is brazing patch panels in bad ?

[SoCal Dave]

Hi

I have an old retired body guy that offered to fix some rust holes in my bus floor and rockers,

He plans on brazing in the patch panels .

anything wrong with that ?

he says thats what he did for years and what he is comfortable doing ,

What do you think ?

[CUSHE63]

Brazing went out with the 70's. Don't do it, it just sucks. Mig or tig is the way to go. Tell him to get with the times.

Just my 2 cents, Steve

[Gary]

[TheTominator]

There was a time when a torch and a metal coat hanger was the way to go. Sometimes you would spring for welding rods, if you had the cash. Todays methods are better mainly because they heat the surrounding areas much less. That is very important with todays very thin metal panels. Heat deforms metal by causing it too swell. However, this method of attaching metal to metal is effective. Bodymen of that era knew how to shrink metal with heat and a hammer and were more skilled at working metal. The average body guy today can patch metal, but he will use bondo over his patch. In olden times, they patched and then melted lead over the patch and shaped it, no bondo because it didn't exist. I suspect your guy knows what he is doing and i would welcome his help. Bondo sticks to a braze as well as it does to anything else. Good luck, Tom.
_________________
"A foolish faith in authority is the worst enemy of truth" Albert Einstein - 1901

If I can't curse, I can't fix it.
71 Bus
78 HD FXS Lowrider 1200cc
An Oldsmobile for crying out loud.

[tchaika]

There is a common perception that old fashioned panel beaters were better and more skilled. I think there are exceptions.
In theory there is nothing wrong with brazing for many applications. In practise it was done a lot by people who were not competent to make a nice fitting patch and butt weld it in and this has given it a bad reputation. With brazing you can put lots of filler rod in to make up for sloppier fit-up of panels. I guess these people now buy a cheap mig welder and a bucket of filler. It leaves you with a lap weld with dissimilar metal and possibly flux in it. I have seen and read about many horrors of brazing on car bodies due to rust.

Ask the guy why he wants to braze as opposed to oxy weld, given that both processes require the same equipment. If he has a good reason, then he knows more about it than I do.

Also, you will have to get *all* the flux out. Otherwise you will get serious paint and rust problems. Maybe it is the combination of dissimilar metals (galvanic corrosion) magnified by salt/dirt/rust/water/bad preparation.

[winston the browndog]

Brazing is a type of soldering. You are only applying brass rod ,via flux which is cleaning the surface, to the top surface of the steel and not getting any penetration into the substrate. Where as in welding IE mig , tig ,etc.
you are melting the panels together and making one soild piece . Hopefully

[John Kelly]

A properly welded joint is superior to a brazed joint. Brazing is more like a very strong glue. You will not want to repair a any future damage that has been brazed. It makes a big mess of the metal.

If you are comfortable with the guy, and this is what you can afford, nothing wrong with it if done right.... especially if you are not building a concours car, but a daily driver.

Welding and smoothing the metal afterwards takes some commitment and effort to learn. You will get some shrinkage (thickening) in the metal whether welding or brazing.

John www.ghiaspecialties.com
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[Scott Faivre]

Paint and primer doesn't stick to brass very well. I wouldn't recommend it. Now if you're planning on Chroming these areas, go for it! Chrome loves Brass!

Mig weld it in.

Scott Faivre
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66 Sedan & 64 Convertible
64 Vert Resto Gallery

[TheTominator]

old retired body guy that "offered to fix some rust holes" in my bus floor and rockers,

He plans on brazing in the patch panels .

anything wrong with that ?

he says thats what he did for years and what "he is comfortable doing ,"

A).He retired from the profession, indicates lots of experience and compentcy.
B). That's what he is comfortable with, I.E. skilled at.
C). "It's for free?!!!!, It's for me.
_________________
"A foolish faith in authority is the worst enemy of truth" Albert Einstein - 1901

If I can't curse, I can't fix it.
71 Bus
78 HD FXS Lowrider 1200cc
An Oldsmobile for crying out loud.

[smuenchrath]

Hopefully when its all said and done, the brazing doesn't look like my car....

there was over an inch of bondo on top of that mess....

[Ipaintem]

Body filller will not stick to brass. So all the time you spend brazing in the panels will will be fruitless 6 months from now when your filler starts popping off. I learned from an oldtimer like that to do paint and body work. A lot of the principals are the same when comparing old to new but the products and techniques are WAY different. I know its free but when you have to redo the body work and buy more paint and repaint it or pay someone to repaint it, have you really saved anything?

[ivsamhell]

theres brazed joints from the factory. but i'd stick with welding for repairs.

[jaymonkey]

[Ipaintem]

O.K., then do it!

