Brazing removal?

[Jordan Baker]

Anyone have some suggestions on how to remove brass brazing? My latest project has had brazing applied in effort to fill in some holes. I'm hoping to be able to remove it to recover the same holes.

[rob love]

Personally I hate brazing. Why fill with a non-ferrous material, when you can fill it with MIG steel. No doubt it has it's place, but personally I have not found it.

Brazing gets right into the pores of the metal. I'll grind away as deep as I can, then I have to live with the splatter as I Mig over top of it. Not ideal, but it's all that I got.

Waiting to hear from someone with more knowledge on this subject as well.

[chris vickery]

Being that it is applied to sheet metal, removing it without warping things is difficult. Personally if you can grind away with a sanding disc to reveal the hole, I would just drill out the remainder. Otherwise you can try to reheat the area and hope the brazing material will drop out of the hole.
Back in the day it was the best way to weld up sheet metal over Stick welding and was simple enough Bubba could do it at home with nothing more than a set of torches.
It is effective for items like casting etc that need to be rebuilt.

[rob love]

Chris: Yes, bubba could do it, but at the same time buba always made an irreversible mess. He was, after all, using braze because he couldn't control the heat when he welded.

Personally, I have always preferred steel for steel. If you are decent at the torches, and use the right tip with the right heat, you can usually make it work. If you have access to a MIG, even one of those Canadian tire ones that use common house voltage, you can take all your brazing rods and toss them in the garbage where they belong.

[Jordan Baker]

So if I were to use a torch, would that work for simply hearing it up until it melted out? I've never brazed before so I'm not sure how it all works.

[rob love]

Likely not. Brazing it kind of like properly tinned solder....it leeches into the metal. You will get rid of about 80% or more of it by reasonable heating, but you won't get it all. When you try to weld over it with steel, either by gas or by mig, it will spit like water in boiling cooking oil.

Did I mention I hate brazing?

[Lynn Eades]

Jordan don't be blinded completely by Rob.
I have come across a number of bad and failed brazing repairs over the years, so I know exactly where he is coming from.
Brazing was a regular method of repair a few years back, used in many different ways on many and varied materials.
I'm not skilled in this area but here are a few uses that might be of interest.
"Silfos" for welding copper.
Various types of "Easy flow" for sweating components together with next to no extra material showing used to join copper to brass, steel to brass etc. used in refridgeration(high silver to prevent vibration cracking) lower silver content (cheaper) in plumbing use.
Wear brazing. We used to use it all the time for repairing cracked and chaffed hydraulic pipes.(not what it was made for)
The ordinary type of brazing Rob refers to covers the whole spectrum of materials. Results can be very good, but where for instance a crack in cast iron is brazed, the results might not be so good.
The success of this type of repair is often hit or miss and I tend to run with Rob in this area. It usually requires a skilled welder along with some good knowledge of just what the cast is.
(many types and problems)
I think brazing has faded from use because;
We are a more throw away society.
Because alternative welding methods have evolved.
The cost of labour has tended to do away with "we'll try and fix it first"

[cletrac (RIP)]

If you get the brass molten then use a hand wire brush to wipe it away you'll get rid of most of it.

[rob love]

Lynn

I will bow to your points about it having it's uses. But where it does not belong is on huge door and fender patches, or trying to join two halves of a cast hand-crank together. These are the kinds of jack-ass repairs I have had to deal with over the years. I never could figure out how these baboons managed to get the torches to light, besides not burn down the shop.

[colin jones]

Hi Jordan, I have done this in the past and it works quite well but you do need to wear some protective gear. Use an oxy on lowish heat and use your compressor with a point jet and blow it away. It won't get rid of every bit but most of it. You can direct which way you want it to go.
Colin.

[Lynn Eades]

Rob, I am on your side!

[Richard Farrant]

Some of the posters here, seem to describe brazing as the work of the devil. I have been hands on in repair work on vehicles and machinery for 49 years, brazing, bronze welding, etc. were all methods taught to me and have used them during my working life where required. There will always be a bodger around who misuses techniques making it harder for the next person to recover a bad repair, but that is life.
Just so some of you can look deeper into the technique, here is a link to a company who supplied products in the UK:
http://www.weldability-sif.com/media..._technique.pdf

[rob love]

Stuart: Read post #9 and you will see what repairs I am talking about. Pretty sure we have all seen them. Big globs of brass with the flux overheated and now part of the braze. No real strength. As I said in my earliest post: no doubt there are proper uses for brazing, but I haven't found them. Lynn has given some good examples about where braze actually belongs, as have you. But are these the kinds of things the average CMP restorer is doing? Richard, I would suggest your proper use of brazing is the exception and not the rule. Most of the brazing I have been exposed to is not the kind of work anyone should be proud of.

I'll add a shot or two of items at work waiting for repair from the brazing bubbas.

[chris vickery]

Tig weld everything and solve all your alloy metal problems...

[Darrin Wright]

Previously, I have had to do the same thing.

Thinking back to my trade training days, my instructor always said, 'not too much heat or you will burn the braze and it will not be effective'.
So with that in mind, I use too much heat and burn it out at the same time as using a wire brush to pick up most of the molten particles, flicking them out.
Wire brush/wire wheel after.

I have learnt some info from this thread, from the older hands- thanks

[Stew Robertson]

Easiest way is heat with a torch and brush it with a wire brush the clean it up with a grinding disk
I have used it and removed it and in the right place serves it purpose

[Jordan Baker]

I ended up just cutting the old repairs out and welding in a new piece.

[Jordan Baker]

New piece almost done being welded in.