Jensen Genny

[tajim]

Just a quick update on the rotors. Below are a couple of pictures of how I decided to mount the magnets on the rotors. I machined a pocket in the plate for the magnets to fit in. I also drilled and tapped a hole in the center of the pockets so that I can remove the magnet if the need arises. I don't plan on any other means to keep the magnets on the plates. This way I can remove individual magnets should something happen to one of them or if I decided to replace them with stronger magnets in the future. This machining requires quite a bit of effort but I think it is worth it in the long run because it give me options. I drilled and tapped 4 holes in one rotor to allow for jack screws. After I finish the machining and mount the magnets I will add additional pictures of the assembly.

Below is a side view of the way I remove the magnets off the plate using the screws.

That's all for now.

[RP]

I like the jack screws for removing the magnets but I'm a little worried about the grinding of the screw tip into the magnet.  They make nylon tipped screws that would do well for this application.

Go to: http://www.mcmaster.com/ and put "nylon tipped" in the search box on the left to see what I mean

[dinges]

I like both ideas, both the pocket for the magnets and the jacking screw (which is necessary, of course, because otherwise you'd never get your magnets off; can't slide them anymore).

Will probably do the same as you when I get to the point of making the rotors for my 10 footer.

Excellent idea. Had read about it before, but good to see how it is actually implemented.

Peter.

[SparWeb]

That looks like it will work well.  Have you thought of a way of plugging the hole, preventing corrosion, that will allow removal of the magnets at some later date?  Leave a very short screw in it?

For the sake of others who might try the same thing, they should bear in mind that embedding a magnet in too-deep a socket will circumvent some of the magnetic flux.  Instead of lines that reach out to the opposite rotor face, the lines will be drawn down to the base plate.

With a software package called FEMM, I found that a socket more than 25% the thickness of the magnet will start to affect performance.

My 2 cents.

[tajim]

Thanks for the info. My plates are 1/4" thick and the pockets are 1/16" deep. The magnets seem to stay in place quite well. I am a little worried if they get hot and de-magnitize.Will they fall off into the stator? Hope not.

On another note I am thinking about electroless nickle plating to prevent rusting? any thoughts?