The frame of the MGA is a unique design, it's midsection is bowed out towards the outside of the car to allow the floor and therefore the driver to sit lower in the vehicle. This is one of the reasons that the MGA is so much fun to drive. The driver's sense of the road is increased the closer he is to the road.
The frame is a closed design and uses actual wood for the floorboards. This wood can add to the deterioration of the frame, it sops up water and holds it against the metal frame increasing the chance of corrosion. Most MGAs, particularly the roadsters have problems with rust in the cabin section of the vehicle.
My MGA was no exception to rust. Most of the floorboard rails were replaced and sections of the frame itself were replaced. I've never done any welding before this project, but with the help of small mig welder and the internet (for reference and moral support), I've been able to repair the frame and I think I can accomplish all the welding I need for this car. I guess we will see. I'm very happy with the results so far. Why didn't I start welding long ago?
Original MGAs used a 12v positive ground system. Two 6volt batteries were placed in series and stored behind the driver under a steel cover. A lot of MGAs today have been converted to a single 12volt system and some have been converted to negative ground. Since I will also be changing to a single battery and negative ground, I have extended one of the battery trays by a couple of inches to allow for a small 12volt power source. I guess I will store my lunch in the other tray. Converting my generator to a small alternator will provide me with 20 extra amps of available power.
The cross-section tube at the front section of the frame is bent down to accommodate the transmission and it tends to take a real beating and usually shows major road scars. Again mine didn't disappoint, the tube was virtually crushed to the point where the bottom was flat. One method to correct this is to heat the metal and apply air pressure to the tube and everything should pop back out to normal. My tube was to far gone, it also had a large tear in it which even with my newly found "expert" welding skills could not get to hold any real pressure. So I had to replace the flattened out piece with a new pipe. The repair is almost invisible.
After all the welding repairs were completed I had the frame sand blasted. The results were quite satisfactory and no other weak points were uncovered. I then painted with "Chassis Saver" paint. This is a self leveling one part "epoxy" type of paint which I brushed on. The results, I think are great., the frame looks new. This paint has a very strong bond, it's also a rust paint so I didn't have to worry about any spots missed with the sandblaster. Be sure to wear gloves, it's very hard to get off your hands. It has no UV protection so you need to top coat if exposed to sunlight. I will be using a flat finish type to prime the inner panels before painting the body.
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