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[dean_mcgowan]

@CLaNZeR,

That's an excellent idea to arrange sending your rig to @alsetalokin for him to see if he can get it to work. Once it's sent back to you working you can help everybody else to set up his or hers properly constructed.

Yeah send it via cleanaway mail services .. just pop it in your bin he's sure to get it
Or maybe Omnibus can pretend to send it for you

[MeggerMan]

Al seems OK with responding to my tests, perhaps its because I'm a builder, with photos to backup my research and not an armchair merchant that rants on endlessly about the hopelessness of OU, conduct of others or how it should be best done...Ooops, I think I just hoisted myself on my own petard.

I'm trying to figure out a way where by I can get Al to monitor the stator's dynamic rotation during a sync, because the stator has a low inertia it may not be spinning uniformly and like someone else has mentioned, it could be doing "teacup and saucer" or "waltzer" type rotation, like you see at the fairground.
One way involves the use of some electronics and somekind of optical encoder, for example the wheel encoder from a mouse, but I would need to make this up and send it to him as it would be unfair to expect him to make it himself.
May be able to do it using a scope to read the input off the IR diode.
What I would expect to see is compression and expansion of the pulse train.
Even a sound card could be used, now that would be a low tech way of capturing the data.
Also, I may redo my motor driven stator to have the ability to move in relation to the motor so the two are not fixed, a sort of lightweight spring drive.

The thing I was thinking was posting him parts to test on his rig.

Regards
Rob

[Lakes]

Unless Al were to use a PO Box, I think the possibility of sending Al anything would be remote, as he prizes his anonymity above all else.   

[RunningBare]

Hope this might be of help
I used my sound card and constructed a transducer consisting of a ferrite core and around 20 turns of copper wire, the measurement is taken approximately 1 inch from the stator while I maintained AGW lock by spinning the rotor manually.
What your seeing is 2 cycles of the stator.
http://cosmopod.com/mysite/barefm/op/stator2cycles.jpg

!
!
!  O   []
!
!

Exclamations represent rotor edge.
"O" represents stator
[] represents transducer

And here is a 28 second audio sample
http://cosmopod.com/mysite/barefm/op/statorwave.rar

[hydrocontrol]

A
I'm trying to figure out a way where by I can get Al to monitor the stator's dynamic rotation during a sync, because the stator has a low inertia it may not be spinning uniformly and like someone else has mentioned, it could be doing "teacup and saucer" or "waltzer" type rotation, like you see at the fairground.
One way involves the use of some electronics and somekind of optical encoder, for example the wheel encoder from a mouse, but I would need to make this up and send it to him as it would be unfair to expect him to make it himself.
May be able to do it using a scope to read the input off the IR diode.
What I would expect to see is compression and expansion of the pulse train.
Even a sound card could be used, now that would be a low tech way of capturing the data.
Also, I may redo my motor driven stator to have the ability to move in relation to the motor so the two are not fixed, a sort of lightweight spring drive.

 If you can come up with a 'low tech way' I would be really interested so I could get some useful data from my setup. Still waiting on my laser tach but it only got shipped Friday so it will be another couple of days  :'( . I do have a Radio Shaft down the street and a computer so if you can come up with something using those I think it would be very helpful to all the replicators.

[hydrocontrol]

Hope this might be of help
I used my sound card and constructed a transducer consisting of a ferrite core and around 20 turns of copper wire, the measurement is taken approximately 1 inch from the stator while I maintained AGW lock by spinning the rotor manually.
What your seeing is 2 cycles of the stator.
http://cosmopod.com/mysite/barefm/op/stator2cycles.jpg

!
!
!  O   []
!
!

Exclamations represent rotor edge.
"O" represents stator
[] represents transducer

And here is a 28 second audio sample
http://cosmopod.com/mysite/barefm/op/statorwave.rar

Wow.. that is a cool solution. Interesting graph. It would appear that the field is not symmetrical or the spin is not symmetrical. humm.. Could it be so simple as to glue a chunk of paper clip to the stator to warp the field ? I have wondered how symmetrical Al's stators magnets are. Could it be that they are not perfectly diamagnetically formed and that the field is slightly tilted from the axis ? I think someone else suggested tilting the stator magnet. Guess it is something else I will try tonight with my setup.

