Soldering- Lesson Learned

Sticks

Well-Known Member
I'm a newbie knife maker, only 4 1/2 to date. Its the 1/2 that 's causing the problems. I've soldered a nickle silver guard to 440C, a brass guard to A2 and a 304 stainless guard to A2, without mishap (other than too much solder and cleanup). The latter guard I even used Menard's silver solder. Each time I used Staybrite flux. Last night I tried to solder another 304 guard to A2. This time I thought why not use Radio Shack flux and "silver solder". Well the same solder that used before just beaded up and refused to stick. So lesson for me was make suer you use the right flux.
 
good lesson. soldering stainless is a bugger until you get the right combination and learn to not burn the flux...
 
I'm thinking of getting some silver model paint and just painting the joint! Argh! ! Tried again and this time with the right flux. The solder "filled" the largest gap at the bottom of the ricaso, but wouldn't fill the tight, almost zero, gaps on the sides. Maybe burned the flux, or .... The knife on the right turned out OK but the one on the left, well you can see the problem.

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I use JBweld myself. I hated cleaning up after soldering.
 
I'm with Tracy and James. JB Weld is sooo much easier and the excess can be cleaned up with a little WD-40 on the end of a q-tip before it sets.

Doug Lester
 
You guys are making me think /I/ should go to JB Weld for this type of thing too... I've been fighting soldering thinner brass ferrule with thicker brass guard using medium & easy silver solder. Not fun. As for flux, I've had more luck mixing up a slurry of borax and water than with the commercial flux I've got?!? So JB Weld is sounding attractive.
 
Well Sunday I bought a soldering iron. Thought I could finesse the solder into the tight joints if I used the Staybright flux. Well, no luck I couldn't even push it in when the solder was liquid. So I'm thinking that the inside of the guard slot was not clean, i.e. blue dye, rouge or something. So next time I'll clean the inside of the guard. I can't figure what else is going on. And I use JB weld for bolsters, but hate to quit on soldering guards because I can't do it.
 
Silver solder is MUCH higher melting point than electronics or plumbing solder - up around 1350f. Takes torch work.
 
Mike-Sorry I miss-spoke. What I used is the lead free type of solder, not true silver solder.

Jay
 
Hey Jay, I just soldered on three GUARDS with the stay bright solder. It is kind of a pain to clean up if you use to much. Your write about keeping it very clean that helps.. The key is keeping those gaps to a minimum and using as little solder as possible.
 
Thanks Doug. This the first of four guards that I've soldered and had this problem. I think I didn't clean the inside of the guard well enough. Also I tried using rosen cored solder the first time. Rosin is no good for stainless. That may have contaminated the joint between the guard and blade. Once that occurred even boiling the peened guard and blade in baking soda water didn't seem to help. Ironically the solder worked where I had the largest gap at the bottom of the guard. The sides, where the solder didn't stick are really pretty tight. I wish I had a true macro lense. I could post a better picture.
 
I'm a newbie knife maker, only 4 1/2 to date. Its the 1/2 that 's causing the problems. I've soldered a nickle silver guard to 440C, a brass guard to A2 and a 304 stainless guard to A2, without mishap (other than too much solder and cleanup). The latter guard I even used Menard's silver solder. Each time I used Staybrite flux. Last night I tried to solder another 304 guard to A2. This time I thought why not use Radio Shack flux and "silver solder". Well the same solder that used before just beaded up and refused to stick. So lesson for me was make suer you use the right flux.

I think I just figured out what you already did about the flux. I got the water soluble flux from Home Depot (the only flux they had) and the Metal Work solder, and the flux burns up before the solder reaches temperature, and then the solder just balls up and floats. I'm gonna try it one more time before I go to the JB weld, and heat it slooowww...
 
You may well be right. I thought I just didn't do a good job cleaning the inside of the guard, blue marking die, etc. before I peened it on. I read somewhere that if there is a place that you don't want solder to stick- coat it with pencil graphite. So solder is pretty fussy stuff. I just used JB Weld to attach bolsters to a kitchen knife (I knew it would end up in the dishwasher.) its held up just fine after a few "dishwashin's".
 
I said I was gonna try the solder one more time, but I lied. I walked right back out to the shop and found my JBW... :) Bolsters are now bonded, clamped and sitting until morning. I wonder what I could use this flux and solder for now...

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Brad,

Ha! It'll make your shop look professional. Hide the JB Weld. By the way I just bought some more JB today. I ain't soldering unless I have to.

Jay
 
Ok, I learned something else... JBWeld does NOT stick to brass. At least not the brass that I have. :( both bolsters popped right off this morning. Now I am back to either soldering or maybe Gorilla Super Glue. I know i have used the Gorilla brand before and it holds up really well. After I get the pin peened, there "shouldn't" be any problems.
 
Brad,

You've probably seen it, but somewhere there is a tutorial on soldering bolsters for slip joints. That's where I picked up the "solder won't stick to pencil lead". Seems to me that the bolster and liner were "tinned" before being soldered together..

Jay
 
Brad,

The tutorial was posted by Bill Vining on our Knife Dog's forum, under tutorials, "How to solder bolsters to slip joints."

Jay
 
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