? for welders

can 300 series stainless be silver soldered ?
this concerns a return line in a gas tank sender, but i don't know the exact series of the material, other than it's some kind of 300 stainless. if i had to guess, i'm thinking maybe 318.
as always, TIA !

With proper cleaning and the proper flux for soldering stainless, yes it can be done.

You could also braze it.

there are several videos out there that will show how to do both.

thanks ! i will have to check those out.
the reason i was asking, i was getting conflicting info from the local welding shop gurus. they said tig only, but the part clearly shows it's a sweated [correct term ?] fitting, while the other part of the shop said stainless solder, of which i never heard of, so ?

With silver solder the joint is only as strong as the silver, with more silver in the solder making it stronger but also upping the heat needed to do the job. Since it's just a return line silver soldering it will be fine. Did that years ago when I put FI in my Diplomat. I think the factory swaged the joint and used the soldering to seal it, if you could replicate that it would be best but even if you couldn't I never had an issue with my job.


It's been 20 years since I did that particular job so the details are not as clear as they might have been.

i'm going from 1/4" return to 3/8 or 1/2", depending on the area i have around the line in the sender flange.
it will be swaged, as i have done that to factory steel sending units many times, and used silver solder [the kind you find at good hardware stores and welding supply places.]

Sounds like you have it sorted out, shows us an after pic when you are all done, thanks

will do, but it may be a while.