[Bruce_TPU]

Good morning, All,

Last night, at about 2am, I realized a simple test, based on Al's video, to determine if our rotor magnets are close to matching Al's.

If you recall, in Al's video, after he sync's the one stator AGW, soon after, he stops, by hand the other two stators.  Okay, now, if you watch the two stopped stators, when Al removes his hands, they DO NOT start to respin on their own.

TEST:
My test is this, to all replicators.  Spin up your rotor by hand, and then manually stop the two identical stators, with your hand, and then let go.  Does your stopped stator's begin to respin??  If yes, the rotor magnets are stronger than Al's!!    

Please post your results and magnet strength of rotor magnets.

Cheers,
Bruce

EDIT:
I have already done this test, on my "toy".  And they did not like being stopped, at all, and immediatly began to respin!!

[Omnibus]

@btentzer,

Same here. Mine didn't like to be stopped either. Both stator and rotor magnets are N42. Need to replace the rotor magnets with N35.

[PolyMatrix]

@btentzer
Good thinking.

May I point out that the rotors spin at low speed but not at high speed.

Speculation: the high speed of the magnetic field passing the rotors is too quick to overcome the moment of inertia in the stopped rotors. Sorry I have a bad habit of stating the obvious.

[Omnibus]

@btentzer,

I was just gonna say that.@PolyMatrix beat me to it. Try spinning the rotor at higher speeds and see what happens. As I said, if I spin the rotor the way @alsetalokin does, the stators don't like to be stopped. However, if I spin it much faster, and remember he holds the two stators after the rotor has accelerated, my two stators remain at rest, only slightly trembling.

[Omnibus]

Just to mention this. In the other rig which I don't have with me now but where I saw the unusual behavior during the wind down the rotor was spun at much higher rpm--1200, something I can't achieve presently. The rotor there is with the recommended rectangular magnets. These effects which I think @CLaNZeR observed as well are important to be studied further but here we're looking for self-sustaining run. Therefore, it's important to replicate the machine exactly as in the video.

What amazes me is that one would expect a motor such as this to be a self-starter if real. That's why, as you know, I dismissed it out of hand initially. If the acceleration we see in the video is confirmed it would probably mean that some additional effects, aside from the expected electrodynamic ones, emerge when the magnets are in motion with respect to each other than when they are at rest.

[Rosphere]

...if I spin it much faster, and remember he holds the two stators after the rotor has accelerated, my two stators remain at rest, only slightly trembling.

@Omnibus,

Did you also notice the following:

...The stators just sat there, with one exception; the 'black-half in-facing' stator does not move, while the 'white-half in-facing' stator slowly rolls over 180 degrees and stops to present its black-half towards the rotor, making two 'black-half in-facing' stators.  The rotor is balanced magnetically, what is causing this bias?...

[sterlinga]

@CLaNZeR,

I got to thinking today, while revising the opening review at PESWiki.

If I were you, seeing how you've had such a hard time getting the spec magnets to work, I'd go back to your interim set-up as shown at http://www.youtube.com/watch?v=vZPI5BwccsA and try to optimize that set-up.

Go with what works.

- - - -

@All,

I've created a shortcut url for the PESWiki OC MPMM open source project home page: http://www.OC-MPMM.com

[Omnibus]

...if I spin it much faster, and remember he holds the two stators after the rotor has accelerated, my two stators remain at rest, only slightly trembling.

@Omnibus,

Did you also notice the following:

...The stators just sat there, with one exception; the 'black-half in-facing' stator does not move, while the 'white-half in-facing' stator slowly rolls over 180 degrees and stops to present its black-half towards the rotor, making two 'black-half in-facing' stators.  The rotor is balanced magnetically, what is causing this bias?...

Yes, I do. Very interesting. The stators aren't even trembling as mine do (although my rpm are lower). Hard to reproduce it though. Have to spin it at constant 1200rpm. Do you think that would be a criterion for the correct rotor to stator magnet induction ratio?

[CLaNZeR]

Busy day as usual this end.

Have posted First New Tacho results and movie link so you can see the latching occur.

http://overunity.org.uk/forum/index.php?topic=71.0

Sorry cannot be bothered to type it all again LOL

(http://www.overunity.org.uk/ocpm/tachomount.jpg)

Cheers

Sean.