Hello all, this is a question for you tub fixer uppers / rebuilders.
I called around for some sheet metal today and I'm fixin' to get two 4x8 sheets of steel. But I have a question regarding gauges (thickness):

I know that most of the tubs were made with stuff close to 18 gauge, but that is thick stuff, and I'm agonizing whether I should go with 20 gauge to make life easier. Which thickness should I get?

I need to make front floors, and at least one whole side of the tub, the rear panels (tail light areas) wheel house sides, and the step up piece between floors.
(I'm using pickup bed floor metal I scavenged for my rear floor...it's nicely corrugated)

Would 20 gauge just be too wimpy? I am going to make hat channels out of 1x2 square tubing by the way.

If you have any wisdom, been there / done that comments, I'd appreciate it.

I agree with 1955CJ-5.  20 gauge could be problematic.  I chose 16 gauge for my repairs.  It harder to cut and bend, but easier to weld without oil canning and warping.

I measured steel thickness on 3 different tubs in 3 similar spots.  These 9 measurements averaged .0518".

16 gauge is suppose to be .625" ish
18 gauge is suppose to be .049" ish

Coincidently, the sheet of 16 gauge steel I used, measured out to be .0570".  A little thinner than .0625".

Hawk

To make the curves for the rear panels I bought a 6" or 8" diameter(I forget, so you need to measure...) length of PVC, then filled it with post hole concrete, because it flexed to much and that was my form....I'll look for a picture....

Found some...

I agree that 20 would be too thin.

I used a couple sheets that have been around my garage for years.  One was .050,  and one was .057. . .  unfortunately for me,   by the time I got to doing the passenger rear quarter,  all I had left was the .057.  For me,  that was a PAIN to bend into shape. 

My floor patches are .075    . . again, because I had a bunch of it.   No oil-can in those floors.   

Tonite I just cut out some of front fender,  I measured .038 in an unrusted section.