Thread: Fab of bottom door panels for 1937 Buick

Tweet

Responses in blue

Originally Posted by Mutt's37Buick

Thanks very much for your insight. Most of my welding to date has been in the wheel wells and trunk so I was not as concerned about warping.
Yes the door becomes very flat as it moves up from the bottom edge. The rust is not all the way across so I will make small patches to handle small rusted areas.

More smaller patches is not always better. Given you are using a MIG, this machine introduces about the most shrinking of any process. Add more vertical lines for additional patches, and you'll add more areas of shrink. The vertical seams will pull inward into a valley.

I will work to replace the bottom .875 radius and back flange.
The back of the door is wide open for planishing and I planned on using a MIG welder.
I was taught to skip around a lot and make small dots to prevent warping, which is contrary to your recommendation of one a continuous to reduce warping.

The continuous pass would be for TIG or O/A gas welding only, after tacking to hold things in place. Yes, you are correct, we would not be performing a continuous MIG weld in sheet metal without blowing holes all over the place.
It appears that there is 1.75 OD mechanical tubing available in .049 wall thickness.
1) Would it be possible to slit tubing and weld to the front skin? After planishing, I could weld a rectangular tube, or angle, to the back for structure.
2) Do you see issues with this approach?

Unfortunately the shrinking effects of welding would come into play here again, so the section of slit tubing would tend to pull one direction or the other. My luck has tended to be the opposite of what one needs... So in the interest of minimizing the number of welds, my preference would be to make one patch of a continuous piece of sheet metal that can be installed with one horizontal seam, and this seam placed where it does the least amount of pulling..

Thanks