Stainless soldering?

yes, getting it to bond.

Any suggestions? Making SCA coronets, and need to solder internally threaded tubes to the inside. No access to TIG at the moment. Lower temps mean less cleanup. Plus I'm looking a .100" OD tubing threaded to

Good agressive flux?

How about some Air conditioning brazing sticks. Lower temp and self fluxes. Try on scrap.

Martin

Mart> Ernie Leimkuhler wrote:

Physically clean (abrasion, wire-brushing) and chemically clean (flux). I'd actually suggest 95-5 tin antimony over electrical solder for this job. One approach to the cleaning is to wire-brush (or scotch-brite) with flux already in place, so the flux keeps the oxygen off the freshly abraded area to some extent. The best low-temp soldering flux I've used for stainless was Eutectic Castolin 157, but that was decades ago, and products may have changed. It was a pink liquid, and was fairly nasty as you'd expect a very aggressive flux to be. A web search says they still make it.

Zinc chloride (generically "acid flux") is probably the most easily available somewhat aggressive flux, and should work if you are careful.

When soldering, use a torch, and stay in the reducing region of the flame - if you have an OA torch, use a long soft feather (rich mixture). Good ventilation would be a smart move.

Clean up well afterwards, if you succeed. Anything nasty enough to effectively flux stainless is not something you want to leave on the end product.

Pewter would offer a much more period sort of product that would be also be easier to work with, if you care about that at all.

Low temp silver bearing solder is a better choice. Stronger, with a better flux.