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This is an issue for me and my company.

I'm building a prototype chemical vapor deposition system in a space with strong Chinese interest and activity. I picked Prusa 3D machines over Bambu because of the potential for losing critical proprietary IP with Bambu. Can't take the chance.


One has to be trained to do it, the untrained tendency is to wait too long. There's a USAF film on Youtube titled "Ejection Decision" that discusses this and shows how little time there is to make that choice.


De Beers built and has abandoned a very large CVD gem diamond synthesis in Oregon. This was their LightBox operation. They've transferred it to Element Six to rid the parent (De Beers) of the money sink, probably as a touch-up before a sale.

There was a fire sale of LightBox diamonds a few months back. I picked up 3 diamonds, all brilliant cut: 3ct. white, 2ct. pink, 2ct. blue. Total for the three was $600.


De Beers sells devices that can distinguish between naturals and CVD synthetics. They're not cheap, but less than ~$80K, IIRC. They do a pretty good job, I've heard >90% success in identifying CVD stones.


Diamond grit for polishing and grinding is now a cheap commodity. In 10,000 ct. lots, I pay from 5¢/ct. to 30¢/ct. depending on specific grit properties. I haven't searched for it, but diamond sandpaper should be a thing at these prices.


> diamond sandpaper should be a thing

I wonder, do diamond abrasives create any unusual safety/environmental issues when used around the house?

I can't imagine it being any more chemically-objectionable than tungsten carbide, but the structure and behavior of dusts could be different, etc.

The answer is probably that other things are still cheaper.


Unknown at present (nobody sells diamond sandpaper yet that I know of), but not likely. Diamond is as bioinert as gold, fluorocarbons, and similar materials in not provoking inflammatory responses when implanted in tissue. Your point about unexpected behavior of dust is a good one. AFAIK, the worst dust hazards (aside from outright chemical or radiological toxicity) are from spiky, acicular particles like asbestos. Diamond dust is either well-formed small crystals or blocky fragments, depending on how it's made. It doesn't exist in needle-like forms that trigger pathological responses from otherwise nontoxic materials.


Diamond abrasives are definitely a thing. But for sandpaper, you rarely need anything more than the typical ceramic or silicon carbide abrasives. They pretty much are relegated specialized tooling for polishing, cutting, or abrading ceramics, concrete, tile, etc.



The helmet cam video gave me a sense of just how difficult such operations are. I'm grateful we have people who will accept such assignments.


We turn off the AI note taker for the legal liabilities discussed in the NYT article. But we've also found its accuracy bad enough to warrant kicking it out, independent of legal issues. We have simultaneous participants from USA, India, France, Israel, and Estonia. Some have heavy accents (English is the meeting language). No problem for the humans, but the AI just can't cope (yet).


Arthur C. Clarke beat them to it - the thought, at least.

Watch This Space - https://en.wikipedia.org/wiki/Venture_to_the_Moon


Also, fine motor coordination often declines with age. Can make it hard to do a swipe or hit a key reliably in the first try.


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