not likely⌠usually the horns for such things work great with plastics, polymers, etc. but Iâve not really heard much about welding metal, especially to other metal.
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i put an xg3 in the tip of my left ring finger, just to the side of the gripping surface. Very worth it in my opinion.
For sensing?
Speaking of sensing Amal, out of curiosity, can you give us some details about the construction of the reputedly ânot that good for sensingâ xG3 vs a proper sensing magnet? In particular, the mass of the magnet proper vs the whole (or the glass alone) and the diameter of the magnet vs the diameter of the glass?
Iâm curious how much - or how little - extra mass / extra distance from the magnet it takes to dull out the sensations.
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How sensitive is it?
Somebody WILL correct me, Iâm sure. ButâŚ
I donât think youâd get good sensing from an uncoated xG3. (ignoring safety for this ex.) The coating mass hurts it to be sure, but the overall mass is too high to be sensitive to the relatively tight rapid vibrations in magnetic fields caused by A/C power. Itâs the old woofer vs tweeter argument.
In other words itâs not just the magnet mass vs coating mass ratio thatâs the problem.
The total mass needs to be low enough to get a good vibration going. The coating becomes a problem with low mass magnets because it eats up a significant portion of the low mass, leaving not enough room left to contain a sufficiently powerful magnet.
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The diameter of the glass is 3mm and the diameter of the magnet is 2.4mm. The length of the magnet is 12mm. The glass itself weighs 0.09g and the finished xG3 with magnet and resin weighs (on average) 0.73g
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Thanks!
It strikes me as if itâs not so much the performance âdragâ of the non-magnetic bits (glass and epoxy) as much as the size of the magnet itself that makes the xG3 less suitable for sensing. Itâs significantly larger, and therefore has more inertia, than a bona fide sensing magnet doesnât it? Wouldnât it be possible to encase a smaller magnet in glass, or is it too difficult technically?
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Iâm not fat! I just have big implants!
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Wouldnât it be possible to encase a smaller magnet in glass, or is it too difficult technically?
This is what I was wondering. There must be additional technical difficulties in coating a smaller magnet or someone would have done it years ago. What exactly goes into coating things in the glass the xG3 is coated in?
Itâs not easy, and even if you did do it the
total mass : magnetic mass ratio
would be extremely low
Exactly
I was more thinking about CVD glass coating, rather than a laser-sealed tube.
Iâve only ever heard of cvd coatings applied to glass, not glass cvd onto other shit.
Okay. Well thatâs just something that popped in my head. I know nothing about that particular process really.
I suppose I meant âsomething other than using a thick glass tube and sealing itâ. Like possibly wrapping the magnet with very thin glass fiber or powder and firing it for a few seconds: with any luck, the glass will fuse before the magnet gets destroyed. Or maybe a process that shoots molten glass onto the magnet.
No idea if things like that exist. I figured you of all people probably researched it.
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The problem with heating the glass to melting point, I think in the vicinity of 800°C it is the temperature for a magnet to loose magnetism depending on the type of magnet.
Not researched so Iâm am likely wrong, but regardless, 
and 
= 
Another guess here, but 800°C is Probably about 32,000°F 
in âfreedom unitsâ 
DAMN IT
Felt compelled to do research now ( First results, therefore not very thorough )
-
Glass melting is performed at temperatures between 700°C and 800 °C
-
800 °Celsius = 1,472 °Fahrenheit
-
Regular neodymium magnets are strongest operating up to temperatures of 80°C
Geez I wasnât even close on the neodymium magnets, but I do know they make hight Temperature neodymium magnets, Gah⌠more research
- For neodymium magnets , this temperature is very high , typically above 900°C to 1000°C.
That must have been what I remembered ( Still wrong )
That depends on how long you expose the magnet. You may well expose it to 5,000 degrees if itâs only for a few milliseconds. If what you want is coat the magnet with as thin a film of glass as possible, it might just be doable.
The biggest issue Iâve run into is manufacturing. A one-off are different from being able to mass produce for a price that makes sense. I feel like specialized production processes arenât likely to have a high yield at low enough cost that distribution is possible.
Every method attempted ultimately cost a ton to try out. I think in total, over the years, Iâve spent upwards of $50k to sort out a thin coating on sensing magnets that is robust and biosafe.
Sorry to yoink the topic a little bit but,
Steve Hawthornâs magnets. How do they hold up?
I have someone in my dorm thatâs had one for 2+ years now and his is still holding strong. Im considering one for myself if others can confirm they hold upâŚ
He basically was tinkering with silicone coatings since about the same time I was playing with RFID implants⌠I think since around 2005. For many years they failed⌠a lot⌠but I hear from people that failures are more rare these days. What I can tell you though is that only a few years ago I did an analysis on a couple of his mags. I talk about some of that analysis in my âboo hoo no more magsâ video;
In short, the material is not robust. It requires a lot of thickness to do itâs job well enough but still there is wear due to itâs plyability and the fact it doesnât stick to the magnetâs surface⌠it just swims around inside the silicone. To be fair, nothing really sticks well to the magnets, not even resins⌠but anyway⌠the other thing about silicone and how you manufacture such things is that it must be ripped out from molds which leaves the surface all fucked up and ripe for bacterial growth etc.
In general I just donât like the thickness, the wear, and the surface quality of silicone encased magnets.
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This is probably a good opportunity to clear up some misconceptions about how these magnets are made. The materials science is fascinating, and ranks up there with the lithium ion battery and the blue LED as one of the most influential scientific advancements of the last 40 years. The manufacturing process for sintered Neodymium magnets goes like this:
- NdFeB alloy ingots are produced and then pulverized in an inert gas environment
- Powdered NdFeB is compacted in the presence of a weak magnetic field to align the natural magnetic domains of the material. This means the physical structure of the magnet core is permanently aligned to be magnetic in one axis
- The magnet core is sintered in an oven to fuse the powder together
- Machining to achieve the various shapes and sizes
- Coating is applied. The most common is electrolytic nickel, there are many options.
- Now the cores are ready for their final magnetization, which is called âchargingâ. Usually a large air-core solenoid is used with very high current to induce a field in excess of 1 Tesla. This device is very similar to a rail gun, so the charging process can be very stressful to the magnet and itâs coating, creating micro cracks and faults.
Then, after some QC, theyâre ready to ship them out. Itâs important to note that there is really two âmagnetizationâ steps. One is matter (aligning domains) and one is energy (aligning electron spins). When you heat a Neodymium magnet above 100°C, the electrons start to receive energy and move more erratically in their orbitals. As the temperature rises, the electron spins are shaken out of alignment more and more until you reach the magnetâs Curie temperature at 320°C. At this point it loses its magnetic field strength. You can hypothetically âre-chargeâ the magnet in a magnetizer after this has occurred. Youâll recover most of the field strength that was lost, but you wonât get it all back because of physical changes to the structure. Also, remagnetizing puts an already compromised magnet through all the mechanical stresses a second time, and they often fall apart.
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