Front frame repair

[hogie]

The foam does suck.....it seems like break parts cleaner softens it a bit though. I have already spent 3 months screwing with the rest of the car, what is some more time?

[Seppi72]

Because the foam is cross-linked polyurethane (PUR), solvents will, at best, only be able to swell it; at which point you could try scraping it off with a chisel if you have the leverage to do so. The only other option is to burn it out with a torch. You'll get a lot of char because the PUR is based on aromatic ring structures and that's what aromatics do in the initial stages of oxidation (burning). However, that char will eventually oxidize or, when it's cooled, you can scrape or wire brush it off.

Ideally, such burn outs should be done outdoors. If that isn't possible, have good ventilation going; such as a box fan blowing fresh air at your face and another one blowing fumes out the door. If you can smell the burning PUR, your ventilation is inadequate. Stop and fix things.

Also, have an ABC-rated fire extinguisher (or two) handy - just in case. Because the foam is inside a metal structure, I don't believe that burning would be located anywhere other than on the exposed surface because enough oxygen would not be able to get to the hot zone from any other direction. But never say never.:stupid: Also, be sure that combustible materials (grease, oil, plastics, etc.) are not in contact with the other side of any metal surface that's being heated. Of course, any paint on the metal will be "toast".

BTW, I am nearing the end of rust repair work on my original owner '72, which was every bit as big a rust bucket as what you're facing after being a daily driver from late '71 to early '79 in, in order, upstate NY, central Iowa, northern WV, and western PA. Oh, the salt, the salt... It's taken the better part of a year and many thousands of dollars to get to this point (mostly because I am not a welder - that's a BIG plus in your favor). However, I do not regret one moment of this adventure and I am in the "happy phase" of the project now where I'm choosing my paint color ("Arrest Me, Officer Orange") and getting ready to build a stroker L6.

[=Enigma=]

Does anyone have a proper method of locating exactly where the crossmember mounting holes should be in relation to the front of the frame? Since they half arsed this part, I doubt they properly positioned it.

Hogie, the attached zip contains a PDF of the body dimensions for a 73 240z including the info you're looking for. I'm pretty sure this measurement is the same on the 72 but you should probably check a few more dimensions to ensure they are the same.

chassis-dimensions.zip.zip

[hogie]

That is extremely clear compared to the online manual...thanks

[hogie]

I have been putting in a fence at my house lately so havent had much time to do any updates. Essentially the only real work I have done on the car lately is wiring. Luckily that seems to be working at least.

I finally got a chance to pull out the angle iron and see what is left of the frame rails. Honestly the inside edge is not anywhere near as bad as I feared. Also the area around the frame double is solid.

Here is what we are left with on the drivers side. I need to get a couple more jack stands before i drop the other side down. Judging by the rust on the angle Iron I wonder if it was actually driven with that as a repair for awhile?

[a7dz]

I would cut it out weld it up and move on.