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Paintwork part 1 – initial bodyshell prep and stonechip protection

Paintwork part 1 – initial bodyshell prep and stonechip protection

Not many progress updates for a while, but I have still been busily working away on the car whenever I have time. Very pleased to have started on getting the bodyshell into shape for painting, so here’s a quick summary of everything that’s been done over the last few weeks.

After finishing welding, almost the only part of the car still wearing any of the old red paint was the bulkhead inside the engine bay, and the slam panel at the front. These were both completely sound, but I stripped them back to metal and treated a small amount of surface rust in both areas.

That done, I epoxy primed the whole of the engine bay. I’ve been using U-POL’s rattle can Raptor 2K epoxy primer for small-ish areas like this as I go along. It would be an expensive way of covering large areas if you had a lot to paint at once, but it’s a convenient way of getting epoxy onto bare metal area-by-area without having to get spray equipment out etc.

Inside the car there was still a fair bit of the original Bracken paintwork around the heelboard and transmission tunnel areas, but again it all had a good scattering of surface rust, so it was all stripped back as well.

Underneath, the only original metal I hadn’t previously attended to was the other side of the heelboard and the battery box, so they were also sanded back, with any spots of rust attended to.

At this point the whole of the interior and underside had been fully sanded and prepared for priming, including all of the new panels (which mostly just needed a rub down with a red Scotchbrite pad to key the E-coat for painting). Next step was to mask up the outer panels of the shell, and then turn my single garage into a makeshift spray booth using a lot of polythene sheeting.

Then it was full steam ahead with getting it all into epoxy primer. For this job I used Jotomastic 87, which is a very high solids epoxy mastic coating. It’s designed for marine use in areas at high risk of corrosion from salt water, but seems to have found a lot of favour in car restoration circles for that reason – hey, if it can stop boats from rusting at sea, it should be able to keep a bit of rust at bay in an old sports car!

I put two good thick coats onto the whole of the underbody and interior, and it looked fantastic straight out of the gun, even though I was only using it as a primer. Seeing everything all painted in one colour really transformed the whole project – a very significant motivator after all those desperate months of welding!

With that paint looking so good it was almost a shame to have to move on to seam sealing, but needs must. To really maximise the chances of keeping rust at bay in the future, I left no seam unsealed, inside and out – way more than Abingdon would have originally bothered with I’m sure. Not a fun job for me, but hopefully a worthwhile one.

I switched to white seam sealer for the engine bay, since it would only be covered by primer and top coat I figured it would be less likely to show through.

Final job in this update was applying anti-stonechip protection to the whole of the underbody. I chose to use U-POL GraviTex for this, which proved to be a great product with a really nice finish. It’s supplied in 1L bottles which screw directly onto a schutz gun, making it very convenient to use. I bought a pack of 6 bottles including the gun from one of the big paint wholesalers on eBay for a bargain price, and used all 6 bottles, it was just enough to cover the whole car with 2 generous coats.

A note of caution: this stuff is messy! I’ve used similar before, so expected quite a bit of overspray and masked up the shell accordingly, but it still managed to find its way into places I didn’t expect, which needed a bit of a cleanup job afterwards. If you don’t want it GraviTexed, cover it up.

It’s worth the mess though, the finish looks great and feels like it will be very robust for a long time to come. The texture of the finish can be adjusted by modifying the pressure of the gun from the compressor – higher pressure makes for a smoother finish. I think the instructions recommend between 50-90 PSI, I went down the middle at about 70 and this is how it turned out.

Next time, some actual paint, hopefully!

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