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[carbonc_cc]

I think this rotor should work.  Though it has a bit of friction and drag.

Now I just need to find a nice pizza pan to mount onto the rotor.

http://www.youtube.com/watch?v=TxMqa3WaulM&feature=channel_page

[sterlinga]

I spoke with Mylow this evening (~6:20 pm Mountain).

He's been looking all over for stator magnets.

I recommended that even though the ones I pointed out a couple of days might not be close enough of a match in his mind that he ought to go ahead and get them to give them a try.  There's a scientific pursuit here as well to find out what does and does not work, and to explore the ranges of operation.

Referring back to the test he did a couple of days ago in remagnetizing his iron stator magnet with neodymium magnets, he said, "the Neo magnets worked, but not like how I liked it."

A few days ago he went back to the place that had been remagnetizing his stator magnet and talked to the guy in charge, who was not at all inclined to help out with the project by continuing to remagnetize his stator magnet.  He said that the machine is very expensive to run and intended for paying commercial contracts.  It is used to magnetize magnets used in CNC lathes, to hold things in position.  He was dubious about what running that little magnet in his state-of-the-art machine might do to the equipment.  He did give a couple of referrals of others in the area who might be able to do this for Mylow, but when Mylow checked with the referred parties, they declined to help.

He's in process of documenting his re-assembly of the unit, taking video as he goes, and uploading them to YouTube.

In looking at the HJ motor photo some more, he said he noticed that HJ's stator magnet is higher than he has his.

He commented on CLaNZer's replication and commended him on the work he's doing.  He noted that the stator magnet is quite a departure, and he'll be interested to see if it works.

Mylow's goal for himself is to end up with a self-starter, so that he doesn't have to do anything with the rotor to get it to begin spinning other than to bring the stator into position.

Sterling

[X00013]

I spoke with Mylow this evening (~6:20 pm Mountain).

He's been looking all over for stator magnets.

I recommended that even though the ones I pointed out a couple of days might not be close enough of a match in his mind that he ought to go ahead and get them to give them a try.  There's a scientific pursuit here as well to find out what does and does not work, and to explore the ranges of operation.

Referring back to the test he did a couple of days ago in remagnetizing his iron stator magnet with neodymium magnets, he said, "the Neo magnets worked, but not like how I liked it."

A few days ago he went back to the place that had been remagnetizing his stator magnet and talked to the guy in charge, who was not at all inclined to help out with the project by continuing to remagnetize his stator magnet.  He said that the machine is very expensive to run and intended for paying commercial contracts.  It is used to magnetize magnets used in CNC lathes, to hold things in position.  He was dubious about what running that little magnet in his state-of-the-art machine might do to the equipment.  He did give a couple of referrals of others in the area who might be able to do this for Mylow, but when Mylow checked with the referred parties, they declined to help.

He's in process of documenting his re-assembly of the unit, taking video as he goes, and uploading them to YouTube.

In looking at the HJ motor photo some more, he said he noticed that HJ's stator magnet is higher than he has his.

He commented on CLaNZer's replication and commended him on the work he's doing.  He noted that the stator magnet is quite a departure, and he'll be interested to see if it works.

Mylow's goal for himself is to end up with a self-starter, so that he doesn't have to do anything with the rotor to get it to begin spinning other than to bring the stator into position.

Sterling

 @ sterlinga , you had me at "CNC",   sounds like the plant is producing mags for servo motors. Steppers use triangles, so servo motors it is, like as i RC cars that use servos, etc... Just wanna point that out, if you find the "standard" polarity for high quality servo motors you will have your FEMM info. Thanx 13

[sterlinga]

http://peswiki.com/index.php/OS:MYLOW:Latest#March_28.2C_2009

Note addition of permeability plate.

embeded at http://peswiki.com/index.php/OS:MYLOW:Videos#Assembly_Instructions_.2F_Sequence

http://www.youtube.com/watch?v=_0adKZ7q1Qg - nearly dead magnets still have some weird movements

http://www.youtube.com/watch?v=GVwkb-5JVI0 - Video that shows the aluminum disk spinning and its flatness

http://www.youtube.com/watch?v=G6j3XsUoITY - rebuild of the magnet motor; placement of the first three magnets. Magnet bar used for spacing. Not exact, "okay".

http://www.youtube.com/watch?v=7lTl_Wvs0MY - permeability plate added to one set of seven equally-spaced rotor magnets, "just like Howard Johnson has in his motor".
CLaNZeR runs a wind-down test and shows his rotor magnet placement.

[X00013]

Or find a servo motor near the diameter mylow used, and you have your stator mag from the original vids, I'll c what i can dig up !


