We hade a discussion in another topic, about retrieving filed way engine numbers, which originally stamped in the engine bearer.

I had a talk with my father in law, who works at a crime lab in Holland. He had to ask a colleague, as that was the one who did etchings. He told meit was possible to retrieve the engine number, as long as it was filed away, and not grinded away with an angle grinder. This usually takes too much material away.

The process involves some hefty and nasty chemicals, and it gives quite some fumes. The surface of the aluminium will be etched away slightly, to reveal the stamped number. However, one should be carefull not to damage the rest of the car, due to spilling etchant over it.

I will get the recipe for the etchant (involves copper, sulphuric acid, NaOH, and more) and I was also offered the following:
You can also bring the car to the lab, we can do it in a "lost hour".

Get to know the people, and all is possible...

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Vive la Marque !!

Dear Herman.

We often use a company to retrive such numbers which may have been rubbed or polished away. They also use an acid formula to remove any metal which is often forced into the bottom of the stamped numbers. Once this process is complete they then use enhanced photography to highlight the marks that are left. We have succesfully retrived numbers from front axles were they had been polished before plating, also from aluminium casings even if they have been overstamped. The process only has marginal effect on the material which easily polishes away without any trace or damage.

Malcolm

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Malcolm

Great info, thank you!

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Vive la Marque !!