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Jun 10, 2003, 12:45 PM
Registered User

winding a 1 3/8" CDR motor?????

Does anyone know what winding and how many turns are good for a 1.375" diameter stator? It is exactly the same as the smaller CDR motors, I don't knw what it came out of but would be a great stator for a larger size motor. I would it with the green Radio shack wire, I think it was 14 turns or so and the motor was not very powerfull but did work then I redid it with the orange radio shack wire and it did not seem to work at all, it worked at very low voltage then as I increased voltage it only shifted back and forth and did not rev up, is this because the wire was to heavy or not enough turnes?
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Jun 10, 2003, 04:26 PM
homo ludens modellisticus
Ron van Sommeren's Avatar
Hi Eddy,

Can you post some pictures?
How many teeth are there in the stator?
How many magnets in the ring? If it's a circular magnet ring, use a screwdriver to count the number of attraction points.
What winding diagram did you use for the stator (link, site, drawing)?

Met vriendelijke groet Ron van Sommeren
diy outrunner brushless e-motor discussion.
Electric fly-in & lrk meet, June 22nd, 2003, Nijmegen, the Netherlands.
Jun 10, 2003, 05:44 PM
Registered User


This is the site I used to wind the motor

I used a magnet and there were 7 points of attraction.
Jun 10, 2003, 11:44 PM
Registered User
Try 10 t to 12 to start change the outer magnet to good neo's
2 magnets for ever 3 teeth witch on 9 teeth would be 6 magnets
closer the magnets fit to the stator the better BUT. Take a look at the LRK brushless site above. CU
Jun 11, 2003, 06:52 AM
homo ludens modellisticus
Ron van Sommeren's Avatar
I have never hear of 7 magnetpole motors, are you sure?

All teeth wound in the same direction?

Use a powerdrill to drive the shaft and measure the voltages, they should be the same.

As jmbig said, neodym magnets will give a huge improvement.

Groeten Ron
Jun 11, 2003, 09:18 AM
Registered User
Sorry, it is a 6 pole I miscounted. where do I get neodym magnets
the right sise for this motor? Should I use the green radio shack wire or something heavier?
Jun 11, 2003, 09:54 AM
Registered User
Anyway you wing ever third pole with one pice of wire all in the same direction rotation on the tooth then you do the other two
winds just after the first. It is almost better to unwind the orignal
to get the pattern. There are a lot of pictures at the LRK site. The six tooth stator is not as much torque as a 9 but it will work ok
Jun 11, 2003, 11:07 AM
homo ludens modellisticus
Ron van Sommeren's Avatar
I don't know about Radio Shack gear, I we are not talking plastic insulation here but lacquer coated wire? You have enough space to use thicker wire, the thicker the better (lower resistance, higher efficiency), or you can wind several strands in parallel.

-> photos
-> !winding ...

Originally posted by jmbig
... The six tooth stator is not as much torque as a 9 but it will work ok ...
Jim, I assume you mean the six magnetpole stator?

Groeten Ron

edit: changed faulty link
Last edited by Ron van Sommeren; Jun 11, 2003 at 05:15 PM.
Jun 11, 2003, 11:48 AM
Registered User
The winding link does not work
Thanks for all the info so far.
Jun 11, 2003, 11:49 AM
Registered User
Can the rotor be made out of titainum to make it lighter or does it need to be magnetic?
Jun 11, 2003, 01:19 PM
Registered User
I emailed the guy about the magnets he had 5mm square by 1mm thick will this work do I need 2 side by side? So a total of 12 magnets or will six do? The magnet in the motor is 5 mm wide by 2 mm thick.
Jun 11, 2003, 05:13 PM
homo ludens modellisticus
Ron van Sommeren's Avatar
Originally posted by Eddy
The winding link does not work
It does now.

Although I set the 'photos' and 'files' section to 'public', Yahoo insists on loggin in for the 'photos' section Don't worry, you will not get any spam from the list and you can set the 'nomail' option.

Titanium will not work. You need steel (not stainless steel).

You can cascade magnets.

Groeten Ron
Last edited by Ron van Sommeren; Jun 11, 2003 at 05:16 PM.

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