Endless Sphere

https://www.electronicsweekly.com/news/research-news/rare-earth-free-magnet-made-from-cheap-materials-2016-05/ Its nothing new that various thin films can be made twice as powerful as bulk Neodymium Iron Boron. But the trouble is they are just thin films. Many rely upon strain, which cannot happen e...

https://www.anl.gov/article/stronger-lighter-greener

Possible link to the original article? OP link roboplagiarized to the point of nonsense. I mean, "Neodymium" somehow changed to "Niobium"? Same things only completely different, nobody cares if we change a few facts...

Dip end of Litz bundle with lots of flux in a pool of molten tin. Enamel will usually burn itself off, unless its not real enamel. Pure tin melts about 48C hotter than regular lead/tin solder. May be part of the magic when burning off enamel? Our pool is pumped more like a fountain or volcano. Can r...

You post gold filled square copper wire and complain Litz costs too much?

Rectangular Compacted Litz.

Skin effect may not matter for reasonable motor frequencies.
But proximity effect still matters, as does breaking up eddies.
https://en.wikipedia.org/wiki/Proximity ... magnetism)

Neodymium magnets are 14 parts iron to three parts other stuff. 2 parts neodymium. 1 part boron. So much for eliminating iron... Samarium Cobalt: 5 parts Cobalt to one part Samarium. Extremely brittle, but won't corrode, and takes heat better. Definitely not saying Cobalt makes a better motor than i...

For no backing iron entertainment purposes only:
try searching: "Halbach Array"

https://en.wikipedia.org/wiki/Magnetomotive_force Word I was thinking of earlier but couldn't recall. Will need unreasonable large current, lots of turns of tiny wire to push big flux through empty space. Only because empty space is reluctant to pass flux that you can do work against it, and store e...

Maybe I don't totally get Faraday, or Topology, but a field might orient itself through the middle of the coil no matter how you bent it. What you going to do if this coil's field is perpendicular to your permanent field? Am I imagining the picture from too far to see some local effect you are tryin...

Failure to address reluctance of flux return path around outside of coil. Not a big deal, just embed in a pipe of laminated iron or bailing wire. Taking care not to complete an electrical circuit, only magnetic. Failure to address reluctance of gap for coil to pass through. Failure to address eddies...

Copy/Paste propaganda from JB's website. Q:How much heat can J-B Weld withstand? A:Original J-B Weld can withstand a constant temperature of 500º F. The maximum temperature threshold is approximately 600º F for a short term (10 minutes). Refer to individual product packages for more temperature info...

I havn't yet read everything I should between page one and last of this thread, trying to squeeze this visit into a very short break. Back in the beginning, you were mixing up some epoxy and powder that you first called ferrite then iron. So I don't know exactly what you mixed... Now when I do this,...

very embarassing....i have broken half of the surrounding magnet....it is part of the 850C display. So my question: can the device still be working or is it impossible? if anyone knows enough about this kind of coil...it should be just the shield..so maybe I am in luck.. You have reduced the induct...

Then let me ask a few physics question that's been puzzling me. Why does flux in free space mushroom around the easiest path instead of the entirety taking the easiest path? I'm assuming its like different resistors in parallel, but I'm not sure. Then you got quanta, which means lines instead of a s...

Solid state relays are bricks made of mosfets and isolated couplers selected for a different purpose. Why is this better than mosfets and isolated couplers selected for the purpose of driving a motor?

I've molded a few composite inductor cores of JBWeld (5% Ferrosilicon "steel" Filler). Can highly recommended for energy storage or flyback choke only, not for motor. Too much reluctance from too much distributed gap. Only conducts flux 3~6x better than air, which might be enough to guide the field ...

One of the things a proper working BMS does is drain overcharged cells. Hopefully before they overcharge too much and become hazardous. However, draining generates heat. Too much heat to keep pace with a charger of reasonable speed. Therefore the charge may shut off before completion, and the high c...

A stack of washer rings as you linked (pic shure looks like BB30 and cassette might be same diameter) could work. You say its been done already, so lets say I trust. OTOH: Looks like Lingbei GP could be the rare exception, not wanting/needing a ring. Some sort of cone shape fits inside BB30 or adapt...

This: AmericanMisfit.jpg Correction: Looks like this Bafang may have same problem, wanting same or similar ring. 01,02,HD, none are flat. What made me think they were flat? Better yet, why does Luna (who should definitely know better than I) make adaptors as-if all inside faces were flat??? another ...

Luna shape probably works fine for Bafang. For TSDZ2, you need the green highlighted ring chainside, as shown on Bikewow adaptor. Else BB30 surrounding ridge of TSDZ2 is all that touches (red) an American bottom bracket. Taking side clamping force in a bad way. Red is not a problem with this adaptor...

I "bought" Sturmey hubs and several things I needed from a seller that took the money and never shipped. My remaining budget for 3D is zilch. Hopefully the CSA trade goes better. Buyers regret over a buck worth of chopsticks, when I could have used twigs from the yard.

Re Rydon, let me take a wild stab in the dark guess. No facts, just speculation: Don't see how you could backpedal without the motor backpeddlin' along with you. I mean, wouldn't that strip a gear trying to spin the motor? Therefore you prolly got 500W of coaster braking assist. More than you may ac...

So, finding some new hope after losing a bunch of money on ripoffs. I decided was as good a day as any to bang out my bearing cups and try to fit TSDZ2 on the Electra I had originally intended it for. The hole through the cups was plenty bigger than 30mm, but the motor won't clear the bottom edge un...

SRM has to add and remove energy from a rapidly changing inductance. Braindead sinewaves won't produce the smooth result you might expect. There may not be any simple simple fix for silencing audible bumps that are harmonics of any reasonable direct drive cog rate. Now on the other (not direct drive...

The way I test N-CH FETs: 0) Disconnect any other source of power. 1) Disconnect any load that mimics a short (motor windings) 2) Using two volt/ohmeters to measure each other. Set one Ohms the other Volts. 3) Each need to output more than 4V on ohms test to have any chance of working. 4) Abuse one ...