Those of you who weld are probably aware of this phenomenon, but I'm still a novice at this stuff and thought I should throw this out there as a beacon of warning to others.
Jim has been welding all of the structurally important parts of the Hoopty as we run across metal junctures, and mostly only welding up between the top half and the top two thirds. Some parts of the car are only tacked, based on potential need to change math and dimensions later on.
That practice has saved us twice already; once with the steering box and fuel cell reorganization and the need for the battery box to be relocated; second, the firewall-engine compartment framework didn't clear the carbs and had to be busted and re-worked.
Not a big deal, as far as we knew, to do the whole car that way until we knew we had everything where we wanted it. Heavy structural stuff, the tubing for the hoops, chassis and door bars are generally welded full round if we can get to all the surfaces. Stuff that's close to the ground or that's just too hard to get under was going to wait until the end of the project, right before sand-blasting and powdercoating. We were planning on rotating the chassis axially and using .030 wire to finish-weld everything that was tacked.
By doing that, we have created an Achilles' Heel. It got us when we trailered the car to the show yesterday. By strapping the car down with rods in place of the rear shocks, we created needless stress on the torsion tube -- which had only been hemispherically welded. The passenger's side broke loose, and now we're going to be another day behind schedule while we grind and rotate it back to the ideal position for a full weld.
(Continued ...)
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