What sheet metal guage should I use on a 1970 Pontiac Firebird ?

Question

I am going to fabricate a patch panel, and would like to know if I should use 16 gauge or 18 gauge. The patch will go on the lower rear windshield near the trunk lid.

Answer 1

You should use 22 gauge which is the standard guage for most vehicles from the 1970's and up. Thicker gauge than that would make it very difficult to bend in anyway to the form you need and would be too thick compared to the metal already on the car making it hard to grind flat to fill over and make level to the area. You will end up grinding the welds away before you got 16 or 18 guage to be level and smooth enough. Plus heating up the panel your welding it too much and warping it. Steel gauge is similar to wire gauge. the lower the number the thicker it is.

You can purchase 22 gauge sheet metal at most auto parts stores and autobody paint supply stores also carry it.

They also sell panel bond adhessive which can be used in place of welding the patch if you dont have a welder. Just remember that it comes with mixing tips that  you will also need to buy. It drys very quickly so be sure you have the panel fitting just the way you need it before applying it to the back of the patch.

Good luck!