01-05-2019, 06:38 PM
Howard when I was starting off with my new single seater, I used a '28 chassis that had been hanging on the various workshop walls for 40+ years. It was bent like a banana and had multiple holes & cracks in it. As I wasn't going to use the original engine mounts, I fitted a length of 38x38x2mm square tubing into the chassis from underneath & welded it all together
I first cleaned up the inside of the chassis really well & the outside of the square tube, coated both in a thick layer of Wurth zinc rich weld-thru primer and while it was still wet I slid & hammered the tube into place. It goes from the nose piece to the brackets for the brake cross shaft. To secure it I clamped it with some large C clamps and blocks of wood. This effectively straightened the sagging banana curve
I welded it to the chassis at 1" intervals. As I wasn't using the original engine mounting holes I welded them to the tube and I had also cut the cracks well open with an angle grinder & I welded those closed & simultaneously to the tube as well.
Not the solution perhaps for the purist, however the bottom edge of the square tubing could always be sectioned off to form an inverted U inside the existing chassis rails. As I was building a race car I wanted the strength, hence the 2mm wall thickness.... but on reflection 1.6mm would have been just fine & less weight
Aye
Greig
I first cleaned up the inside of the chassis really well & the outside of the square tube, coated both in a thick layer of Wurth zinc rich weld-thru primer and while it was still wet I slid & hammered the tube into place. It goes from the nose piece to the brackets for the brake cross shaft. To secure it I clamped it with some large C clamps and blocks of wood. This effectively straightened the sagging banana curve
I welded it to the chassis at 1" intervals. As I wasn't using the original engine mounting holes I welded them to the tube and I had also cut the cracks well open with an angle grinder & I welded those closed & simultaneously to the tube as well.
Not the solution perhaps for the purist, however the bottom edge of the square tubing could always be sectioned off to form an inverted U inside the existing chassis rails. As I was building a race car I wanted the strength, hence the 2mm wall thickness.... but on reflection 1.6mm would have been just fine & less weight
Aye
Greig