36" X 10" magnet wheel

[WCastle]

I have a large (36" X 10 ") strong magnet" wheel, it has 55 3/8" X 8" strong magnet poles, it was salvaged from a recycle center.

I have a generator design in mind but I am welcoming idea's - it should be interesting to see what idea's sprout !

here is a pic...

[WCastle]

Oh yes I almost for got it is indeed a strong magnet...

[rickoff]

Re: "Magnet wheel"

Do you have any idea what this came out of? Is there a manufacturer's label? It appears to have been shaft mounted to rotate. Will the iron pan be attracted at any location on the perimeter, or just in certain places? perhaps this part was discarded because of the fact that it became magnetized.

What do you intend to use it for?

[Chip Shorter]

A lot of times they use stuff like that in the food industry. Sugar refining for example is notorious for making stray metal so they use magnets to pull it out. Any time stuff goes from one process to another it goes through a magnet or metal detector.

That thing would make a great magneto.

[WCastle]

Rumor has it that it was from a recycle center ferrous - non ferrous seperator conveyor (that is what I was told) I guess they needed a wider conveyor as well as using an electro magnet to allow larger "chunks" to stick to the wheel instead of ending up in the non ferrous bin.

Yes the frying pan, or whatever other ferrous metal will stick to the surface,
however the poles are arranged NSNSNS.... all 55 of them.

the planned project will have some of the following components...

A whole bunch of magnet wire, some large high voltage caps, various 6" CPVC pipe and fittings, some 316 stainless steel wool, a 1 1/2" shaft, some heavy duty pillar block bearings, many drawers of assorted semiconductors...

well any way I want to see what some of the others here would do with it.

[rickoff]

Any updates?

Hi, just wondering if you have mounted the mag wheel with some shafting and bearings yet. First step, and very important, is to eliminate all rotational run-out. Next should be to see if you can get the wheel balanced perfectly simply by rotating it and marking the rotor at the bottom, when it finally comes to rest. Do that several times. If it is always different, then it is well balanced, but if it always stops in the same position then you will need to remove some metal by drilling at the heavy side, and make small adjustments. Do the magnets appear to have more or less equal repelling qualities? You can test them by inserting one of those tiny round Radio Shack magnets inside a piece of straight glass, or clear plastic tubing, slightly larger than the magnet diameter. Mark the tubing in 1/16" graduations, and insert the magnet at the bottom so that it will repel from the wheel magnet you are testing. With the wheel magnet at the apex position (top dead center), place the bottom of tube against the magnet and hold the tube steady and upright. Mark a number 1 on the perimeter, next to the magnet tested, and write down the repulsion reading on your note pad. Then rotate the wheel to do the same for all mags with the same pole (#3,#5,#7, etc.). Then invert the tiny magnet and do the same with all the opposite poles. This will tell you a lot about what you can expect, and what you may need to overcome. Are the magnets mounted in such a way that you can remove and reposition them? If so, you will want to position them for the best "magnetic balance." In other words, you wouldn't want the two strongest, or two weakest magnets close together. Good magnetic balance gives you a smoother rotation effect, just as actual weight balance does.

Hope to see some pictures of your progress.

Good luck to you, Rickoff

[WCastle]

Well, I do have a shaft for the rotor, however no bearings as of yet.

The magnets are an integral part of the wheel and cannot be moved.

my son has some of those "magnetix" toy magnets and we did a test similar to what you suggested, this is the reason I know the poles go NSNS the poles seemed to levitate the small magnets the same distance from the top of the wheel.

This wheel was made with high precision and I am hoping that is has good balance, as soon as I get the large bearings and a heavy duty cradle to support everything I will do some tests...


Will keep you posted ...

[rickoff]

Re: shaft & bearings

You might take a look at McMaster-Carr for shaft and bearings. Do a search there for "Mounted bearings." Chances are that flange mounted or pillow block mounted bearings will run you around $50 each, and you can find the shafting there too.

Question - Have you weighed the rotor? Since the wheel is not very wide, you could probably do nicely with a 1 1/4" shaft using press fit sleeve inserts (at the shaft ends) between the shaft and the rotor bore. That would work fine unless the wheel is very heavy, and you could then use the $15 pillow block bearing shown here:
1 1/4" Mounted Bearing UCP207-20 + Pillow Block Cast Housing:Ball Bearings:VXB

This would also save you $ on the shaft.

