How should I solder stainless on a 6A blade?

[jhunter77]

I have piddled with knifemaking for a while and now want to make a good knife that looks and works good. I got a 6A blank from texas knife makers and the stainless guard. What should use for flux and please go into detail on the prep work. Thanks for the help.

 

[Patrickknives]

I would slide the guard into place and scribe a line to mark where it fits, you will need to rough the surface behind the guard (away from the blade). I use silver solder most recommend stay-bright solder and flux. I have been using a off the shelf type but plan to swithch when this runs out. wrap the blade in a we cloth to prevent heat for changing the temper and put some flux in the blade (only rough portion) and inside the guard. Assemble, cut some small pieces of solder and place at the joint, very small like this size -- maybe 4-6. Heat from below just until solder melts, it should pull into the joint. If not try to move a bit with a piece of brass rod. Do not keep heating once it melts there should be enough heat to keep it liquid for a while. Try to clean up as much as possible with fine steel wool while liquid. Good luck, soldering stainless is tough.

 

[Stacy E. Apelt - Bladesmith]

The solder and flux has to say "For stainless steel" or it won't work well. The common advise about roughing up the surface is good for glue, but not for solder. The surface should be sanded smooth (400 grit) and cleaned to an absolute cleanliness. Think of the solder flowing- do you want it to have to run an obstacle course of micro hills and valleys, or have a smooth flat sprint. Use heat sparingly, especially on stainless.A heat gun works well.
Stacy