frame help

[Deleted User]

I need to patch some holes in the frame of my 52HH I need to know the thickness of the metal to use?

53jetman

Ken U-Tx - It would be nice if someone here does know those specifics, that it could be included here for those of us that will be at some time or another getting into frame reconstruction. I know that when I rebuilt the perimeter rails on my Jet sedan, if I had known exactly what gage of steel was used at the factory, it would have made life a bit easier !

[Deleted User]

I dont believe I would be that particular . The steel they used was extra strong because of the unibody . And the fact they were in new unfamiliar terrain so they over built. Modern mild plate steel of same thickness wouldn't be as strong .

Roger

RL Chilton

Otto54-

To answer your question, due to the varying thicknesses of various portions of the frame and due to the slight "flattening" you get on some stamped parts, it's best to use a pair of calipers on surrounding metal and match it up as close as you can with the appropriate gauge metal. You'll find that some areas work out to 19-gauge (floor pans, for example), which is no longer made, but enough searching through a stack of 18- & 20-gauge with a pair of calipers and you can actually get very close to a 19, or any other odd number that comes up.

bent metal

I have been asked this questions many times, and I'm sure it will come up again. The above answers are correct, in my opinion. As Ken U-TX, and Russell say, you should always measure where you are making a patch and match the surrounding metal. ...Why? Why not use thicker metal? Isn't thicker metal better? No, it's not. Because when you weld in the patch the expansion and contraction of the weld is going to be different on different thicknesses of metal. One side will be stronger than the other. More likely to crack right next to the weld. You want them to be the same thickness, become one again. Also, you won't be able to planish (hammer smooth) the metal as good if they are not the same thickness. I know that from lessons learned a long time ago, in areas more noticable than a frame rail.

Also, 19 gage (the metal suppliers spell it that way Russell , I don't know why. No offense, I know you were trying to nicely correct me. ) is available, and at different alloys. But generally, what you said is right. A local supplier will say they only have the even numbers, and they also tell me the odd numbers are not made. But it's not true. You just have to talk to someone higher up than the ding-bat at the counter. Or like you say, and I do too, take something with you to measure the metal, in the yard. Because sometimes what they "say" is a certain gage, is not what the department of weights and measures has specified as that gage/thickness! It's a rip off, I think, but the way it is. ...We won't even get into ductile or tensile strength for shaping of metal. Sometimes they give you metal that is soft, sometimes metal that is from China, and brittle. Imported stuff is unpredicatable. You need to be able to identify that crap in the yard. If you have to shape the brittle stuff a lot, your going to have big problems later. Ask me how I learned that lesson.

RL Chilton

bent-
I would never try to correct you. I actually didn't know that (about the spelling). Or if I used to, I had forgotten.

bent metal

Haha, okay Russell. I noticed in another thread you kept spelling it gauge, and I kept spelling it gage. I'm sure it means the same thing though. But for some reason the metal suppliers and reference books spell it 'gage'. ...I don't know why, nor does it make a difference either way.

I'll let you guys in on a metal shaping secret. When you get to the yard, and find the thickness you want. Grab the corner, about three inches in and try and bend it up with your bare hand. If it goes it will be good for shaping. If it doesn't it's too hard. Good for folding and light shaping. But it will fight you all the way if you plan on making anything with shape, like a door panel or fender or something. Especially when you go to bend the edges/flanges. I learned that the hard way. I've even got metal that was so brittle/hard that it cracked when I bent it on my brake! I took that piece back to my supplier and he quickly took the skirt that had cracked from my hand and with an embarrassed look on his face. He appologized and delivered a new sheet the next day to my house, no charge. He must have been aware of the problem, a bad shippment from China or some place.

So I always check the metal first. Just because they say it's a certain alloy or gage doesn't make it true. This imported stuff doesn't follow spec like US or Canada made stuff does.

RL Chilton

It is my understanding that if it breaks (cracks, too brittle) when you try to work it, it is because the carbon content is too high. Causes it to lose tensile strength. Y'all ever tried to work a fender on a modern day foreign job? You're lucky if your body hammer doesn't sling back off of it and land in your face. When it comes to working the metal, I am beginning to believe there is nothing like soft, malleable, OLD tin.