70_Fastback: '39 GMC Truck Build Thread - KillBillet.com "The Rat Rod Forum Dedicated to fun, low budget, traditional, rusty, patina Rat Rods and Old School Hot Rods built with junk yard parts."

70_Fastback · #1 01-25-2010, 07:15 AM

I've been wanting to tackle this project for a while now, so I hit it running this weekend. I decided to chop the cab 5" in height, but only 3-1/2" for the rear window.

I rolled the cab outside and cleaned up the areas to be cut so I could weld easier.

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Rolled it back in and started measuring and laying out my cuts:

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Cut out the back window first. I only chopped the back glass 3-1/2".

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Then I remembered that I forgot to BRACE the cab... Doh! So I braced it and made the rest of my cuts...

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70_Fastback · #2 01-25-2010, 07:32 AM

I stuck the cut off roof back on. Here you can see the diference in how the front posts lined up:

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Next I halfed the cab top so I could line up the rear cab and the front posts and welded in the shortened window frame.

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Was happy with it so I started tacking it in place a bit more. Started on the driver side and worked towards the window from the B pillar.

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BUT... something was "off" somehow on the passenger side. The lower cab metal seemed to be bigger, maybe it was dented and stretched - I don't know for sure. But stuff would not line up like I wanted it to. I had to cut one stress relief in the lower part and one pie cut in the upper cab part to massage the metals to go where I wanted them to. I'm still not sure what happened here... but I think I remedied it. I'll just chalk it up to 70+ year old metal...!
(You can see the additional vertical welds in these pics)

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70_Fastback · #3 01-25-2010, 07:43 AM

Once the rear half was half-way secured, I moved up to the front half now. I had to make two relief cuts in the upper windshield corners to get the A pillars pulled in to line up with the lowers.

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Got the A pillars pretty well tacked up and cleaned up a bit.

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70_Fastback · #4 01-25-2010, 07:45 AM

Next up will be seeming in the roof piece and fabbing the 2 extra drip rail pieces. Then I'll tackle the doors.

What do you think? Look OK? I'm happy with it for my first chopping experience. And I even did it alone!