I saw a video about someone that was making his own rubber lab with silicon carbide grit and flex seal liquid clear, seem very economical and could be used for the 80/180 grinding. cannot source flex seal liquid in my country tho : https://www.youtube.com/watch?v=NPOmJwgH6TQ
That's a coincidence, I watched that same video a week ago!
That Flex Seal rubber is actually not bad stuff, if you can get past the
bad TV commercials, lol. It is composed of styrene butadiene copolymer, which is basically car tyre material.
Looks like we can get cans of Flex Seal paste (rather than the liquid) here in Australia, a bit thicker than the gunk in the video, but should also work in a lap I reckon.
I've prepared a piece to measure grinding speed and will take macro shot of the result of each steps to compare once I get all of them. but metal being softer maybe the red/brown ones are not suited for gemstones
Looking forward to your results,
RC
