P. Leading the Roof / Sail Panel Seam
Post date: Sep 29, 2015 5:50:55 PM
The joint between the roof and sail panel is a seam that sees quite a bit of stress and the factory used lead to fill the valley as it provided a flexible filler while also adhering very well to the steel panels. With the paint cleaned off this area, it is hard to tell just where the lead begins and the steel ends. When you look at it from different angles you can see it rather easily. Before the quarter panel was cut off, the lead needed to be removed because the cut line was going to be near the factory welds of the quarter panel to the B-pillar structure. To remove the lead you simply use a propane torch and a wire brush. It comes out without much effort, but be careful not to overheat the steel as it can warp the panel. Once you get the majority of the lead out you can then go over the entire area with a wire wheel to clean it good.
The old quarter panel was cut off just below the roof edge and the new quarter was butt welded to the part that remained of the original quarter panel.
The area was then wire wheeled and scuffed with 80 grit to provide a clean surface for the tinning compound. The area needs to be completely free of organic material, so take plenty of time in this process.
You then need to tin the area that you plan to lead, here you want to put tinning compound on an area that will exceed the area that you plan to lead. With you torch heat up the tinning compound until it melts and turns shiny. Then wipe the area with a clean rag (cotton) so that it is shiny. You will want to remove the brown material that is developed in the tinning compound while it is molten. Once tinned, use 70%-30% solder (from Johnson Manufacturing) to fill the seams. You first apply it to the panel - mound it up and once it has solidified come back and reheat to paddle it in.
Next step is to use a body file to level the lead and then skim with filler if needed. Beware of lead dust when you are sanding and filing - it is very dangerous and will harm you. Always were the proper respirator and have good air flow at all times with working the leaded area.
Here are the seams after filing the lead and etch priming. Next step in media blasting the truck and various parts and prime with 2K primer and then doing the finishing bodywork and blocking can begin!
And here are the sail panel areas after paint, cut and buff