View Full Version : Technical: Silver Soldering Solder Threads Muzzle Brake

Chuck Rhost
August 14, 2000, 01:53
I'm about ready to silver solder a Tapco STG brake and was wondering if anyone has been through this process before and has any "words of wisdom" to pass on. Any "do's" and "don't's"? I almost have this project ready to shoot and don't want to screw it up now. Thanks for any info and tips.

[ July 22, 2001: Message edited by: gary.jeter ]

August 14, 2000, 02:13
Silver soldering is as much an art as a science. What is critical is that your solder, flux, and heat source are all appropriate for the temperature you will be operating at (>1100 degrees F.). Also critical is that your surface is absolutely oil free. I recommend sand blasting, then degreasing in alcohol, acetone, lacquer thinner or Methyl Ethyl Ketone (MEK). For most applications, a propane torch will not generate sufficient heat for high temperature solder. I recommend an oxygen-acetylene torch or MAPP Gas. Follow manufacturer's caution with regard to fumes. Most of the parts I have soldered turn a dull red at 1100 degrees, and cherry soon after.

In theory, you clean and flux the parts to be soldered, heat, then apply the silver solder and it will flow evenly into all the gaps in your work area, neatly and permanently attaching your parts. I have not been particularly successful with this method. I have attached DSA brakes using Brownells' "Silvaloy 355" (1/2 oz $15 #080-538-405) ribbon. I cut a piece of ribbon that matches the barrel circumference, flux the threads and barrel, wrap the ribbon around the barrel right behind the threads, then screw the brake on. Heat until cherry. Melts at 1145 degrees, flows at 1205 degrees.

My favorite is a product from Brownells called "Fusion" Silver Solder Paste. It is a paste that has flux and silver powder pre-mixed. It is excellent for attaching brakes. Simply apply the paste to the threads, screw the muzzle control device on, index it, and then heat with MAPP gas until it turns dull red. You will see the silver melt. Let cool, wire brush, and you're done. I have found it to be a little messy in the clean-up, but if the gun is to be painted or refinished, this is not a big deal. The STL 1205 Silver Braze melts at 1100 degrees and costs $26 for 1 oz. One ounce should do 10+ jobs. Stock number #322-100-650

August 14, 2000, 02:53
I bought gp's video and took his advice on the Fusion solder. It was a snap. I've done two Tapco brakes with this stuff and a MAPP gas setup from Sears.

It takes a total of three or four minutes of solid heat to melt the solder, and when it cools, it is on for good.


Richard Bird
August 14, 2000, 03:23
Reheating to the same temp should allow removal, or are the threads screwed--so to speak?

when it cools, it is on for good.

Chuck Rhost
August 14, 2000, 04:45
GP and Doc, thanks much for the info and tips...exactly what I was looking for.