Yep that looks like the stuff I haveI've ordered mine from Amazon before. It's called Polyimide and it truly is an unusual type of tape. I used it to tape off sections while restoring the case on my 6139s and it works very well.
Any updates on this? I'm actually working on a similar project here in the US (begun well before I saw your post here, I must add), with some small success. Not really doing it as a commercial venture, more for my own amusement cleaning up junkers from the bay. I had the design worked out in my head so I had to go on and put it together to see if it would work. I can't post photos yet though, not enough post count. My setup is pretty well completed, but I'd love to see how you're going about it. Seeing the geometric brushed surfaces emerge from a beat up old case is a lot of fun and it's easy to get carried away!Also worth pointing out I am in the process of making a lapping machine for case refinishing and should soon be able to offer a service, at a small cost I need to do some practicing first and wait for my broken foot to go down to a normal size before I can stand on it long enough to get back to finishing the machine but watch this space!
It will be interesting to see the results, hehehe, bigfoot Tone:57:
BTW: I have not seen a CBX550 for ages, I rode mine into the ground and sold it for £25, yep it was quite good when I got it but 80K miles was too much for it.