Please help with gift for husband

[HallHandmade]

Yeah Frank... It's amazing to me how much pull the hub magnets exert on the plates (you don't want to get your finger pinched), BUT there is absolutely no noticeable magnetic attraction between a knife blade and the disc. The disc also does not attract steel dust... except for a very minimal amount directly around the magnet locations on the back side of the hub. Very well engineered.

I worked a lot in electromagnetics in a past life. I suspect I know how he's set up the magnets, it would be fun to take a gaussmeter to one of the backing disks and and see. Either way, you can kind of imagine that the field is taking the path of least resistance through the plate, almost like an electrical circuit. In my old job we would call it a shorting plate (somewhat similar to what is used on the back of a shielded speaker magnet), but I used that term once around a physicist and he threw a fit. Rather strange, as it seemed a somewhat common industry term.

 

[PT Doc]

I worked a lot in electromagnetics in a past life. I suspect I know how he's set up the magnets, it would be fun to take a gaussmeter to one of the backing disks and and see. Either way, you can kind of imagine that the field is taking the path of least resistance through the plate, almost like an electrical circuit. In my old job we would call it a shorting plate (somewhat similar to what is used on the back of a shielded speaker magnet), but I used that term once around a physicist and he threw a fit. Rather strange, as it seemed a somewhat common industry term.

I was curious about the magnet strength setup. What are your speculations on how the disc is setup? I have watched a video of the disc being removed and it looks like it takes quite a bit of force. It was stressed to keep you fingers out of the way when putting a disc onto the hub. Really cool design for sure.