The Bucking Magnet Motor

[z.monkey]

Now I have the Rotor re-assembled.  The tremendous forces of the magnets are causing the split taper bushing to slide around on the shaft a little.  I was able to find a sticky spot on the shaft where the Rotor would stay put.  I think I need to make a new shaft key that is just a little bit bigger.

I needed a couple shaft collars to secure the ends of the shafts at the bearings.  I went to the local hardware store, but they didn't have any.  So, rather than order them on-line, and pay shipping charges, I decided to make my own.  I took a couple half inch nuts and drilled out the threads to 0.500 inches.  Then drilled a 0.159 inch hole through one of the nuts facets.  I ran a 10-32 tap through the 0.159 inch hole, and inserted a 10-32 set screw.  So I made a couple half inch shaft collars for about 25 cents each, they are almost $2 at MSC, plus shipping.

The new mount holds the Rotor square, and solid.  There is none of the deflection that I had with the single sided mount.  Also I added the gear on the end of the shaft to help me turn the shaft.  With the magnets installed it takes considerable torque to turn the shaft.  Once you get the Rotor over the sticking point it will turn relatively easily.  I can tell there are repulsion and attraction points, and there are still the "sticky" point between the magnet fields.

Now its finally assembled, and I can start playing with it.  The next task is to figure out how to mitigate the eddy currents between the magnets.  I am thinking that I can use some small pieces of Iron to short out the eddy currents, and eliminate the sticky spots.

http://scientilosopher.blogspot.com/2012/05/uabmm2-new-mount-test.html

http://www.youtube.com/watch?v=Wza5glN2cjA

[z.monkey]

Been thinking about the cross currents between the magnets.  These cross currents cause the rotor to stick in various places where the face currents line up with and are attracted to the cross currents.  If you give the rotor a good spin it can overcome these cross currents until it looses inertia.

So, I've been looking into trying to mitigate these cross currents, and I figured that I can do this by shunting the cross currents by adding iron inserts between the magnets.  These modifications are meant to maximize the face currents and minimize the cross currents.

I needed to take the UABMM2 apart again to modify the Cants, and add the clearances for the magnetic shunts.  Also while I have the UABMM2 taken apart I made a new flat on the shaft to mount the split taper bushing tighter, and keep the rotor from slipping around.  This also gets the rotor to the position where I want it, at the bottom of the assembly, making space for the alternator part above.  More information here...

http://scientilosopher.blogspot.com/2012/06/uabmm2-magnetic-shunts.html

[z.monkey]

I've had to use a couple different thicknesses of sheet Iron to make the magnetic shunts.
Trying to be creative with limited resources.  I've managed to shunt about a third of
the Stator so far.  Going much easier with the thinner (20 mil) sheet Iron, rather than
the thicker (30 mil) sheet Iron.  My hole spacing is not as accurate as I wanted it to
be, and needed some flexibility in the width of the Shunts.  Now that I have got over
this hump the rest of the Shunts should be no problem...

http://scientilosopher.blogspot.com/2012/06/uabmm2-magnetic-shunts-2.html

[z.monkey]

Now I have all the magnetic shunts installed in the Stator.  The thinner gauge sheet Iron made the rest of the process much easier because I didn't need to file down the Cants.  I took a lot of the thicker (30 mil) shunts out and replaced them with the thinner (20 mil) shunts.  After reassembling the magnet motor I noticed that the Rotor took less effort to start, but now it is making noise because the shunts are moving, and making a ticking sound.

Next I need to install shunts in the Rotor.  I am thinking that I can use epoxy, and Iron filings and make a shunt that I can inject into the gaps.  Then after the epoxy cures shouldn't move, and make sound.  I noticed that when I was adding the shunts that they would be drawn into the gap between the magnets, and they like to be in there, meaning they are not trying to get away.  This means the Iron Filing Epoxy Shunt Injection Process might work smoothly, without making a magnetic glue mess.  I guess we'll see...

http://scientilosopher.blogspot.com/2012/06/uabmm2-magnetic-shunts-3.html

[z.monkey]

Now I have all the shunts inserted between the magnets.  The rotor requires less torque to get it started, and the rotor turns for a longer time when spun, so I think we're making progress.  Eliminating cross currents between adjacent magnets is the key to getting this thing to run.  This set of shunts is 16 mil sheet metal.  What we need is something that conforms to the spaces between the magnets better.  So, the next thing I am going to try is the iron powder mixed with epoxy, and injected into the spaces where I need to control the cross currents between the magnets.  We are starting to see the potential of the UABMM2 now.

http://scientilosopher.blogspot.com/2012/07/uabmm2-shunted.html

http://www.youtube.com/watch?v=_4xB5eUFmrk