Stainless and solder

[noddaz]

I should have asked first, but oh, no. I order up some screws and nuts and think "I will get the stainless because, well... Stainless". Then I try to solder it in place. Hmmm.
So I look it up and you CAN solder stainless, it just requires a bit more effort to do so.

[chrisguyw]

Hi Scott, Soldering stainless is not that difficult, (as you seem to have discovered) but, you do need some different materials than when soldering wire/brass.

While paste (rosin) flux is fine for wire/brass, you really need liquid acid flus for stainless (acid flux is also much better for wire/brass ) , and while 60/40 solder is OK (especially for our 1/32 cars) silver solder is certainly stronger, but, does require more heat.

Additionally, for any chassis work, the fine pointed tips that come with most soldering stations do not transfer sufficient heat........you should use a 1/4 chisel tip with an iron that provides a minimum of 45 watts...more is better !!

It goes without saying that the surfaces to be soldered must be completely clean, and your iron tip must be clean and tinned as well.

Cheers
Chris Walker

[Slotspeed]

I used to solder small stainless parts made from approx 1/32 thick or about 0.6mm sheet, we used this pink colored liquid plumber's flux, very clean iron tip and work piece as Chris also mentioned. I forget how we cleaned the work pieces but they must be very clean and probably given a wipe with IPA or acetone, I forget which. From memory we just used 60/40 solder, will ponder this and try to think if there was anything else we had to do. But it can be done with very neat results, just need to get the prep work done right.

[4424ever]

I’ve soldered stainless clean parts,lucky bobs flux and 60/40 are all a slot car needs

[Bill from NH]

Two other acid fluxes that will work well with stainless are Harris' Stay-clean & Oatey's Liquid Flux. I find Oatey's in the plumbing dept. of my local Ace Hardware store.

[noddaz]

I probably have Oatey's in my plumbing torch box.