Thread: Chassi Rust Repair (Series) - Need Advice

Newbs,
Using a single phase stick welder will be quite adequate. Measure the thickness of your chassis and buy some off-cuts (probably 2- 3mm) and practice your welding on the bench, until your practice joints can be bent in the vice for 180 degrees without breaking, or cracking.

For vertical welds use vertical down - high amps (use the maximum on the packet); fast travel; no weaving; rod about 5 degrees below horizontal (virtually the same for MIG). 1.6 mm rods are ideal, but I have the feeling they are hard to get nowadays, so you might have to use 2.5mm. If not enough penetration is produced on your test-pieces, slow down a trifle, or tack the pieces together leaving a gap (about 1mm if you are using a stick; I left 2mm using my MIG).

I wouldn't bend the patches unless there was a bend on the original; join where the original was joined, is good enough and often easier. On the vertical face of the chassis side, it will distort badly unless you support it on the inside. I used wooden blocks and wedges cut to size, to force the panels into place and secured as necessary with clamps. If you have a join with too large a gap, clamp a piece of copper, or brass behind the join and weld over it; then remove the copper. Tack all of your repairs at about 25 mm intervals and weld the seams in small stages, allowing the work to cool between welds; this is most important on large flat areas such as the vertical faces. Too much heat too quickly, will bend the chassis and leave you with an expensive and useless item. On my Series 1, I made a giant banana by welding my freshly fabricated rear crossmember without clamping it to something solid first; fortunately I was able to unbend it, but the moral of the story is, hasten slowly and double-check everything.

Cheers Charlie

G'day Newbs,
Just remembered that you wanted to have a bolt-on crossmember. If you do that you will need to put crush tubes (they are really anti-crush tubes) inside the chassis, so that tightening the bolts doesn't crush the chassis member. Use a bit of light tube of an appropriate diameter and tack them at each end so that they always stay in the right place; do this with the new crossmember temporarily bolted in place. This means of course that the bottom of the chassis (or top) needs to be put on last, so that you can access the inside - another reason why assembling as per the original joins is convenient.

When I did my chassis I totally stripped it first and set it up on nice tall trestles, to save my back. By turning the chassis over, I could access the underneath quite easily, which made welding easier. Before I: welded the ends on the front of the chassis; attached the rear crossmember; and welded the new bottoms on the longitudinal rails; I took it to the sandblaster so that he could blow all of the crap out of the inside of the rails.

I wrote a series of articles for my Rover Club magazine; unfortunately the photos aren't very good, but if you would like copies let me know your email address,

Cheers Charlie