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View Full Version : Anyone familiar with "brazing"?


nomaspescado
November 8, 2004, 10:21 PM
Hello,
I'm working on a pet project that will involve permanentely brazing a heatshield to the shotgun barrel.
Is the basic oxy/mapp gas brazing/torch that you can buy at Home Depot the one that will work for me?(The small tip sure does look small and unforgiving to me). I have the non-running type brazing paste that I bought from Brownells along with Templax which is an indicator as to when the proper temp has been reached...1400F.
I would love the satisfaction of doing this myself, but obviously don't have any experience doing this proceedure. I would like to kow if there is anything in particular to watch out for...or any advice??
Thanks for the help.
Steve

mete
November 9, 2004, 01:16 AM
Many things to consider - Size , shape, and how it will be connected , what type of shotgun. Barrel will have to be reblued, possible warping problems.Haven't used oxy/mapp or seen torch so can't say if it's enough.

nomaspescado
November 11, 2004, 12:21 AM
Ok....So nobody here has ever brazed on a front sight to their shotgun barrel before??

dfaugh
November 11, 2004, 09:00 AM
work pretty well for many gunsmithing tasks...With one problem...The oxygen cylinders don't last long and are bloody expensive...I bought one, used it on a couple of projects (most notably bending, reshaping and brazing a bolt on a Mauser)...Also, used for a few other tasks, both gunsmithing and not. Total time in use = about an hour...And for what I've spent on oxygen bottles, I coulda bought a used oxy/acetylene setup(and I soon will), the Mapp gas lasts ALOT longer. So if you anticipate using it more than occasionally, go for a full on oxy/acetylene rig.

Now, I'm wondering about your nomenclature here when you say brazing....Brazing would normally imply using a brass alloy rod (as I did with Mauser bolt)...For attaching sights, most people would use silver-solder, not brazing(but I've heard MANY people use the term brazing for silver soldering). Silver solder is not as strong as brazing, but plenty strong for most things. Its also alot easier when you have close-fitting parts, like a front sight, as the silver-solder flows very nicely(wherever you have a clean, fluxxed surface.) Silver solder flows at a much lower temperature, so you needn't worry so much about warping a steel part, or more importantly with guns, annealing (loosing the temper or hardness)

When I was in the custom/race car business I had about $10,000 worth of welding equipment (mig, tig, stick, torches)....and while my recollection is fuzzy 1400 degrees sounds way high even for brazing, but I may have forgotten...But I'm sure that's enough to possibly 'cause warping/distortion of the metal, and definitely enough to remove the temper from hardened steel.

If you've never welded/brazed/soldered with a torch before, practice on as many scrap pieces as you can, with similar thicknesses to your project(one of the hardest things is attaching thin material to thick...easy to get thin stuff too hot, even melt before you get thick stuff to correct temp). It's not that difficult but to make "pretty" and strong joints takes practice. You might see if any schools in the area offer basic welding courses--probably worth it (although I was completely self-taught on mig/tig etc., but I went through alot of scrap before I was good). Or, check local library for books, I recall I had a couple reference books, but I think they mostly applied to various alloys, specialty welding. But library may have more basic books. I also relied on my local welding shop for advice in alot of areas, most have some really knowledgable guys there, they may have classes too.

In short, you can certainlydoo it yourself, and have the satisfaction of learning a new (useful) skill....just proceed slowly and carefully

nomaspescado
November 11, 2004, 10:53 PM
dfaugh,
Thank you so much for responding to my question. You're the kind of person I was hoping to get advice from.
It sounds like I my have recieved bad advice previously when I was told to use the non-flowing type of brazing paste sold by Brownells. It needs to get up to between 1000 and 1500F to work.
It is better for me to find out through this forum from experts like yourself than to ruin a perfecly good barrel on my own.
I will definenitely look into getting more info at the local library.
Thaks again,
Steve

Danindetroit
November 15, 2004, 05:32 PM
Noma it has been a long time since I welded or brazed. I thought that I remebered that there were a bunch of types of braze. It also came in strengths like bolts, 60,000 psi up to 120,000 psi, I think the highest weld strenght was 80,000 psi. I thought I read that some tubualar frames for races cars were brazed. I hope this link can better help you figure out the best product for your need. I can get the name of the book and maybe you can order it from Barnes and noble. Here is a link to a brazing site hope it helps.

http://www.handyharmancanada.com/TheBrazingBook/bbook.htm

IceMan_1
November 16, 2004, 05:50 PM
Hi Nomaspescado , are you installing a sight or a heat shield? If its a heat shield you may be able to use JB weld between it and the barrel , this stuff is plenty strong depending on how it is used . As far as a front sight I have put the bead type on by drill and tap a hole and screw in , don't know what type of sight you have . Hope this helps .

CutNShoot
November 17, 2004, 01:29 PM
There is a low temp silver solder that is used to solder guards on knives it keeps the heat low so it wont efect the heat and temper as you have to heat treat before instaling guards of silver ! Pops knife making supplies has it!http://www.popsknifesupplies.com/ I have never used it on guns but it would probly get the job done. He also has the flux paste and is a class type guy with a world of info he dosent mind sharing.give him a ring his phone number is on hios web site.