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paul fowler
September 30, 2016, 21:00
I am having problems getting the triple frame soldered onto the barrel of my g3triple build. I am using the stay- brite silver bearing solder from brownells with the accompanying liquid flux. I can't get the stuff to flow into the joint. The fit is pretty snug. How hot do I need to get this thing for the solder to flow? I have mapp gas and mapp with oxygen as well. What am I doing wrong? I read that the JLD rifles had the triple frame tack welded on, is this an option? Any advice and or instruction would be appreciated.

Paul

gunplumber
October 01, 2016, 11:43
First, you can use much lower temp solder on the tripple frame. 400 F is fine. Nothing wrong with the 1100 you're using.

Which brings up the confusion over what you're actually using. Stay brite is a harris product - MP around 430. It would be perfect. But the paste is a Fusion product with an MP around 1100F and doesn't use separate flux. I use silvaloy 35 or 45 with staysliv flux. These are Lucas Mihaupt products.

heating 400F solder to 1100F will fail
heating 1100 F to 400F will fail

You can get to 1100 with MAP but it takes a while.

So, here's what I do.

Drill two holes in the 3-frame at 6 o'clock and thread one of them for a #6 or #8 machine screw. Set the front sight to what looks like TDC. Tighten the set screw. Complete the build mechanically centering the rear sight. Shoot at 25 yards. If you are not windage aligned, loosen your set screw and move the front sight until you can zero. Lock set screw in place.

Return to shop and heat triple frame - feed solder into hole. let cool. remove set screw or just cut off and sand flush. Now drill your sling mount hole and weld or press the end of it.

CG&L
October 01, 2016, 12:05
Not to get off topic but it appears the OP's dilemma was solved

Is the Stay-Brite solder good enough to solder a flash hider to a barrel?

ATF 'good enough' to make a 14.5" barrel the required 16" with flash hider

hkshooter
October 01, 2016, 17:41
Not to get off topic but it appears the OP's dilemma was solved

Is the Stay-Brite solder good enough to solder a flash hider to a barrel?

ATF 'good enough' to make a 14.5" barrel the required 16" with flash hider

ATF calls for permanent. ATF defines silver solder (1100 deg) as permanent.
Stay-brite is 430. So no.

paul fowler
October 02, 2016, 00:39
Mark,

Thanks for the tutorial! I got the set screw installed in the triple frame and will shoot it tomorrow. Hopefully I can get the solder to flow using the method you described. I'll let you know how it goes. This is my first G3 build. Much more to it than building an FAL.

Paul

paul fowler
October 03, 2016, 23:47
Got everything together. Shooting point of aim. Thanks for the help. Had to pogo it the first couple of shots to get the bolt carrier forward, but after that it functioned well and went through the mag with no problems.