I Like Welding ... or How To Put a Bucket Seat in a LM 500

With my semi-daily-driver Ringo soon to be parked in someone else’s garage, I needed to get Glinda roadworthy again. Currently, she’s occupying the driveway with her interior in disarray. Before last night the only front seat that would quickly bolt in was sitting in one of the Corvair Ranch’s buildings, so something had to be done, and quickly, to get the Cobalt bucket seat bolted in a space where no bucket had gone before.

I tried to find a good photo online of the front foot of the Cobalt’s seat track, but was unsuccessful, so the following, poor enlargement with red highlighting will suffice to enlighten what I needed to deal with. Coincidentally, this configuration is somewhat like an EM with hooks on the front of each track that go under a __|~~~~|__ shaped bracket bolted to the floor.

In preparation for installing these seats, I bought a piece of 1” square steel tube from Home Depot. My plan was to weld inch-an-a-quarter long sections of the tube (cut with the a disc in the angle grinder) to the floor and slide the feet into the open end. Since the foot was taller than the ¾” opening of the tube, I cut down the feet to fit. This also slightly lowered the seat in the car. LM 500s with their front bench seat only came with threaded mounting holes in the floor for the outboard ends of the seat – no inboard holes. I lined up the rear mounting hole of the new seat’s track with the outer threaded hole in Glinda’s floor and, fortunately, the center of the seat matches up with the center of the steering wheel – TYL. Using masking tape, I marked where the two tube pieces needed to be welded to the floor and then removed the seat. Out came the wire wheel and off came the paint in the areas where the welds would be. The sections of square tube made a visit to my bench grinder’s wire wheel to remove any external coatings that would impair the weld. I placed the first section on the floor holding it in place with a block magnet, connected the ground cable of my MIG welder to the nearby center seatbelt fitting that’s bolted to the body, and proceeded to lay down a bead of molten metal. The welder was set for melding sheetmetal, so I bumped up the heat and feed since the tube was significantly thicker than the car’s skin. While the first line was not that pretty, the next two looked pretty good (see below – you be the judge). I welded in the third and fourth sections replicating the spacing I’d measured from the actual seat. The moment of truth came when I hefted the seat back in, slide the front of the tracks into the ends of the square tubes and happily saw the outer rear hole line up perfectly with the threaded hole in the floor.

I haven’t figured out what I’m going to do with the rear inboard hole yet since it sits partially on top of the tunnel. I’m leaning towards welding in a piece of 5/16ths threaded rod. All in all, a good night in the driveway.