[ponchjoe]

Hi guys

What is the correct way to weld up holes on a trunk lid where the PONTIAC letter were? I want to make sure the body guy I'm going to use is thinking the same way.

Thanks

[400 4spd.]

This what I would would probably do to keep distortion to a minimum.
The holes pass through two panels, correct? If so,
Clean both sides of the area to weld down to bare steel. Clean paint and corrosion from all of the holes with a tiny (1/8") round file, because that is where the weld needs to melt in. Chain saw files work great for this. Also have the surrounding surfaces on both sides free of paint, etc.
The holes go through the outer skin and the inner structure. The inner structure is less prone to warpage for a couple of reasons. By the time you have the holes welded the two layers will become fused at those welds. SO......
Have an air hose handy with a blower attached.
With the trunk lid laying inside facing up, place piece of clean and flat copper sheet against the outer skin, covering one of the holes. A piece of copper tubing can be split and flattened or just hammered flat. You can clamp it or use large magnets to keep it firmly in place. Working on the inside of the trunk lid, mig weld into the exposed hole along the edges, using the copper as a back stop for the wire. Weld only for a couple of seconds and then immediately blow a good stream of air onto the copper plate which will transfer the cooling temp into the trunk lid skin. Do this for at least 10-15 seconds and then complete the weld from inside. Rapidly air cool again. DO NOT use a wet rag.

If your guy decides to weld the holes up from the outside, most likely the surrounding area will raise with the expansion the outer skin. This happens during welding and what you end up with is a weld plug that is too thick and holding the panel up. You can forget tapping it down, because you now have fused the inner panel to the outer. Move over several holes and repeat. By the time you finish you may find a crevice or two in the outer side of the welds. Those can be quickly migged up and cooled, then filed or ground flush.

If you have a single layer that the holes pass through, (blind on the inside) it will have to be done from the outside. Because it's not fused to an inner layer, the metal is going to very prone to warping, so again, clean area, short weld time (maybe half a hole first) air to keep it cool.

[ponchjoe]

It is two panels, and thank you for the detailed response.