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Opel Sheet metal thicknesses

6687 Views 22 Replies 10 Participants Last post by  opelspyder
Opel Sheet metal

Need help on correct information, what is the gauge of sheet metal for the floorboard metal and outside body- is it 22gauge or 24guage-or am I wrong on both??? Any info is greatly needed
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Floorboards are .078 thick and outer body is .035, both in inch.
The number of .078" (2mm), are you sure that this is for floorboards? I would assume that only "frame" parts have that thickness. Or maybe I just misunderstand the word "floorboard"...

I just put the calipers to it again, that is the thickness.
sheet metal

Floorboards would be 14 gauge and 22 gauge for body.
That sounds correct.. the frame rails, and jackpoints I have gotten from Germany are in the 14 guage range. The Sheetmetal for the body and other areas is about 22ga or so, thats what I make the battery box kits out of.

When I rebuilt the floor on my GT I used 16 guage. The 16 guage was substantially heavier than the original. I used the same steel for the inner rockers as well. The Mantas may have been heavier, but the GT's were made out of very light weight material.
I was using a pair of digital calipers on a removed floorboard, for the body I checked a rear panel the same way.

Okay-14 guage sounds too thick-for jacking points and other structure rails-it sounds right. If one person used 16 guage because it was thicker-then it couldn't be 14guage. I need the thickness of the floorboard panel-I think it is 22guage-will get home and measure myself to get a good guess. Just thought I would buy the metal first.
Honest, no kidding, checked them twice in several areas. I even checked the calipers on a guage block. I have a pair of unrusted floorboards that I'm looking for a box for. They were cut from a 72, I also have a load of sheetmetal body panels. I wasn't guessing, just measuring things for you. If I'm going to post an answer I do my best to be accurate.

fter measuring the floor pans on the &2 GT I have on the rotisserie-the floor pans measure .035 with a digital caliper-no the outside rocker panels appear to be a 16-14 guage metal-but the actual metal panels for the floors with drain plugs measure at the .035. Make sure those haven't been replaced once before. 14 guage sounded thick-there are some sheet metal parts that are the 14 guage. I will go with the 22guage for the floor boards-and get some 14 for the rockers
Ok, I'm done measuring. Yes they are original, I removed them myself.


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22ga. is correct. You get any higher ga. and it becomes very diffecult to work with (shaping). I hope your just patching the rockers, otherwise your going to need a brake to bend the 14ga.
i had a floor pan that matched up with daves numbers. was from a 70 GT.
I did extensive work on the floor and inner rockers of my 70 GT last a year ago. I agree with the .035. I was welding 16 guage (measured at .062) against the original floor panels and continually fought the problem of popping through the original material. The original steel that I was welding to, had OEM paint on it and was without rust. Once sections were cut out, I could easily bend them with my bare hands. The 16 guage required a homemade break or a hammer and vice. 16 guage is amazingly rigid.
I wonder if there were differences in construction? I also welded in 16g sheet metal on both drivers and passenger floors on my 72 GT. The existing floor was fairly easy to rip out due to all the rust, but even unrusted areas seemed thinner than 16g. At one point, I almost scrapped the 16g thinking it was overkill, as 18g would've been easier to shape.
Opel Sheetmetal

Try measuring from the drain holes of the floor pan and see if you get the same measurement-the rockers that are welded right to the floor pans are 14guage-but looks like actual floor pans are .035
The measurements were taken at several locations. The rocker panels are in the shed and not measured. As I stated before this was from a 72 with no rust. The floorboards were removed from Opelgtmaster3's (Aarons) black car. Vin #772785687. I posted the picture with the calipers attached to what is the back edge. Single layer thick not on a weld just a flat section. I'm not trying to argue, the question was asked of thickness. Having a good pair cut from an unrusted car and a pair of calipers handy, I figured I'd measure them for you. I kinda got the impression from the question of how thick they were, that this is what you wanted. I don't know if anybody else has a pair of just floorboards laying about. Then again seems the pieces Charles imports for the Mantas are the same thickness. Hum, go figure.
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Sorry, Nobody, I wasn't suggesting your measurements were wrong or that you had made a mistake. I was just sharing my experiences with floorboard replacement. Which I will admit, I didn't take any thickness measurements!
No problem, I just have a bunch of GT body parts so it's easy for me to check them. I may have measured a small amount of undercoating but not much. On this one the floor boards are the same thickness as the seat rails. If Opel did them in different guages I can't say. I just measured what was in the house for thickness.
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