lrk stators

[toolmkr]

Hi all,
i have a lrk stator question I’m hope someone can answer.
So far all the stators I’ve seen are of the 12 slot type and are wound using 6 of the 12 slots. My question is, are the 6 blank slots needed. Being a tool & die maker it’s a simple task for me to wire edm a laminated stator stack and would like to make a 6 slot stator that will fit my current 22.7mm GB based design. 6 slots would make winding easier and give more room for higher number of winds

[ScubaSteve]

I'm sure someone will offer you a much clearer explanation, but I know that when using the LRK winding scheme, those 6 unfilled stator arms have a purpose. If you do a google search for "distributed LRK", you should find all the info you're looking for. The distributed LRK winding scheme fills all 12 stator arms. I haven't seen any info on 6-arm stators wound using the traditional LRK method, but then again that doesn't mean it won't work.

Sorry, more or less useless when it comes to LRK specifics. :oops:

[DadHav]

Hi Tool Man, I made a living in the trade for the first 18 years of my working career also. To bad it doesn't pay what it should. Right?
I ran into a string on the LRK forum. The person writing was obviously savy on the subject. He mentioned that after winding 12 legs that he would no longer be winding 6. I finished my first two LRK style motors with the GB stators and magnets. I'll tell you what man: I have my AXI motors for sale on E-Bay right know. I know everyone is gonna get sick of seeing my pictures, but this is how they turned out.
Good luck with your motor. If I can help I'd be glad to.
John

[ScubaSteve]

DadHav,

Gorgeous :!:

Winding all 12 poles, aka the "distributed" LRK winding method, supposedly had better efficiency, but I think since 12 pole stators haven't been readily available til recently there's not really enough test data to know everything we could know about these little powerhouses.

I think as soon as we have the GBx LRK hardware ready, test data will be much more common. :wink:

[DadHav]

Hi Steve, I heard you might have some nice surprises coming up with the LRK parts. I'm looking forward to it. If I can make a suggestion though: You might want to consider 4mm I.D. bearings and shafts for the larger motors. I'd be glad to help with some test data. I know Jay is giving it some thought.
Happy Motoring
John

[ScubaSteve]

You really think 4mm is necessary? Shouldn't be a problem, especially since the current plan is to stock blank shafts w/ no threading/step-down.

[DadHav]

Steve, Thinking about that: I did use 3mm on the single stator and thats fine. I'm sure there will be a lot of slow flyer props used. I have tested the single with every prop I have that was practical. The GWS 9-4/7 worked the best with two LiPo batteries. An 8-4 APS Park flyer prop with 3 LIPos was amazing. On the other hand I thought the slow flyer props were not the answer for the triple that I built. Graupner Slim and APC speed props really worked well with the bigger shaft and prop adapters. Maybe its just a matter of personal preference. Maybe someone else might offer an opinion. I will say this though I had to take precautions for the 4mm bearings that I found because of the larger outside diameter. I'd be glad to forward a few of my drawings so that you can see what I'm talking about. At any rate, some careful planning might be in order.
Thanks Steve.
John

[toolmkr]

thanks for the info
i orderd a few 12 arm 25mm stators
can't wait to see how the lrk wind works
compaired to my first motor a 22.7 gb stator
21 turn 26ga 5x5x2 n45

[DadHav]

Hey Tool Guy, Nice work. I wish I had a milling machine so I could do some of the cuts that you are doing. I have to do with an old South Bend lathe and a drill press. But what I don't have in machinery I make up for in spending way to much time on getting one to look good. Here's the two I have under test right now. Keep your air gap down to around .006 American measure, and I'm sure you will be surprised.
John
P.S. Do you think we could have a beauty contest for these guys.
P.S. I know Steve, Quit using up all your web site with these pictures, Roght? I can't help it. I have no grandchildren to carry on my name so I'm thinking about engraving some of these with the family crest and name. Maybe they'll be around for a while.

