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[Omnibus]

@vipond50,

I believe fine-tuning is the word here, as in any precise mechanical device if it is to be made to work properly. We have to have a leeway to adjust the several parameters we've identified. Nothing unusual in that. Maybe @alsetalokin has given enough clues. Now it's a matter of skill and, not in the least unimportant, of some luck. Think about reproducing someone else's results when you're doing research in a standard university setting. Many times it's as difficult as this one, if not even more difficult that this one, despite the fact that there the previous work has been published in peer-reviewed literature and not by someone popping up out of nowhere in an internet forum.

[vipond50]

@ All
This afternoon i finished up machining my Fourth Rotor. The rotor is based off the spec of 144mm X 18 mm. The material is UHMW and the Rotor mass with magnets is 266.8 grams.(8.8 grams heavy). The magnet slots are machined to a depth of 0.410" (10.4mm) so i could deepen them and bring the mass down closer to the mark. There is also a stand off on the bottom of the rotor that  could also be removed and still reduce the total mass to bring the RT closer to the mark.
Will look at this closer tomorrow.

Regards
Bill

[Bruce_TPU]

@Bruce_TPU,

"EDIT:
I wish we had the height from the top of the base to the top of the rotor."

Doesn't this dimension follow from the requirement that the bottom of the rotor magnets has to be flush with the top plane of the stator magnet?

Hmm.... I actually found what I was looking for, in the .pdf.  It would seem that I have my construct incorrect in several regards. 

Incorrect -
I am using a 1" brass 4-40 screw to hold my bearing.  On the underside of the bearing is a mini nut to hold the center race and then the rest screwed into the base plate

Correct -
I need to use a 3/4" long 4/40 Stainless Steel (interesting) screw.  I need a tiny Stainless Steel washer for under the bearing to hold the center race and act as a spacer for the bearing.

Incorrect -
I am not using Stewart-Warner Bearings for my Stators

Correct -
Order Stewart-Warner bearings of correct size from Mike, the bearing guy.

Small progress is good!

Cheers,
Bruce

[vipond50]

@Bruce_TPU,

"EDIT:
I wish we had the height from the top of the base to the top of the rotor."

Doesn't this dimension follow from the requirement that the bottom of the rotor magnets has to be flush with the top plane of the stator magnet?

Hmm.... I actually found what I was looking for, in the .pdf.  It would seem that I have my construct incorrect in several regards. 

Incorrect -
I am using a 1" brass 4-40 screw to hold my bearing.  On the underside of the bearing is a mini nut to hold the center race and then the rest screwed into the base plate

Correct -
I need to use a 3/4" long 4/40 Stainless Steel (interesting) screw.  I need a tiny Stainless Steel washer for under the bearing to hold the center race and act as a spacer for the bearing.

Incorrect -
I am not using Stewart-Warner Bearings for my Stators

Correct -
Order Stewart-Warner bearings of correct size from Mike, the bearing guy.

Small progress is good!

Cheers,
Bruce

Bruce
When U get the Spec on the Stewart-Warner bearing please let me know. I attempted to locate these, but had no luck.
Thanks
Bill

[Omnibus]

@Bruce_TPU,

I'd like to know that too although see again how nonchalant @alsetalokin is about these matters in a link @blue_energy gave couple of pages back: http://www.steorn.com/forum/comments.php?DiscussionID=59687&page=7#Item_21, :

No.
I mean, I scavenge most of this stuff from surplus junk equipment that I scrounge in back alleys.
And you want manufacturers?

These that I'm using now are for 3.5 mm shaft size, in a paired housing that slips into the rotor's central bore, extending down to a shock-mounted base bearing unit.

What I had in there before were just some generic flanged 1/4 inch bore unshielded bearings, and the shaft was a 1/4-20 brass screw. Not the most accurate arrangement.

Of course, I'm kind of dubious here, giving too much emphasis on what @alsetalokin says while on the other hand insisting, as is known, to have a strict copy of the working device. Ultimately, what's important is to have the effect reproduced which would be most likely by following the exact construction of the device, no matter what someone's opinions are and how nonchalant about the details he is.

[ken_nyus]

Correct -
I need to use a 3/4" long 4/40 Stainless Steel (interesting) screw.  I need a tiny Stainless Steel washer for under the bearing to hold the center race and act as a spacer for the bearing.
...
Small progress is good!

Cheers,
Bruce

Bruce,

The place I found these screws is:

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productID=1607

I went with 1/2 inch myself.

NT55-186   1   $9.00      $9.00      50/PK SHCS- #4-40 x 1/2

[ken_nyus]

Now.... The mass of the HDPE Plug...

Bill

My recollection was the rotor plug was Delrin.

[Bruce_TPU]

@ Bill
Of course!   

@ Ken
Thanks!  What does the SHCS stand for?

[AndreaGanora]

Incorrect -
I am not using Stewart-Warner Bearings for my Stators

Correct -
Order Stewart-Warner bearings of correct size from Mike, the bearing guy.

Small progress is good!

Cheers,
Bruce

@Bruce
I don't remember Al writing anyting about the Stewart-Warners beyng for shure the ones that worked properly as stator's bearing between the 13 he had, since he had some Stewart-Warners , but not enough of them , so he bought some other unlabelled ones . so is a good start knowing the maker of some of them but isn't shure they are the good working ones , at least not that I remember him mentioning  it .
just a notice 
keep the great work up

P.S. edited
here is A dimensioned sketch of the design for the stator magnet/bearing holders made by AL :

(http://www.ospmm.org/whipmag/maghold1.JPG)

[ken_nyus]

@ Ken
Thanks!  What does the SHCS stand for?

Socket Head Cap Screw. You will need an Allen wrench for them.

Also remember Al ground/cut down the heads, "for clearance".

This is the one part of the rig that I have played at putting together, and even clamped down it is a pretty loose setup, with the little washer underneath, and just the bearings trying to hold things straight.

[Yadaraf]

.
RE WhipMag history/construction and parts:

I find this large PDF to be the very useful.  It appears to have all of the dialog between Al and OC, as well as specs -- as they evolved.

... http://www.ospmm.org/whipmag/pdf/OC_motor_012708.pdf


Cheers,   

Yada..
.

[Omnibus]

@Yadaraf,

@overconfident's input is to be ignored altogether. It's only noise and gets in the way of proper replication of the device.

[Bruce_TPU]

Incorrect -
I am not using Stewart-Warner Bearings for my Stators

Correct -
Order Stewart-Warner bearings of correct size from Mike, the bearing guy.

Small progress is good!

Cheers,
Bruce

@Bruce
I don't remember Al writing anyting about the Stewart-Warners beyng for shure the ones that worked properly as stator's bearing between the 13 he had, since he had some Stewart-Warners , but not enough of them , so he bought some other unlabelled ones . so is a good start knowing the maker of some of them but isn't shure they are the good working ones , at least not that I remember him mentioning  it .
just a notice 
keep the great work up

Hi Andrea,

Nope, look again at what he says.   

Al:
"I had 8, they are Stewart-Warner, and I had to buy 5 more from another source, they are unmarked."

I interpret this to mean that his original source for the Stewar-Warner bearings was dried up and he bought 5 more from another source.  (but still the same Stewart-Warner bearings).  And when they arrived, they were unmarked.  Thus no serial numbers, etc.  My bearings are all unmarked also. 

Cheers,

Bruce

EDIT:
@ Ken
Thank you.  I will try Stainless Steel 4-40 from Lowe's.  I should not have to grind the head.  Still Stainless Steel.  I also need nylon screws for my dampers, not the brass I have.  Everything affects damping, magnetics etc. and as Omni has said, it must be tuned perfect and built/replicated perfect.  Only one on the planet works.  I take this very seriously as do many of you.  Let's make this happen.

[AndreaGanora]

@Bruce
Well better like that then 
I must have miss interpreted what he meant .
Cheers
Andrea
here you find nice and clear pics of the device :
http://www.ospmm.org/whipmag/

[Omnibus]

@Bruce_TPU,

That's splitting hairs. I also understand it the way @AndreaGanora understood it--he ran out of the  Stewart-Warner ones and had to buy 5 more from another, non-Stewart-Warner source and he doesn't know what exact source that was because they were unmarked. Now, if Stewart-Warner produces also unmarked bearings these new ones very well might have been Stewart-Warner as well but there's no proof for that. The only hope would be if Stewart-Warner is the only Canadian company producing bearings. Etc. ..., etc. ... I think we're trying to read too much into what @alsetalokin drops laxly here and there.