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Brianstick
01-07-2009, 07:13 PM
Does anybody know what the sheetmetal thickness is on the new cars? I had a '74 ford torino that I know was 18 guage but what are they now 20 or 22 maybe?

whateg0
01-07-2009, 09:01 PM
It varies from car to car and mfr to mfr. You should just mic it if you have to match it exactly.

Dave

Thurman
01-26-2009, 09:27 PM
Brianstick, with all due respect I find it hard to believe that sheet metal from a 1974 American made automobile has 18 ga. (.0478") sheet metal. The reason I say this is that I have rebuilt two older vehicles, a '55 Chevy and a '67 El Camino and have found the sheet metal to be in the 22 ga. (.0299") and 24 ga. (.0239") range, depending on the panel. IF you have indeed found auto sheet metal in the 18 ga. range that's great. I do remember the '74 Ford's and they were indeed battle tanks on wheels. As far as the newer cars, I believe they are in the 24 ga.-26 ga. (.0179") range. I spend time at a friends body shop and have heard him and his employees say it's almost impossible to weld today's sheet metal because it's so thin. Besides that, in today's world it's parts changing, not repairing. Thanks, David

Hotfoot
01-26-2009, 10:55 PM
The modern steel in auto bodies is also "High Strength", besides being thinner...it just doesn't work like the old stuff in terms or hammering and beating dents out. I find it more "crinkly" than mallable, I usually get it as good as I can and skim some filler over the area. I don't try to patch newer panels, just replace them.

This all comes out from a couple directions, lighter weight (fuel mileage), and the higher strength is required because the entire skin of the car is now a dynamic system, rather than perching a separate body on top of a frame that carries all the suspension and drive train loads....and its now engineered with big crashes in mind to sacrifice the body to protect the inhabitants.

The difficulty welding it is why all body shops now use panel adhesives and fillers to "patch" areas...which work great!:)

kenc
01-27-2009, 11:13 AM
Brianstick, with all due respect I find it hard to believe that sheet metal from a 1974 American made automobile has 18 ga. (.0478") sheet metal. The reason I say this is that I have rebuilt two older vehicles, a '55 Chevy and a '67 El Camino and have found the sheet metal to be in the 22 ga. (.0299") and 24 ga. (.0239") range, depending on the panel.

Wow, that's hard to imagine.
The sheetmetal on both my 56 and 57 Chevy is around .040 or 19ga.
22 to 24 ga is incredibly thin - perhaps the new HSLA steel used on modern cars can be that thin, but not good old cold rolled steel on a pre 80's vehicle.

whateg0
01-27-2009, 01:51 PM
IIRC, the floor of my 47 PU is about 17 ga and the body was a little thinner. I know that it's thinner than the 18 ga that I bought for the floor. Probably about 20, but I'd have to measure it again to be sure.

Dave

Aerometalworker
01-28-2009, 06:06 PM
Yeah I would just measure it. I have seen anything from .018 to .047 on vehicles from about 1920-1980, so its hard to guess for your application. Most of the HSS you find in modern cars is in the structure, not the outer panels. Fenders, door skins, trunks, hoods are rarely anything special. Now the subframe is many times HSS nowdays. Trouble is the manufacturers are hard to get information out of. These shops that have gotten rich and fat off of parts swapping and squirting paint may have fun when we get more and more aluminum in the bodies. I heard a story of a shop that got in a rear ended BMW, and tried to replace the trunk lid....to the tune of many thousands of dollars. The insurance company said " your going to repair that" as the factory flat rate for repairing the part was less then a new part...or so im told. Well this gold 5 star shop...had no idea how to work on aluminum sheet......so they had to give it to the local aircraft sheet metal worker. Hmm maybe there will be jobs for us aluminum guys in the future....hmmm.
-Aaron

kenc
01-29-2009, 09:36 PM
Fenders, door skins, trunks, hoods are rarely anything special.

I think you'll find all of the exterior panels are HSLA steel.

Aerometalworker
01-29-2009, 11:11 PM
I think you'll find all of the exterior panels are HSLA steel.

Maybe it depends by vehicle, none of the post 1995 vehicles I have worked on have had HSLA steels in those parts. And in reality it makes sense, trunks, hoods and door skins arent structural in the sense we think of them. One of my co-workers was an engineer from Ford , and when he left in 2005 the only plase high strength steels were used were in the "frame" of the car, not the cosmetic skins we see.
-Aaron

kenc
01-30-2009, 11:16 AM
Not structural, that's true, but same strength at thinner gauge than CRS.
Weight is king for the auto companies trying to meet CAFE standards.

Aerometalworker
01-30-2009, 12:18 PM
Not structural, that's true, but same strength at thinner gauge than CRS.
Weight is king for the auto companies trying to meet CAFE standards.

Yeah.....tell me about those CAFE standards.....what a joke. What amazed me was when I visited northern LA. For a state that whines so much about fuel economy, and loves to point the finger at the auto companies, there sure are a lot of big SUV type vehicles on the road over there, normally driven by a soccer mom type person as it would seem. If everyone was so concerned over there.....I would think they would all buy the fuel effecient cars that have been on the market for about 40 years now. Oh yeah and now pile on safety and crash standards, equipment standards. Basicly state government is laying out the design for the vehicle and then complains when its not as effecient as they would like, or costs too much. Ive got an idea, let engineers desigh vehicles, and let government worry about taxing your drinking water.