Rustoration query

[gulf908]

I am part way through my never ending cleansing and resurrection of my little treasure.
My expert panel guys have told me that they have had to junk my two front and one rear fenders as they are warped due to having brazing repairs done instead of welding corrections,when the car was repaired some twenty years ago.
Needless to say,the car has been carting around an unknown amount of filler since then to correct the wavy panelwork.
I have never heard of brazing repairs before on panels.
Can anyone pls illuminate me on this process and its reasoning.
Restorers ? - Nick Moss ?

Cheers,
Dennis.

[Paul Schooley]

If I'm not mistaken, mig is the recommended way to do repairs. The gas heats up way too much area and distorts badly in the wrong hands. That said, I'm sure there's others here that could better answer your question.

[pu911rsr]

Well I am not a welding expert but I don't think you can braze steel, too low of temperature. Brazing is for material like Bronze and Brass.
Phil

[911quest]

Twenty years ago brazing was the only real option if you look at old body repair manuals that was state of the art for the day if done correctly it still is as good as or better the mig welding kinda of a lost art like lead work the Most body guys today don't want to take the time to grind out the old brazing, cause you cant weld to it

[flat6s]

You can braze steel. Motorcycle frames (vintage) and monocoque frames (i.e Jaguar C/D/E-Types have brazed front frames. You use a welding torch and weld with a rod which I believe it is a mixture of bronze/ copper and other metals but I am not exactly sure. I would have to check the composition on the tube in the gargage. Brazing is very strong and old school. The color of the weld is goldish (bronze/ copper??). The trick is to heat the substrate just hot enough to melt with the rod and form a nice puddle. I have fully repaired the metal under my friend's 71 Targa rear glass by fabricating a new piece with the upright lip. If done properly the is very little distortion and grinding. The welds are smooth and flat (since it melts nicely) and is much cleaner than a MIG seam.

I would not use it on structural areas as I do not know how strong the welds are. But then again... Jaguar made all it's frames that way and they held up fine, even under racing conditions.

I have also brazed many suspension pans after they were tacked in with a MIC. Use little heat and don't stay on one section too long. Rotate the area you weld. Once you used brazing you will NOT be able to weld over it with a MIC! It is also called "hard soldering".

Haynes has a neat welding book.

[neilk]

Before my car was repainted, my restorer thought for some reason that the car might have been hit in the rear for some reason. I think these welds quickly changed his mind.

I think that's an example of brazing.

[southbay356]

How do you remove the old braze material ?

I have some fender flares and the outer lip was brazed on when they were contoured for more clearance

dave

[roblav]

With brazing, you have to watch the amount of heat you use. But there is nothing wrong with the structural integrity of properly done braze welds.

21 years ago, I put an early 911 into a guard rail at about 70 MPH. I had previously completely brazed up the entire chassis, including full pan, torsion tube, rockers, etc. Not one single of my welds broke in the accident.

[roblav]

Also, my current formula cars, made in the UK, are braze welded. And I've wrecked those too without a single weld breaking.

[matt13421342]

I think people tend to underestimate the strength of metal joining techniques. Considering you could hang your entire car from a 1-inch weld, even if brazing only gives you half the strength you are still very far in front of the point of accidental separation. Brazing was used for years succesully. That said, even if I knew how to properly braze a joint, the MIG is just so quick and easy ...