Quoted from howdoyouafford:

Hi, I don't have any pinball but whitewater is the one I have the fondest memories of, especially the topper. I read through this thread and I made me curious how one would reproduce the topper. Earlier it was mentioned that Philip Grear was the original artist who made the effect and had some deal with Williams and was involved in making it. I found he has two patents on the subject:
6,760,959
6,361,702
Both of these seem to be the same process, You take a .0003" aluminum foil and layer it onto something pliant of the same thickness then mount it to a plastic plate and micro engrave parallel lines on the surface at about 100/inch. The artistry comes in making the lines in swaths that differ in angle (actually i'm not sure what the trick is, but i'm dying to know) so chaser lights reflect off of them to make the animation. I might buy a cheap damaged topper to put it under my microscope and see the artist's work, or what's left of the evidence. Then you electroplate nickel and iron onto the foil to .01-.03" and then peel the foil off of it (destroying the original I imagine) and stick it in a web offset printer cylinder and then use metalized mylar and heat pressing which will seal the mylar to a print coming out of an offset color printer in the outline of the die cut you make and press the engravings of the die into it in one pass. I saw someone allege they talked to Grear and was told the plates are no more. (This makes sense because it's a rolling press and plates do wear out and there are no plate copies. Would be interesting to check different toppers for different impression depths, though not sure how. Microscope?)
Trick is, it's still covered by these patents. I think it's 20 years from 1999 or 2001, so not sure if his estate still keeps up on the patent. The referenced patents are an interesting read.
I found another modern company "Dufex" that prints those decorative pattens in packaging and their similar patent
5,168,646
Which Grear references, patented in 1991. What's interesting is the patent I found that google referenced with the UK based Dufex was actually registered to NCM International Inc in Chicago where Grear was/is based. (I heard mentioned he passed in this thread or another? If so, i'm sorry to not have the chance to talk to this fellow.) There seems to be some history with this graphics trick. It's referenced in the wikipedia article on Lenticular Printing, though not a lenticular process and the image is created differently, but applied the same way holograms are to things like credit cards.
Which leads me to believe you'll have to do some microscopy to see the original engraving art from the White Water topper and save the pattern to a computer and re-engrave it by CNC or even do it close enough by hand which would be quite the work, then there is even mention of an acid wash (though not which acid to etch nickel/iron) to deepen the ridges after the electroplate to make a sharper depression, and the photos of the reproduction in this thread that were not 'good enough' seemed to be a full sheet of foiled cardboard like a bounce card material due to the metal background around the border of the print, where the original seems to be a hot transfer only where the foil part of the image is. I don't think this has the reflectivity of the original, mylar is quite striking when metalized like those plastic metal balloons you see at the florist or those greeting cards with unicorns and shimmering backgrounds.
I got obsessed and didn't want my research to go to waste. Hope it's interesting. Links to patents and materials removed cause it's my first day with a username.