Soldering panels together

[DirkRhodie]

So hopefully I dont get my nuts busted for asking.... My question is on a patch panel (it would obviously need a flange around it) why not after tacking patch in then to solder it like they did on the roof panel joint?
My thought is less warpage and zero bodyfiller.... Yes one would need to clean well before paint but would the whole job not turn out better than stitch welding the panels together?

 

[69PHOENIX]

O.K.
The Technique is known as Lead Loading / Wiping and after spending two years at Night Classes trying to learn Panel Beating Many Years Ago, I can only say it ain't easy.
And if it isn't done Right it will Fall Out!
Now if You're a Champion Solderer Good Luck to you.
But with Flexible Stuff like Bolt on Panels I think there's a reason they use Filler. It will Stick & it will Flex with the Paint.
I'm sure there are Better Experts then Myself But it's a Lot of Work to Re-Do if it Fails.
Take a Look at some You-Tube Vids, There are Special Techniques & Steps involved.
Hey, Good Luck Hope it Works for You.
Tony.M
P.S. At some Stage you will need to Sand / Grind the Solder, Make Sure You are Using the Proper Breathing Gear.
A Lung Full of Nicky Dust will make you Crook, But Lead Dust could Possibly Kill You.

 

[DirkRhodie]

O.K.
The Technique is known as Lead Loading / Wiping and after spending two years at Night Classes trying to learn Panel Beating Many Years Ago, I can only say it ain't easy.
And if it isn't done Right it will Fall Out!
Now if You're a Champion Solderer Good Luck to you.
But with Flexible Stuff like Bolt on Panels I think there's a reason they use Filler. It will Stick & it will Flex with the Paint.
I'm sure there are Better Experts then Myself But it's a Lot of Work to Re-Do if it Fails.
Take a Look at some You-Tube Vids, There are Special Techniques & Steps involved.
Hey, Good Luck Hope it Works for You.
Tony.M
P.S. At some Stage you will need to Sand / Grind the Solder, Make Sure You are Using the Proper Breathing Gear.
A Lung Full of Nicky Dust will make you Crook, But Lead Dust could Possibly Kill You.

Correct it requires a certain learning curve, my thought is that @ 90 of the soldering bavk in the day is still holding on today and that it should greatly improve the area for non rusting along the welded areas. As we all know some places are almost impossible to get from the inside to coat against rust and start showing signs all over again.

 

[bigmoparjeff]

On the factory joint, the solder is only being used to fill the depression. The panels are welded together before they are leaded. Lead solder isn't strong enough to bond panels together.

You can bond panels together with the modern structural adhesives. The panels need to overlap and have a fairly tight fit. I'm sure you can find plenty of videos on YouTube about using structural adhesives. Zero chance of warpage when using these. A friend of mine just installed a new roof on a Ramcharger using a combination of welding and adhesive. Welding on the thicker metal in the pillars and adhesive on the thin sheetmetal.

Jeff

 

[DirkRhodie]

On the factory joint, the solder is only being used to fill the depression. The panels are welded together before they are leaded. Lead solder isn't strong enough to bond panels together.

You can bond panels together with the modern structural adhesives. The panels need to overlap and have a fairly tight fit. I'm sure you can find plenty of videos on YouTube about using structural adhesives. Zero chance of warpage when using these. A friend of mine just installed a new roof on a Ramcharger using a combination of welding and adhesive. Welding on the thicker metal in the pillars and adhesive on the thin sheetmetal.

Jeff

Thanks Jeff yip seems 3M has some pretty crazy panel bond, and yes I didn't know about the roof panels been spot welded first.

 

[CBODY67]

There might also be some "weld-thru" sealers and such, too.