@ Clazer, Thnx

[X00013]

as far as companies that are willing to do what mylows is not , i found this place     

http://74.125.93.104/search?q=cache:YLYzCE1e3CMJ:www.servorepair.com/why_choose.htm+remagnetize+service&cd=1&hl=en&ct=clnk&gl=us

and they say this

Why do we re-magnetize all motors?
It is important to understand that once a servomotor, stepper motor or tachometer has been taken apart for repair, it will usually not work properly again until the magnetism is restored to its proper level.
The signs of weak magnets or improper magnetism are low torque, high current and/or intermittent failures. We know how to solve these problems for you. We have the drivers and the fixtures necessary to re-magnetize almost any motor you send us. If a fixture does not exist, we will design and build one to do the job. We don't just re-magnetize a motor and hope it's right. We have the test equipment necessary to do the complete job. We check the flux density and pattern throughout the total magnet assembly to insure that you get the maximum torque the motor was designed to produce.*

 So, looks as tho all mylow had to do was send his build to this place and they will make it all better!, Thanx Gnite

[JRHall]

I ran a couple of experiments today.  Since I haven't been able to find the channel magnets I put together groupings of magnets made by sandwitching a neo between two pieces of bar stock I purchased at Home Depot.  The bar stock was 1/4 and 3/8 square in 1" lengths.  I set up a 1 1/4" X 3/4" U shape magnet on the rotor.  One note is this was run on Plexiglas, not aluminum. 

With the set up as described by Mylow I got the expected kick in one direction and the rotor was blocked in the opposite direction.  Magnet spacing in relation to the U-shaped magnet length made a huge difference in how well it worked.  Also, the U-shaped magnet face for N & S is .308" wide.  The 1/4" magnets worked better then the 3/8".  Based on the results I got today it looks like the stator magnet face width needs to be wider then the rotor maginets.

Since I am seeing the rotation with the incomplete setup I had today on plexiglas I think I will finish the setup to and hopefully will see the full rotation.  Three and four magnet setup gets just about a full rotation on very bad bearings.

[nyctuber]

I ran a couple of experiments today.  Since I haven't been able to find the channel magnets I put together groupings of magnets made by sandwitching a neo between two pieces of bar stock I purchased at Home Depot.  The bar stock was 1/4 and 3/8 square in 1" lengths.  I set up a 1 1/4" X 3/4" U shape magnet on the rotor.  One note is this was run on Plexiglas, not aluminum. 

With the set up as described by Mylow I got the expected kick in one direction and the rotor was blocked in the opposite direction.  Magnet spacing in relation to the U-shaped magnet length made a huge difference in how well it worked.  Also, the U-shaped magnet face for N & S is .308" wide.  The 1/4" magnets worked better then the 3/8".  Based on the results I got today it looks like the stator magnet face width needs to be wider then the rotor maginets.

Since I am seeing the rotation with the incomplete setup I had today on plexiglas I think I will finish the setup to and hopefully will see the full rotation.  Three and four magnet setup gets just about a full rotation on very bad bearings.

JR, Mylow indicated exactly what you observed regarding the width of the stator in relation to the rotors in this recent video. http://www.youtube.com/watch?v=OnhBevG5Sz8&feature=channel_page  Excellent that you validated this effect.

[capthook]

CLaNZeR -
Great to see you replicating this.  I (and I'm sure MANY others) look forward to your results!  Thanks for all you do!!!

- - -
As to remagnetizing the stator:
Using neos stuck to the stator for a time - say overnight - should offer reasonable results.
For example: take an N42 neo and force a small ceramic magnet in repulsion to the face of it.  Once contact is made, the ceramic magnet will actually 'flip' its poles so that it is now in attraction rather than repulsion. (basically 'remagnetizing it in the opposite polarity)

There are numerous ways one might orientate the neos to the stator magnet to remagnetize.  Attached is a pic of some examples.

#1 would be a good one to try, but may not produce the desired field.  #2 may be better, but it's harder to get a magnet of the desired dimensions with the poles through the length rather than the width/thickness.

Trying different arrangements of the neos to the stator and observing the fields produced should results in the desired fields at some point.
(edit: Summary: as Mylow stated his attempt to remagnetize his stator with neos was unsatisfactory, it may just require a different orientation and/or size/strength of the neos.  how/what arrangment did he use?  Magnet size/strength etc. etc.)

(sterlinga - might you pass these thoughts on to Mylow on remagnetizing his stator?)

Any other recommendations/orientations on this?
Any FEMM simulations that would show this/assist this?

- - -
Of interest (IMO) is the ongoing attempts to 'rig' neos into a similar stator field... please keep posting ideas/tests/results.
A neo driven device shouldn't demagnetize (at least so easily) and should offer greater torque meaning a more useful device. (that is IF the effect isn't ONLY due to the stator demagnetizing)

[derricka]

So, if this is a problem, and you know the actual pole configuration, you just wind a coil around it. Hit the thing with a high amp pulse of DC and it is back in service.

Hey BEP, great idea. Building your own magnetizer should be easy.  Start with 120 VAC fed through a 1N4943 diode to charge a 300uF 200V DC capacitor through a momentary pushbutton labeled "charge". Another momentary high current switch labeled "Magnetize" would dump the capacitors charge into a ten turn, 14-16 gauge, wire coil. The coil should wound just big enough to go around the end of the magnet. Of course, with the high voltage capacitor involved, building this circuit into a properly insulated case would be essential. Adding a fuse and a 1 to 5 Meg ohm bleeder resistor across the capacitor would also be a good addition for safety. 

P.S. For those tempted to build this circuit:
Don't build this circuit unless you are familiar with proper high voltage safety procedures!