EDIT: Duplicate pictures removed as requested by Jay C

[DadHav]

Oh, One more thing Steve. Note on the pictures above that I have the front 4mm bearing inside the wall of the stator because the bearing tube was thin. Also in the back, you can see that the snug fit of the rear end bell mount gives extra support to the bearing.
John

[Jay C]

It's cool to post your pictures, but fo us poor souls on dial-up it's a bit much to post the same ones more than once in the same thread (on the same page ;)) It might be better (and conserve disk space, to upload them to your gallery/album and point folks to that to see more of your motors.

Of course disk space is cheap (I'm not paying for it :twisted:) a, I hate to admit it, your motors are very sexy :shock: :oops: :lol:

[DadHav]

Hi Jay, Man I'm almost beyond help. I didn't remember that the pictures were above. Can you get rid of the second pics and post or both?
Sorry everyone.
John
Sexy Ay, You don't need a shrink. I think that's a normal reaction from a member of this forum. Remember, I told you I put my most recent version on the dresser so its the first thing I see when I awake.
Sick, Sick, Sick.

[Jay C]

Hey John, I removed the dups. In the future if you need to do it, all you have to do is clcik the Edit button, then Posted Attachments, then Delete attachment for whichever ones you need to remove :)

Jay

[Happy|Harry]

dadhav those motors are simply stunning 8)

phil

[ScubaSteve]

Folks,

Just a side note... can we keep the size of the pics down? I'm always a fan of high-res images, but the whole horizontal scrolling thing is bothersome :? . Maybe if you just post smaller versions and save the high res ones for your gallery?

Other option is physically alterign the forum code to restrict the size of pictures attached to posts. I'd rather not have to (ask Jay to) do this, as I fear it may restrict gallery image sizes as well, so if you can all help out with keep your pic sizes down to reasonable limits, i'd appreciate it. Thanks. :wink:

[Q]

or you could simply use the "Shink attached image mod"

See http://www.phpbb.com/phpBB/viewtopic.php?t=175240

[Air Mover]

Hey all I have a big problem here ..


Need help getting a bell made for this lil guy..

specs are..

12pole L 35mmXDia. 42mm
8mm bore in the stator..possible more dont know yet all the same think a 5mm shaft will fit the bill so 5mmIDX?OD in the stator....current shaft dia. is 8mm.

here is a link to the motor..

http://unitemotor.com/Products1.asp?CategoryID=232&Recommend=1#

current motor specs turn a 18X8 Topflight wood at 3700rpm at 12v...
look at the lil GB stock stator.. .. the 40X55X8mm thick mags make the stator look micro for sure.. would like to add some big neo bars in there ... Steve tell George look out lol..=)
may install a few and see how well the motor performs prior to ripping it apart....I would hope to see about 4000rpm do to the extra torque...note at 3700rpm im getting 2.7pounds of thrust..

as a brushless lrk.. hope to get about 12pounds of thrust once configured to operate on a 80amp esc...

I need to find out about some neo bars.. 40X10X5..perhaps george can get 10 made for me.. as I want a 10 pole to insure could LRK Torque... with some reasonable rpm.. not sure of the prop size yet...like to stay under 24in dia...

anyway need a flux ring the Id is..54mm OD 59mm ... with a 5mm bore in the bell for the shaft and two locking grub screws...possible 3 grub screws maybe needed for 24in props....
After the motor is complete the next big prodject is a giant IFO .... with enough span to float but the power to go vertical and able to handle wind...
hope to use 3cell packs of 4400's.

Here is some pics..

[Air Mover]

another

[ScubaSteve]

LOL yeah i guess it does make the stock stator look a bit... insufficient. :wink: No doubt George can get the magnets you need - gonna be pricey though.

Those are razor scooter motors? :D

[Air Mover]

Yes scooter motors Steve.... these days they're getting more and more powerful.. in the amps they draw.. first ones use tobe 100w motors now there up past 500w with alot of raw torque....we can all benefit from the stators in them.. so look out for that used or trashed scooter...

Im guessing about 10 dollars per bar .. not sure what george has on hand.. much cheaper if you can buy what he has rather then a custom order...

This motor will be on going for some time to make it all happen .. once done though I .. should have a spiffy prop breaker... :wink: