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[Bruce_TPU]

@ Bill,

What do you mean about the stator's being of the wrong size?  Can you give more detail, please.   

@ All

I ordered from Mike, three high precision bearings for testing, for the stators.  He is pricing non magnetic bearings for us, and I will post it.

I want to test with both bearing and with N35's and N42's.  I will post some pictures, when everything has arrived.

Cheers,

Bruce 

[blue_energy]

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

Hey RB,

Al's scope readings show a pretty symmetrical curve, almost a saw-wave.

Are you measuring something different?

I have very little idea on how to interpret properly either measurement, but why do they not agree?

Check this out, Ken.  This is a visual representation of a couple of seconds of the contents of statorwave.wav (located in that rar file):

http://www.flickr.com/photos/23061056@N04/2210107679/

As you can see, it's basically a saw wave.

[crash_uni8]

@all replicators
have you guys had any more success?
or are you guys still waiting on the correct mags?

if you've had any success a short video would be nice 

[Omnibus]

...Do you think that would be a criterion for the correct rotor to stator magnet induction ratio?

@Omnibus,

I think that this 'GW-stator lock' we are discussing here is a factor of many things.  If I were to order these things in descending influence they might be:  rotor speed, stator rotational inertia, relative magnet strengths, distance between magnets, and stator bearing friction.  Did I miss anything?

What I find most curious was the one stator that slowly rolled over 180 degrees to match the polarity of the other stator facing the rotor.  Why should the magnetically balanced rotor favor only one face of the locked GW-stators?

Perhaps the rotor magnets were not as balanced as we assume?

You know, that seeking of the same pole by the two stators when they are let go again after being stopped is interesting but I don't know how reproducible that is. Unfortunately, I can't sustain a constant high rpm but when spinning the rotor by hand as fast as I can (not slightly, the way @alsealokin does it in the video) I've observed various behavior of the discussed two stators. I've seen them behave as in the video as well as having one spin again while the other at rest and vice versa. Therefore, I'm not sure what criterion that behavior of the two like stators might be.

[Charlie_V]

I got a question,

In Al's video on youtube, it looks to me that the counter spinning stator is not exactly 120 degrees with respect to the other two.  It almost looks like it is slightly closer to the stator magnet on the right than it is the left - maybe by 10 to 20 degrees.  Has anyone else noticed that?

[vipond50]

@ Bill,

What do you mean about the stator's being of the wrong size?  Can you give more detail, please.   

@ All

I ordered from Mike, three high precision bearings for testing, for the stators.  He is pricing non magnetic bearings for us, and I will post it.

I want to test with both bearing and with N35's and N42's.  I will post some pictures, when everything has arrived.

Cheers,

Bruce 

HI Bruce
I am in the process of machining a new Rotor to what my measuring with AC indicates. I do know that if the rotor magnets are not at the correct radius there will be No Joy. If the New Mag's work out as i hope then I will post them to the Group. I do not want anyone to work this until I see it for myself. No point in the others spending there funding on some thing that may not function. I have found this out that latching will and can occur even though the magnet radius is incorrect.
Will update what happens after testing.

Happy Testing
Bill

[geodan]

OK, for all the wannabe replicators (like me) out there, I just got pricing back from Small Parts Mfg. (Portland OR) for machining components as pe Jason's drawings... the prices look way too high to me until you get up to a quantity of 25 or so... I think that the first order of business might be to just see if there is enough interest to get prices down...
You can contact me and I can keep a list of people (forum names are fine) and what they want...
If we get enough interest to get decent pricing then we would each contact SPM directly and make our own financial and shipping arrangements, We would use our forum names to insure that we get the volume price. (BTW, I'm not making anything on this, I'll be paying same group price as everyone else...)

(If anyone can get us a better deal please post it here.!)

Please feel free to contact SPM directly with any questions... I'll be happy to keep track of who wants what...
I gave them Jason's drawings and they came up with this configuration... I'm sure that we can correct the quantitie etc...)

Package Price includes the following:
1pc HDPE rotor disc, 1 pc acrylic base plate,
1 pc derlin stator holder 6 pc aluminum dampers,
6 pcs 4-40 screws x1/2.
(I gave them Jason's drawings, Not sure how they came up with this combination of parts)
quantity   price (USD)
1     -     750
2     -     595
5     -     450
10   -     295
25   -     150
50   -      99

I asked SPM to itemize, in case people wanted just some parts but not all etc... this was the reply...

"The simplest way for me to break this down for you is by percentages...
 
I will honor piece prices as a percentage of the Original PRICE and QTY quoted on VQ772 as follows...
 
Rotor   45%    Qty 1 ( 750 x .45 = 337.50 Ea )  Qty 5  ( 450 x .45 = 202.50 Ea ) For Example
Base    40%    Qty 2 ( 595 x .40 = 238.00 Ea )  Qty 10 ( 295 x .40 = 118.00 Ea ) For Example
Stator    8%    Qty 1 ( 750 x .08 =  60.00 Ea )  Qty 5 ( 450 x .08 = 36.00 Ea ) For Example
Damper 7%    Qty 5 ( 450 x .07 = 31.50 Ea )   Qty 10 ( 295 x .07 =  20.65 Ea ) For Example **
 
** ( Price includes 6 Dampeners )
 
Please email me if you have any questions, and I will do my best to get you an answer...  Sorry for not breaking this down in a better format, as I am pressed for time...  If you need this quote formalized (like the original one I sent you), please let us know, and give us a few days, and we will have it for you...  Otherwise, I hope this works for what you need...
 
Thanks again for the opportunity, I hope that we can help you out with this interesting project...
 
Regards ~"
 
(The contact at SPM is...)
 
Mert Rockney Jr.
Small Parts Manufacturing, Co. Inc.
Email: mert@smallpartsmfg.com
Tel:    (503) 287-1181
Fax:   (503) 288-4753



geodan

[ken_nyus]

So what can we learn from combining the stator magnetic field change over time in the sawtooth pattern, with the stator speedup/slowdown over time as shown in Lumens experiment?

RunningBare, you said the sawtooth pattern was the last thing you would expect.

How about this thought experiment:

Take the pattern over time you would expect...
Now what shape of acceleration/deceleration would be needed to turn your expected pattern into a saw-tooth pattern?
It should be the same as the pattern seen by Lumen.

Or we could take the saw-tooth pattern, combine it with Lumens speedup/slowdown curve, and we should get the pattern you expected.

Hope this makes sense.

[Omnibus]

@btentzer,

I wonder if you found the address of the guys in Washington who offer the N35 cylinder magnets? I'd like to try rotor magnets of different strengths. Regarding the stator magnets, one problem I'm having is that I can't get the magnet and the bearing out of the encasement to try different combinations as @alsetalokin suggested.

[RunningBare]

The reason I was not expecting a sawtooth waveform, see picture below, excuse the image, it is just a rough analogy

If someone could confirm or show the field shape to be different please?

The way I figure it, the scope readings should have given sharp dips for point A and B
(http://cosmopod.com/mysite/barefm/op/statorfield.jpg)