You can find the sleeve inserts (bronze) at McMaster-Carr as part # 6338K483 at $6.75 each:

Rickoff

[muttdogg]

Just what I was looking for

Rickoff, thanks, I had just signed on, looking for shafts and bearing, and the first thing saw was your post. Someone is mind reading, gotsta be wary, LOL. And they are cheap, too.Thanks again, Rickoff.
Dan

[WCastle]

Thanks Rickoff for the tip on the supplier, however I will likely be cutting some wheel bearings and spindle mounts from a truck frame at the junkyard so the cradle will have enough "beef" to hold this beast in place, the weight of this is awesome.

if nothing else it will make a cool flywheel

[ashtweth]

Roto verter as the prime mover with that as the flywheel. Frequency adjust the RV to the flywheel up to scratch.

[rickoff]

Shafts & bearings

Glad that helped you Muttdog. Anyone building a rotating device is going to need means to secure the rotating member. Normally that requires a shaft and bearings. Actually, the bronze sleeve that I suggested in my previous post (for reducing the shaft size needed) could be used alone on a shaft to act as a pretty decent and simple bearing, provided that you keep it lubricated. It doesn't need to be placed in the rotor bore, either. It could be press fitted into the shaft supporting framework. In that instance, you would probably want to secure the rotor ends to the shaft by using shaft collars having mounting holes for that purpose. See an example of the collars at:
McMaster-Carr search for part # 9677T4. You clamp this tightly around the shaft, and then use it to securely attach the collar to the rotor. You could also use a collar to attach some other device, such as a pulley, flywheel, gear sprocket, shaft extender, or magnetc coupling device. There are many possibilities, and of course there are also many different types of bearings and shafts. You can use a round shaft, or a D shaped shaft (which gives you a flat that is good for tightening down accessories that use a set screw for that purpose). You could also opt to use a shaft with threaded ends (inside or outside thread), or a shaft having a partial or full keyway cut into it. And there is nothing that says a through shaft must be used with a rotor. You can mount separate shafts at each end of the rotor using a design sililar to what I show here: Tube mechanics.jpg - Windows Live SkyDrive Note that this is just a rough preliminary drawing which does not show the bracing that would be required to keep the framework rigid, and does not show the mounting screws either, which are all 1/4-20 stainless steel. Keep in mind too that it is better to exceed shaft size and bearings beyond what what would be acceptable. This allows you to maintain precise gaps between the coils and magnets without vibration, and allows you to add more coils and magnets too. You want to start by building the best setup for the money involved. Later, you can upgrade the rotor bearings to ceramics, or even "magnetic bearings," which have zero friction since the shafting is actually levitated by repelling magnets strategically placed.

WCastle says his wheel is super heavy, so is going to find some timken roller bearings and front wheel spindles at an auto graveyard. Those will certainly be heavy duty enough.

In bearings, you want something strong enough to handle a continous load at the rpms you expect to run at, and you want to have as little rolling resistance as possible.

If you do want to use the rotational momentum to drive another device, keep this in mind: In small rotors, higher speeds will yield higher torque. In large rotors, and meduim rotors having a heavy flywheel, it is the momentum of the rotational weight that supplies drive torque, and you don't need much rpm's to do that. Flywheels also help to smooth and steady rotational rpm.

The trick is to think up ways of utiliizing as much shaft power as possible, without placing excessive drag on the rotor, rather than allowing it to go wasted. Use it to drive shop equipment, a water pump, a generator or alternator, a hydrosonic heat pump, etc: Hope this helps you to determine what will work best for you Muttdog.

WCastle, you really have your work cut out for you. It is so much simpler to use premanufactured, application specific parts when building, but I - like you - hate to see perfectly usable items at junkyards and recycling centers just going to waste. I love the challenge of using other people's junk to build with (making something from nothing, so to speak), especially when you come up with someting that works really well.

Best wishes to both of you, Rickoff

[muttdogg]

Shafts and rotors

Rickoff
Thanks again. Or according to my builder self, dang, got more to look up. This is the heads up I look forward to on this site.
Dan