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Anyone have bubbles or paint problems with original factory Lead Work? Just found a line of thought by some shops that won't guaranty paint / body work over any lead work, original or new.

On my 53' Coupe now stripped all the original and re-paint work was fine in the leaded areas, wondering if techniques, lead alloy or flux used at the factory was different, maybe a new / modern problem?

Any thoughts much appreciated...

John Willhoit uses some kind of metal filler on all his high end restorations. I will see if I can find the link. viewtopic.php?f=13&t=42934&start=15 I may be mistaken about Willhoit using lead. Maybe some other product. It might be wise to contact John Willhoit, Steve Hogue Enterprises and others.

Yes, saw a pretty fresh restoration of a stunning Speedster recently with the bubbles you are talking about. I recall lengthy discussions between antagonist Miamiair (advocating use of lead) and I would have sworn John Wilhoit did not advocate the use of lead. I think a lot of shops are using products such as All-Metal to avoid problems such as those shown in the photo.

Steve You may be correct. From the link I attached I assumed lead but may be another product as you describe. I edited my comment for clarity.

I have used body solder from Eastwood on four cars over the past 20 years. If done properly (making sure all acid from tinning is removed before applying the solder), there should be no bubbling. It is a lost art and one I learned from an old auto guy who passed away many years ago.

+1 re Paul Vantols reply

"All metal" is really filler. But so is lead. Plastic fillers used correctly will last as long as lead. Those who use lead do it for authenticity reasons I suppose. It's best to remove it from what I've read.

Lead filler, in areas where the factory used it, is acceptable as long as it's done right. The paint issues down the line likely stem from residual acid in the initial tinning compound, since the lead/tin alloy is neutral in pH. The key to avoiding problems is to fully neutralize the tinned surface before applying the lead.

If you look at videos of some of the old hot rod guys, you will see efforts ranging from washing the tinned surface with a wet rag to applying a baking soda/water mixture. The goal is to get rid of the acid in the tinning compound.

My routine was picked up from a fellow from Europe a number of years ago; I have done a number of cars with very good results regarding paint many years out.
1) After tinning the area using Eastwood's paste and a torch, I wash off the brown residue with water and a paper towel.
2) Then I apply a solution of powdered dishwashing-machine detergent and water which has a pH of 13.5+ with a brush and let it sit for 20-30 minutes. Afterwards, wash it off with a spray bottle of water and check the pH of the surface with pH strips used to test pool water. If it's not in the pH 7+ range (which it nearly alway is), repeat the process. When you're happy with the results, let it dry throughly before applying the lead and filing. A good indication of how well you have neutralized the acid is the final pH of the surface as well as not seeing rust appearing on the surrounding bare metal which was not tinned.

3) If you have any concerns that you might not have neutralized the tinning in any area, paint the lead with the solution of dishwashing detergent and water again after you have filed and shaped it. This has the advantage of removing any traces of tallow used in the lead application as well. Wash with water and allow to dry.

I also use Metal to Metal filler in places, sometimes over the lead to fill small imperfections or add a mm of thickness when I don't want to repeat the leading process. This filler tends shrink less than regular filler, but is somewhat more difficult to sand.

So, there is a place for both methods if you have the time and expertise to apply them properly.

Good point about lead not shrinking like plastic, but I found that if you allow the filler to cure for a couple months before doing your final sanding you can avoid shrinking issues. Same with the sandable primers. I let them cure and shrink for a month minimum before doing a final sanding. The longer the better as long as you have epoxy under and keep it dry and oils away. Nothing worse then getting a car back from paint that looks great and then a few weeks later seeing all the sanding scratches from the shrinking sub surface.

Bob Cannon wrote: I also use Metal to Metal filler in places, sometimes over the lead to fill small imperfections or add a mm of thickness when I don't want to repeat the leading process. This filler tends shrink less than regular filler, but is somewhat more difficult to sand.

Metal to metal is definitely harder to sand, and doesn't feather as well. My 62 and another car we are working on have metal to metal in the factory leaded areas. Harder to work than standard fiberglass filler, but definitely stronger and easier than lead to apply.

looks like poor body work prep to me.

Recommended cleaner of leaded areas before painting is a solution of equal parts ammonia, alcohol and water. Don't ask me the chemical reasons, but this is what paint manufacturers are recommending now and it seems to work.

Thanks Jim.

Be careful sanding and grinding lead.
I worked in the sheet metal trade for 40 years and seen some health issues form its use.
The factory lead in my T-1 was rusted under the lead.