Saturday, 5 May 2012

What went wrong?

With the paint job on the DHC finished and the car slowly but surely being assembled, it is time to look back and see what went wrong with the paint.

The best solution we can come up with (and backed up by a few people who should know) points to the remains of the chemicals used for stripping the paint as the main cause for the problems. But why did it take almost two years for the discolouration to show?  This is almost certainly down to the fact that the car was out in the rain for a prolonged period waiting for recovery in Austria after the break down on the Timmelsjoch during the 10CR. This triggered the remaining chemicals to react with the water based paint causing the discolouration. The car was actually soaking wet inside and outside when it was returned from Austria.

So we followed the advice of the paint manufacturer Sikkens, and opted for a two pack paint. This kind of paint is officially forbidden in the Netherlands (due to health & safety issues) but may be used for specialist jobs. As a result of which it's only available on special order. Luckily we still had the old recipe to get a few litres of paint made. Added bonus of this paint is that its application is much easier, giving a better finish, as a result of which polishing out any blemishes is greatly reduced compared with the original paint job. Downside is that the paint alone cost nearly as much as the complete paintjob (including all preparations) during the restoration a few years ago!

And as usually in such cases the company that did the paint removal for Giessen (Mitraco in Belgium) wash their hands in innocence. Or as they say "In the 25 years that we use this process we never had any problems". Strange than, that a representative from a supplier who walked into the workshop, and after looking at the paint discolouration, only asked if the paint stripping had been done in Belgium? But worst of all is the fact that Mitraco even refuse to answer a few normal questions regarding the chemicals they use. Needless to say we won’t use them for future projects.

In the meantime I have been able to work on the car on and off and hopefully it will be fully re-assembled within the next few weeks. Leaving only the gearbox to be replaced by the one I am still rebuilding. Well actually I haven’t done much to it over the past weeks because I have been waiting for shims for almost two months now. Luckily S&S preparations managed to sent some over which where to thick but I was able to have them machined down a bit. But as the gearbox is at home and my tools are in the shed, finishing the gearbox will have to wait a few more days.

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