ah yeah, ok, that’s fair
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My cousin is currently looking into prototyping different prosthetics for hands in his practice. It wouldn’t be too far fetched for him to reach out to them for a quote or question.
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Perhaps … but they would probably immediately question why a custom non-blasted / coated version was necessary or prudent… want to work with them to figure out the best solution for their application etc… i mean it’s a nice thought but my style is more get what you can get and make it work without ruffling too many feathers haha 
At the moment I have multiple vendors I can source these from so there isn’t a single point of failure beyond the manufacturer discontinuing them… having to rely on a cousin doing favors long term doesn’t feel that solid.
Finally, considering the progress we’ve made in this thread so far, I think we are just a quick simple process away from dealing with the sand or whatever the hell this coating is, then we’ll be fine. I’ve ordered a 4k bullet camera I can 3D print a coupling for so I can put it onto one of my stereoscope lenses so I can easily record a video showing what I mean about the sand or whatever it is coming off with my scalpel and we can assess different polishing / removal methods in video format vs crap stills I take with my phone through the optic.
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Bump?
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Ok once I get back to my desk I’ll split it out… but derailment is also dt forum thing hahaha
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Who makes the magnets in the xG3?
A contract factory in China. They are actually very good at sticking to tolerances. I’ve been very happy with them for core magnets.
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Is it same factory that made the Titan’s core?
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It is not. That was made by a medical magnetics factory who also arranged the titanium casings with their machining contractor.
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Great shot! I want to say i read that the wall thickness is .2mm. That doesn’t appear to uniform. Is that the side wall or closer to the top/bottom thickness? The right angles in the casing moving out towards the weld are interesting. Maybe a mechanical joint that is welded? The radiusing of the top corners of the core on to the casing seem to suggest it was pressed in which would support this.
Sorry if any of this has already been mentioned.
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Got the camera today and printed a collar for it but it’s Valentine’s Day and long weekend with the kids so testing and footage next week!
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Ok I finally got my microscope set up on my desk so I can do this properly.
TL;DR
- The surface is treated and material of some kind comes off when gently scraped.
- This could be excess material used in treating the surface or oxidized titanium from the surface which has been blasted so badly it’s loose and easily comes off, or a mix of both.
- The effect of the surface treatment itself should encourage cell adhesion, which could improve sensing capabilities while making removal more difficult.
- A process is being explored to remove loose elements of material without destroying the efficacy of the surface treatment.
The longer version
What follows is quite rambling.. I cut a lot of it out just for sanity’s sake.. but what I did leave in is still quite a “stream of consciousness” thoughts-in-the-moment word salad. I will clarify some of the things I’m blabbing on about in text below the video.
- Even though I make definitive statements in the video, I can really only say that the dental magnet in question appears to have a partially treated surface wherein some material is left adhered to the surface of the titanium, which appears to come off when gently scraped.
- What might actually be happening is titanium dioxide which has been oxidized from the surface treatment itself is easily sloughing off.
- The treated surface may actually encourage cell adhesion to the magnet and create a better bond with soft tissue.
- Risks and health effects of any material that may come off the magnet post-installation are unknown at this time.
- Effort should be made to remove the loose material without destroying the surface treatment, allowing for some level of soft tissue adherence.
More work is being done now to test various buffing / polishing treatments which will address my concerns while not entirely removing the surface treatment.
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Random thought is my jam, so…
Thermal shock to separate. Now hear me out, heat is bad, I know, but what if you dipped it in liquid nitrogen? If it just wiped off after that, you could save alot of effort.
You’d want to consider the risk of popping the welds loose too.
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Well, to be honest I don’t think this is stuff just laying on the surface. I think it is;
- bits of abrasive material which is partially embedded into the titanium
- bits of titanium “flakes” sticking out of the edges of blasted out craters
Thermal shock might dislodge embedded bits of blasting material, but I don’t think it will do much for any “wispy” flakes of titanium that are barely hanging on for dear life.
My goal is to remove the flaky bits at the surface and leave the deeper pits alone to allow some cell adhesion.
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Desktop CNC with diamond encrusted bits then.
Once you’ve proven the process manually of course.
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Well I’m not wanting to cut it in half or anything Just some gentle treatment with some polishing compound perhaps.
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I was thinking more like take an aluminum plate, mill a close tolerance diamter hole in it that matches the magnet with a depth that leaves the crusted bit exposed. Route vaccum into the bottom of the hole, insert magnet, turn on vaccum. Bonus points if the bottom of the hole is steel (adjustable height?)
Now take one of These, and run it around the diameter so that it just kisses, thereby removing any thing sticking up but leaving the pits untouched. A few passes over the top, and then swap it out and run again.
The aim being minimal effort on your part (after setup) and a consistent repeatable process.
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Ah yeah gotcha… anyone got a desktop cnc? I had similar thoughts about setting up a jig and instead of using a CNC just using a Dremel buffing tool to test various compounds… I do like the idea of repeatability though. There are some other concepts I’m considering as well that would be fairly easy to get repeatable results with.
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I’m single, unemployed, have a cat. I know why I’m middle of the night shit posting, WTF are you doing up? 
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