Body solder

[stag36587]

All, I'm about to fill the body seam above the rear wheel arch lip of my saloon which was originally lead-loaded. By being careful with my welder I only need to fill a very small area. I could order a body solder kit but just wondered if others have used anything different?

[beero]

There are many videos on youtube about lead loading. Looks difficult!

[chickenjohn]

I've done quite a bit of lead loading/ body solder work and it is much easier than people make out. Frost sell a starter kit, you can use an ordinary blow torch, although oxy acetylene heats the solder up more quickly.

Once you've tinned and wiped the area to be leaded, the biggest danger is heating the body solder too much and having it melt and sag and drop on the floor before you can spread it with a paddle. Put a wooden board below where you are working so you can catch any falling solder. This can then be melted in a bit of angle iron to get it back to being a usable solder stick again. Can then try again.

[twincamman]

I've never tried lead loading, but I read somewhere that using a heat gun (as used for stripping paint) makes the heat more controllable. Many of these heat guns come with 2 temp settings and one of them is suitable for soldering/lead loading.

[stag36587]

Thanks I'll definitely give it a go!

[Alec]

Hello Stag,

I don't know how much the kit costs but it's worth checking your local electrical or plumbers merchants for plumbing solder sticks, (60\40 lead\tin) and solder paste, which you use for tinning?

Alec

[dunketh]

Make sure you post your findings. Always fancied this as an alternative to modern body filler though I'm not sure if its worth the effort given how good and easily workable filler is these days.

[stag36587]

That's what I was wondering particularly as there is now good quality metal-based filler on the market.

[Alec]

Hello Stag,

in my view, metal based filler is no better than conventional filler, in this application. Where lead is superior is in it's grip on the steel, it is not porous and is more flexible. It also sets quicker so no hanging around waiting for it to dry. The drawback to it is that you can't use power tools to remove any excess.

Alec

[chickenjohn]

Alec :-

"in my view, metal based filler is no better than conventional filler, in this application. Where lead is superior is in it's grip on the steel, it is not porous and is more flexible. It also sets quicker so no hanging around waiting for it to dry. The drawback to it is that you can't use power tools to remove any excess."

That is my view as well.

Lead body solder will never crack if you slam the door too hard too many times for example! and will add strength to the steel panels. You can't beat a metal repair IMHO. Solder applied to a strip of sheet steel has been tested to destruction by bending it in a vice and the steel cracked before the solder!

A few other comments, I have heard of folks using 60/40 although the preferred is 70/30 lead/tin solder as it has the widest temperature window for the "pasty" stage, i.e. between solid and molten. You need to get the solder "pasty" and can then spread it like butter with a tallow dipped paddle. Minimises the body filing and hand sanding needed. By "body filing" I mean using a coarse steel body file to shape the solder to the panel after application. The body file can be set to flat, concave or convex to suit the panel.

I would also prefer using a blow torch over a heat gun to soften the solder as the heat from the blow torch is more concentrated and therefore less likely to warp the panel. Oxy acetylele with a no2 nozzle is better still.