so I would choose a bit lower silver content, say 45%.

Some bridges come with reinforcing plates that have a little spigot that goes up inside the bridge, like an inside lug, very much increasing the "wetted area" for the silver to grab onto. While that is not strictly necessary, I think with silver it's a good idea. It can help with the safety margin, in case your fit-up, prep, flux or brazing skill are anything less than optimal.

Mark B in Seattle