[TheTominator]

That's what I'm talking about! All you naysayers to brazing repairs, begone. To hear you guys tell it, all the bodyshops in the land spent the first 3 days of every week redoing what they did the week before. I don't care what whoever told you when you were learning. Brazing was THE way to do it and Somebody tell me again why bondo can't or won't stick to a braze that was hit with 80 grit. I absolutely agree that todays welding methods are better. But, brazing worked and still will, and a guy who retired from a career using that method and is willing to help you for free? You gotta be rich or just plain damn crazy to turn that down. Unless of course one of these know it alls shows up on your doorstep and offers to do the job for free with their method. Personally, I would consider their years of experience, before I would toss the retired guy aside. After all, he has nothing to prove. He already RETIRED as a professional.
_________________
"A foolish faith in authority is the worst enemy of truth" Albert Einstein - 1901

If I can't curse, I can't fix it.
71 Bus
78 HD FXS Lowrider 1200cc
An Oldsmobile for crying out loud.

[Ipaintem]

Old timers also fixed rust holes with chicken wire bondo and newspapers. This dosent mean we should still do it. Our cars are unibody cars. Each and every weld is relied upon for structural integrity. If you braze in a patch panel it will not be as strong as it should be. Braze in a few panels in key areas and watch them fail when the car gets driven and put through everyday twist and flexing. If you want to braze in panels that is perfectly fine with me. Just remember how soft brass is and think how these welds would hold up in a accedent then remember that you wife and children will be riding in this car. Brass would and did work fine on fixing a patch panel on a 67 Chevelle fender. It didnt have to support anything but itself. This is my profession now. THis is what puts food on my table and a roof over my head and has for the past 13 years. I have PPG and I-Car certificates as long as your car. I think its great that this guy is willing to help out with the resto for free. But if you have to go back in a year and dig out everything that was fixed the first time then repaint it , how much did you REALLY save. You dont have to take any advice on this forum, you can do as you darn well please. You can fix your car however you want too. Just think about this, If brazing was so good, why arnt we still doing it today in reputable body shops?

[tchaika]

I got some free bodywork from an 'expert' once. When my car failed safety inspection, I paid extra to rip it out and put it right. Thats why I say hmph to free body work. Just my personal experience.

Here is a quote from The Key to Metal Bumping, a classic of bodywork that everyone interested should read. eastwood co. sells it. It was written in an era when cars were body-on-chassis, but I think that makes this advice even more relevant:

"It is not practical to braze a fender flange or any other panel
subject to vibration from road shock. If the braze itself does
not break, it will fail because the bronze only adheres to the
steel instead of fusing with it and the adhesion later lets
go under vibration. Once a place has been brazed, it can never
be welded. If the braze fails, it can only be rebrazed; other-
wise the entire brazed area must be cut out and a patch
welded in its place.
However, where there is no danger of vibration and it is
better not to heat the metal to welding temperature, a braze may be preferable and may stand up."


The question stands - why, given the same equipment is required, would you braze instead of butt/rosette weld? The only reasons I can think of are to save time, save effort in making patches line up nicely, and lack of skill. I'd still like to hear if this old dude has a response to that, I'm keeping an open mind still just in case.

[jaymonkey]

[Ipaintem]

Your right. If you fix it right there is no reason you will have to do it agian in a year. If you put the car back together the way the factory did then it will be fine. If the factory welded the car together then it should be repaired that way. I nor have any of my co-workers seen a car that was held together with brass. In todays automotive industry brazing is NOT accepted as a means of repair.

[TheTominator]

Brazing Provides Leak-Free Passage For Vehicle Fuel.

Application:

Fuel senders used in vehicles manufactured by Ford Motor Company. Ford Motor Company relies on brazing in several phases of vehicle manufacture. In the assembly of its fuel pump systems, brazing helps provide a leak free route for gasoline to be transported to the engine. Specifically, brazing is used to construct the fuel sender, a part that mounts directly onto a vehicle’s gas tank. With a fuel pump attached to it, the fuel sender pulls gas out of the tank and sends it through tubes to the fuel injection system. In the manufacture of the fuel sender, two stainless steel arched tubes are brazed through a round stainless flange. The tubes fit neatly between the two existing holes in the flange. An operator manually snaps a C-shaped arc of filler metal, (Lucas-Milhaupt’s CDA-521), into the gap between each tube and the flange. The parts are then placed on a belt and sent through an oxygen-free, controlled-atmosphere furnace. The absence of oxygen eliminates the need for flux or cleaning, and the brazed parts emerge shiny and clean. Following this rapid metal joining process, each fuel sender is 100% leak tested.
_________________
"A foolish faith in authority is the worst enemy of truth" Albert Einstein - 1901

If I can't curse, I can't fix it.
71 Bus
78 HD FXS Lowrider 1200cc
An Oldsmobile for crying out loud.