Hi Lou,
Sorry mate I don't know, want me to find out?
The casings went into a small booth, there was a lot of fluid draining into a tank underneath, so I would have thought, no way for cleaning in-situ.
The effect was amazing, really clean and a depth to it. The guy said that he can "adjust" the finish depending on pressure. I am going for a slightly polished look.
I think the engine will look really good when done.
The company is based in Golcar, just outside Huddersfield.