 

[Pax2001]

As Tony.M alluded to, there was a reason manufactures went away from lead as a filler. Plastic filler is more cost effective, easier to work and more durable. Lead also has a tendency to encourage rust to the surrounding metal if not applied 100% correctly.
It is usually finished using a body file rather than sanding - for the health risks mentioned. A body file has cutting edges in a flat half moon shape rather than like the teeth of a rasp or steel file and can achieve a very smooth finish with practice.
In either case, preparation is vital.
I would personally recommend a good weld job and then straighten the work out as much as possible and use filler to finish it. (Hot shrinks can take a lot of the deformation out after welding.)
Just my thoughts
Peter

 

[DirkRhodie]

As Tony.M alluded to, there was a reason manufactures went away from lead as a filler. Plastic filler is more cost effective, easier to work and more durable. Lead also has a tendency to encourage rust to the surrounding metal if not applied 100% correctly.
It is usually finished using a body file rather than sanding - for the health risks mentioned. A body file has cutting edges in a flat half moon shape rather than like the teeth of a rasp or steel file and can achieve a very smooth finish with practice.
In either case, preparation is vital.
I would personally recommend a good weld job and then straighten the work out as much as possible and use filler to finish it. (Hot shrinks can take a lot of the deformation out after welding.)
Just my thoughts
Peter

Thanks Peter for your input and much appreciated for everyone else, it was just a out the box thought of mine on the subject, and I agree with all on the various points.

 

[Big_John]

So hopefully I dont get my nuts busted for asking.... My question is on a patch panel (it would obviously need a flange around it) why not after tacking patch in then to solder it like they did on the roof panel joint?
My thought is less warpage and zero bodyfiller.... Yes one would need to clean well before paint but would the whole job not turn out better than stitch welding the panels together?

One thing not mentioned is that solder used for fill has different properties than solder used to hold something together mechanically.

The solder used for fill would be 30/70 and that's the percentage of tin to lead. It's a low melting point with a good range of temperature where the solder remains in a "plastic" stage and you can mold it to shape. Just for comparison, that solder that you find on most guy's hobby bench is 60/40 with a higher melting point, but a much stronger tensile strength.

I have no idea what they use for soldering a tin roof together, but I'll bet it's nearer to the 30/70 alloy as that would be easier to mess with up on a roof.

Depending on where the patch is, a good soldered patch would probably work, but most rust outs that I've seen wouldn't count as being in a good spot for that. On the other hand, these cars were spot welded together, and sometimes not all that well, and they seem to have lasted, so there's that.

I wouldn't do it... FWIW, in the past, repairs were often done with brazing new panels in place. Everyone is aghast when they dig down into an old repair and see the brazed panels, but that was before MIG became a standard body shop tool too. The brazed panels, if done correctly, lasted the usual length of ownership and everyone was happy. MIG changed it. The really good body guys gas welded. Look up "hammer welding" by someone like Gene Winfield if you are really interested, but I'm going off topic.

I'd MIG weld it. Can't beat the strength and you don't have to worry about cleaning up the flux that will rust and destroy your hard work if it's not 100% gone. Plenty of videos on how to do it without warpage and MIG welders can be had for not a lot of $$ these days. Even the cheap ones work well.

 

[DirkRhodie]

One thing not mentioned is that solder used for fill has different properties than solder used to hold something together mechanically.

The solder used for fill would be 30/70 and that's the percentage of tin to lead. It's a low melting point with a good range of temperature where the solder remains in a "plastic" stage and you can mold it to shape. Just for comparison, that solder that you find on most guy's hobby bench is 60/40 with a higher melting point, but a much stronger tensile strength.

I have no idea what they use for soldering a tin roof together, but I'll bet it's nearer to the 30/70 alloy as that would be easier to mess with up on a roof.

Depending on where the patch is, a good soldered patch would probably work, but most rust outs that I've seen wouldn't count as being in a good spot for that. On the other hand, these cars were spot welded together, and sometimes not all that well, and they seem to have lasted, so there's that.

I wouldn't do it... FWIW, in the past, repairs were often done with brazing new panels in place. Everyone is aghast when they dig down into an old repair and see the brazed panels, but that was before MIG became a standard body shop tool too. The brazed panels, if done correctly, lasted the usual length of ownership and everyone was happy. MIG changed it. The really good body guys gas welded. Look up "hammer welding" by someone like Gene Winfield if you are really interested, but I'm going off topic.

I'd MIG weld it. Can't beat the strength and you don't have to worry about cleaning up the flux that will rust and destroy your hard work if it's not 100% gone. Plenty of videos on how to do it without warpage and MIG welders can be had for not a lot of $$ these days. Even the cheap ones work well.

Thanks a mil for your input.