As a hand-brake 'handle' is presumably not subject to high temperatures, why not 'tin' the parts with soft solder and then sweat them together. Unless it's on an 'edge' – this should make a very strong joint and would be much easier to do.

Regards,

IanT

Once silver solder has been melted it takes more heat to melt it the second time due to a chemical change in the metal so depending on your heating equipment you may not get it upto temp the second time.

When I have flat areas to solder I put a few punch marks onto one surface and the small burr raised around the punch mark leaves a slight gap that the solder can flow into and will not close under moderate clamp pressure.

And the bit from the link that matters

"Most joints are self-jigging but occasionally components may have to be clamped into position particularly with sheet/sheet joints. Clamping effectively removes the joint gap. Maintain it by centre punching dimples into one of the sheets or place a piece of foil in between"