hard solder 650 degree C what do I need to melt this?

Before lighting up the torch to melt this solder, consult a jeweler or goldsmith for an expert opinion. There are several risks:

1. Melting the frame where the hinge is attached.
2. Without a heat sink, melting any non-metallic items on the frame which cannot be removed.
3. Opening up other nearby joints (if any exist) from the heat.
4. Warpage of the frame such that the lenses are no longer captive.

There may be softer solders with lower melting points which would serve as well.

The problem with jewelry-size silver soldering jobs is that of overheating and damaging surrounding areas; to the extent of "unsoldering" components in those areas. Generally, the problem comes down to one of control rather than temperature. Check

for an excellent small torch system.

Bob Swinney

No, it is VERY unlikely you could get air at 650 C from this. You might be able to find an extremely hot soldering iron that will reach these temperatures, but it might still not be hot enough to melt the solder on the part to be repaired. I think a torch is the only way to go, but you'd need a micro torch to avoid melting the whole piece, if it was assembled with a solder or low-temp braze originally. (Maybe there are no other soldered/brazed joints on that part, if so then a larger torch might be safe.)

Jon

Something that tiny can be immersed in a small-torch propane or MAPP gas flame, which should do it.

Since it is on the temple part, it's a lot easier than if it were on the frame itself. I fixed one on my son's glasses a couple of weeks ago. I filed up a new hinge half from a bit of brass and drilled a hole about

1.4" deep in the back end to suit the temple rod (which happened to be round.)

I soldered it in with non-lead solder like this stuff from Radio Shack, and a bit of acid flux (tinner's fluid). Plenty strong for that sort of application.

You can probably remove the busted hinge from the temple piece with some patient judicious filing.

For something that tiny you could get all the heat you need by borrowing a pipe smoking friend's butane pipe lighter, or even using an alcohol lamp and a purchased or homemade blowpipe.

If there's a plastic earpad on the temple piece, fasten a small G-clamp (that is what you Brits call them, isn't it?) in the middle of the temple piece to sink the heat so you don't melt the plastic. It wouldn't hurt to wrap a bit of wet cloth one the "cold side" of that clamp "just in case".

BBL,

Jeff

I would farm this out. with the right tools this job is a snap. with the wrong tools you probably scrap your spectacles.

Do a Google search. Optical frame repair UK came up with over 67,000 hits.

Ask your local optician about the job. This might be a pleasant surprise at how cheap this job can be done.

A file or a small grinder.

In my part of the world I believe the optical people use 'easiflo' silver solder/brazing rod for spec parts. Melts at 610degC. Well tough enough.

Probably. The deciding factor is how much of a heat-sink is the part to be attached to. Being a temple I guess it'd be alright.

Where are you getting the fresh hinge from?

Don't forget to vote next year.

Bri