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A labour of love

Final underbody welding

Final underbody welding

In amongst the bigger jobs covered in my last few posts, there have been a few other miscellaneous welding jobs to take care of on the underside of the shell, so I’m just collecting them together here.

With both floorpans now in, I needed to fit the new jacking points to the ends of the crossmember, but one of the rear suspension modifications I’m making to the car makes this slightly more difficult than it usually would be. I’ll later be fitting a 5-link rear suspension system from Frontline Developments, and in addition to that, Frontline also supply a Torque Reaction Bar kit, which helps to spread the forces from the suspension into the central crossmember, and is particularly advisable for high-powered conversions like the one I’m undertaking. The problem I ran into is that these bars bolt through the crossmember in around the same position as that usually occupied by the standard jacking point, so if I fitted the jacking points as designed it would be impossible to fit the bars squarely onto the crossmember, as illustrated below.

I could have just deleted the jacking points, which I assume is what Frontline do on their own cars with this setup, but I kind of like to use them, so I devised a little modification of my own. Since the bars need to bolt through the sides of the crossmember, I lightly redesigned and shortened the bracket on the jacking point so that it could be welded onto the bottom of the crossmember instead. Like so:

Next up, the bump stop for the rear suspension on the driver’s side had deteriorated and fallen off completely at some point, so was in urgent need of attention. With the 5-link setup I don’t actually require these bump stops any more, but I also don’t require a massive rusty hole in the chassis rail, so I fitted a new one anyway 🙂

I started by cutting it all back to good clean metal. This was all then thoroughly wire brushed out, treated with rust killer and painted…

…before fresh metal was let in to close off the chassis rail, and then ground back as tidily as possible.

A new bump stop support was then welded into place to complete the job.

Final job here was to replace the rear heelboard support, which bridges the back of the transmission tunnel. The old one was removed before I began replacing the floorpans, and as you might have seen in an earlier post, was badly holed with rust. There was still a bit of surface rust all over this general area, so I wire brushed it all back and treated it with Kurust, before etch priming it all (since access will become slightly tricky once the panel is fitted).

I pre-drilled the holes for the new strengthener and screwed it into place ready for welding.

I actually put a lot more plug welds into it than the original panel had, keeping in mind those additional forces the shell is going to be dealing with once this car is finished!

One more step closer to hanging up the welding torch and moving onto something different.

2 thoughts on “Final underbody welding

  1. Hi there, I am just about to embark on exactly the same body restoration. I was wondering if I could ask you a few questions?

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