Hi Ethan,

Soldering stainless to stainless can be problematic. I know that Brownell's sells solder designed for this purpose, but I don't think the Brownell's solder is a good color match for knife work.

I've sent messages to a couple of knifemaker friends of mine who may have experience with stainless to stainless soldering. I'll post any information that I get back from them.

Okay Steve hope you get some responses. I tried soldering again tonight and here is the way I went about it:

First I sanded the blade with 400 grit sandpaper in the places that I knew the solder would touch, Next I washed both the blade and SS guard with acetone to clean them up. After that I placed the guard on the blade and put a heat sync putty on the blade to keep from losing my temper. Then I put a drop of Stay-clean flux on each side of the guard and spread it around the blade with a toothpick. I also placed two small cuts of solder wire on top of the guard so that I would know when I was at the right temperature. Finally, I began heating until my solder began to melt and I melted more of my solder onto my guard but I got the exact same result. The solder didn't skate right across like it wouldn't stick at all, but it wouldn't flow down through the guard like it normally does with nickel/silver. I know for certain that I am not getting this too hot because I was extra careful about this. I also cant seem to get the solder to want to stick to the blade as well. I am beginning to think that I might be using the wrong type of solder or flux, Is this a possibility? The solder I am using is silver bearing solder containing no lead. It is also rosin core which I bought by accident but I didn't figure that would make any difference.

Ethan Lee

Ethan;

Soldering stainless has its problems. Some things for you to try to narrow down the problem.

Use a small piece of each steel and put a run of solder on the surface; if it doesn't tin up each of them separately, it won't do them together.

If they both tin up nicely it's a heat problem on the knife that is the culprit.

If they both don't tin up well, try this. Sand the parts clean, clean with acetone, then scrub the parts in HOT ivory liquid/water using a clean cotten cloth.

Then solder immediately. Ivory will clean much better than acetone.

If you still don't get the solder to tin up the pieces, it's a solder/ flux issue.

Hope this helps.

Mike

Hi Ethan,

I have no experience as to soldering stainless to stainless, but after reading your question I did a google search for "Soldering Stainless Steel". Turns out there are a ton of sites devoted to you question. Looks like they al agree that it is a challange. Check it out and maybe you can find an answer there.

Hope this helps

Dale

Hi Ethan,

I checked with Todd Davison and Harvey King about the solder that they are using. Both of these gentlemen use Stay Clean flux and Stay Brite solder. Todd makes awesome folders and solders all of his bolsters to the liners with this solder. Harvey is a fine stock removal maker and he too uses Stay Clean and Stay Brite to solder stainless guards and bolsters to his stainless blades.

Almost certainly, your issue with soldering is caused by using an acid based flux with a solder that has a resin based flux core. Stay Clean flux is Zinc Chloride based and is an acid type flux. Resin based fluxes are generally used for electrical connections were the flux residue cannot be thoroughly cleaned after soldering. Acid fluxes will cause corrosion if the flux residue is not thoroughly cleaned away after soldering.

The Stay Clean flux is fine for knife work, but you should try using Stay Brite solder instead of the resin core solder. Many of the knifemaking suppliers sell a kit with liquid Stay Clean flux and Stay Brite solder. Here's a link to the Jantz Supply solder page. Jantz Supply / Solder

Another thing that you may want to try is using a heat gun (like is used for striping paint) as the heat source for soldering. The flame from a torch is too hot when directed at your flux. The flux will burn and then will no longer work to dissolve the oxides on the metal.

Okay thank you everyone I will order some stay-brite solder. I have never had a problem soldering nickel/silver with the rosin core, but soldering stainless must just be an art in itself. I will let you guys know as soon as I find out how it works thanks again!

Ok I tried using stay-brite solder and the result was much better but I still was not able to get the solder to flow between the guard and tang like I can with nickel/silver. It just didn't seem to want to penetrate. I got all my blades soldered but I am still looking for a solder that can fill up a solder joint like I think it should. It just seemed to want to stay on top of the guard and blade. Does anybody know of a solder that can do this?