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Underseal stripping and underbody assessment

Underseal stripping and underbody assessment

It’s very fair to say that this was not one of the most exciting or enjoyable stages of the project so far, but I knew I had to confront it at some point, so I bit the bullet and got on with it.

This was one thoroughly undersealed car! It must have been a quarter of an inch thick in places, so it seems previous owners must have been somewhat interested in keeping rust at bay at least – it’s just a shame it didn’t really work at all, given how many panels I’ve had to replace (or may yet still need to replace).

Here’s a view of the heelboard area, which seems to have been the best protected area of all, and consequently is generally the best preserved.

The central crossmember is a mess. It was already rotten and patched when I first bought the car, and I did some further half-hearted repairs to it in my previous restoration, but it warrants a proper job.

I knew the front right hand chassis leg (frame rail) was in bad shape, so I was already braced for a closer look at this, but it’s not pretty. It’s probably the kind of thing a smart person would walk away from when assessing a project, rather than consider trying to repair it, but I’m so far beyond the point where this car makes any economic or practical sense, so on we go!

Many hours of scraping later, and things are starting to look a bit better. With the underseal removed, that same heelboard area from above really did prove to be in very clean condition, just a few spiders of surface rust to be dealt with. Amazing to see how much of that factory primer had survived completely intact. All the red bits below indicate the locations of my previous repairs, which I had covered with red Hammerite I believe.

I removed the underseal in three main stages. First of all I painstakingly chipped it away using a variety of different scraping implements. The one I found most effective was actually a heavy duty wallpaper scraping tool with a particularly strong and sharp blade, which seemed to glide through even the thickest sections of underseal without much fuss. Having removed most of the material I then followed up with another pass using a wire brush to remove a lot of the stubborn bits left behind in corners, or nestling within spot weld dimples. Finally I went over the whole underside with a rag and liberal amounts of white spirit to dissolve and properly remove as many remaining traces as possible, and get back to something like a clean surface.

Neither end of the central crossmember looks any better with the underseal scraped away, worse if anything. I had replaced both of the outer jacking points last time around too, and they still look completely fine, but I fear they will be sacrificed nonetheless in the course of replacing the crossmember.

Another very “functional” patch covering up some rot at the front of the left hand floorpan. This floorpan had also rotted out along most of its length at the joint with the inner sill, and repaired with the rather dubiously welded patch visible on the left here. It’s all pretty solid still, and I need to remember that this car got through many years of MOTs wearing these patches, without even an advisory note, but it all looks such a mess now compared to the standard I’ve restored the rest of the car to this time around, so this area will be getting some attention.

So, over a year into this project, it’s really quite demotivating to now be confronted with the prospect of a serious amount of further bodywork and fabrication to do, when all this time I had in mind that the underside was still “good enough” and I wouldn’t really need to revisit it. Yes, I could leave some of it as is and press on and try to get the project finished, but cutting corners at this point seems ridiculous after all the countless hours and money I’ve already put into getting the car restored to a high standard. Decision made, there will now be a short break in proceedings whilst I work out exactly which panels and repair sections I’ll need and get them all ordered.

I couldn’t resist getting stuck in and chopping off that particularly sorry looking right hand end of the crossmember though, just to make sure there is no going back!

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