Gunsmithing Silver soldering bolt handle

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Just been watching a setup over on the picture gallery of a guys setup for installing a bolt handle, very good little fixture and Benchduck, if you see this, thanks for replying with more pictures, you might also chime in on this one if you can. How is the solder put on, is it solder paste thats used or how do they get it underneath where its not visible.
 
Re: Silver soldering bolt handle

When I do it I use Silver Solder that is flat and about 1/2" wide, like a ribbon, just cut off what you need and put under the bolt handle and heat it up.
 
Re: Silver soldering bolt handle

Silver solder bonds on a "capilary action". If the parts are good and clean you flux between the parts. (I also use the ribbon type, mostly. But I have some wire as well.) Then when the parts are at temperature the flux will almost suck the solder where ever the flux has been and is heated. I usually place a small bit of the ribbon solder between the two parts before heating.
 
Re: Silver soldering bolt handle

Thanks guys, now the question is, whats the best silver solder for this job. There seems to be all sorts of silver solder available, brass, quartz, platinum, Which one do you recommend
for bolt handle installation.
 
Re: Silver soldering bolt handle

If you dont plan on removing it then a nice tig weld would be good. SS just doesnt hold up real well. But if you want you want you just need and solder that will do up to 13000 psi. You can get the 18000 stuff but it has a much higher melting point.
 
Re: Silver soldering bolt handle

I spoke to the guys at my local welding supply house. I can't remember exactly what I paid for it. But I do remember that it depended on the price of silver on the market that day.
 
Re: Silver soldering bolt handle

Though I would reccomend a tig weld as well, anything over 65% silver will work, higher content up to at least 90% is better. (I've not tried higher.) I've even used high cadmium (85%) solder in a pinch with good results. I use either ribbon or 1/36" diameter or smaller. It will generally pull toward the heat. "Tinning" can be of use, though not absolutely necessary. Practice on some scrap metal is usually a VERY good investment even with silver prices this high.

Hope I helped,

WS
 
Re: Silver soldering bolt handle

I "tin both parts, re-flux them and then with the parts assembled heat them back to temp, and go around the edge with the ss. a small amount will be sucked in for a solid joint. As I'm using High force 44 which is a bit lower temp solder I also put in a machine screw at the top of the handle to lock things down better. Haven't had one come loose yet.
 
Re: Silver soldering bolt handle

i made my jig for tig welding its so much easier to set timing and get full cam with that jig i did silver for years with ribbon but ss will give headaches but my jig was diffrent i looked for pics but cant find them will ask the guy i gave it to to send me some i sent my jig to dave kiff hes going to start making them i will post a video on youtube with mine when i get it back ive got three 338 to do and i will try to find one to solder. i want to say one thing you can not put on a bolt handle the right way with out the action theres a asshole up north (way north) that does they dont time right and some times wont close i dont work for the public so iam not trying to get his business nathan dagley or kampfeld do good work
 
Reviving this old thread. When using the silvaloy ribbon silver solder sandwiched between the bolt and the bolt handle, do you need flux? if so how do you apply? Any guidance on this process?


Always use flux. White for carbon, black for SS. Make sure parts are clean and it never hurts to have a small "tooth" on the surfaces. An 80 grit roll at low rpm will do this nicely.

Heat to dull cherry red. You'll know when if you watch the flux. It'll froth up at first, then bleed out into what basically looks like a candy base. Near colorless and thick in viscosity with a gloss that almost emulates automotive clear coat. Between that and the color change in the steel, your hot enough to go ahead and apply the solder (if using wire) or just continue with the heat carefully and observe the foil/ribbon type begin to melt. I use a "rich" flame. Its just to avoid the risk of scorching parts.

Hope this helps.
 
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With the process you described, the alignment will change a bit when the ribbon melts. That’s what I’ve used professionally (not rifles), but a sprung element or a weight to push the bolt onto the handle or vice versa will mitigate that as long as you prevent the angles from changing.

I’ve done mixed material brazing with some pretty nasty combos. Mismatches in thermal expansion coefficients and close melting points of substrate and braze alloy tend to cause the most problems. Stainless and carbon steel in combination shouldn’t be too bad, but it’s probably worth running a quick test and looking for cracks.
 
Last edited:
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With the process you described, the alignment will change a bit when the ribbon melts. That’s what I’ve used professionally (not rifles), but a sprung element or a weight to push the bolt onto the handle or vice versa will mitigate that as long as you prevent the angles from changing.

I’ve done mixed material brazing with some pretty nasty combos. Mismatches in thermal expansion coefficients and close melting points of substrate and braze alloy tend to cause the most problems. Stainless and carbon steel in combination shouldn’t be too bad, but it’s probably worth running a quick test and looking for cracks.


Just to add to this excellent comment:

Never, ever try to accelerate the cooling process when soldering with any kind of "coolant". Just as with a weld, it's poison to immediately dunk something in water, oil, whatever. The rapid change in temperature can/does cause the joint to fall apart just due to expansion.

Keep a coffee pot close by and go enjoy a cup between jobs. :)

Have a great weekend all.