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View Full Version : What about "stock" CD rom motors?


eyesoreracing
07-14-2007, 10:53 PM
I've been reading up on CD Rom motors and there's plenty of info on how to build them, but I haven't found any solid argument for WHY to build them. Why can't I just use the motor as it came in the CD rom drive? Someone enlighten me, please!

-Dave

TRASHBUG
07-15-2007, 12:51 PM
cdrom motors as they come from the cdrom unit are wound with light gauge wire and have weak magnets which equals low power. This means that they could possibly be used in a light model with a low wing loading. To use them for more normal modeling needs the stator wire needs to be replaced with heavier wire and the rotor needs stronger magnets.

olmod
07-16-2007, 01:59 AM
I've been reading up on CD Rom motors and there's plenty of info on how to build them, but I haven't found any solid argument for WHY to build them. Why can't I just use the motor as it came in the CD rom drive? Someone enlighten me, please!

-Dave
Its no longer a viable option to convert CDR motors ,but you have to go back when there was nothing cheap in the way of that size brushless motor available,and we have good kits available for motor builders because of this history that are as good and often better than factory complete motors.
The use of the unmodified CDR motor because of the big variety, and the design for what they are intended to be used for,most just wont be suitable ,not having enough power and the built in speed control has to be removed so a standard RC esc can be used.

eyesoreracing
07-21-2007, 05:13 AM
Thanks to both of you for clearing that up. I'll now stop obsessing over old computers, throw down $15 on a motor and get back to flying.

-Dave

MTDV
08-14-2007, 04:43 PM
I think I reply a little bit late, but CDrom motor must be rewired to use. Otherwise it is ver weak as other stated. I used 26 gauge magnet wire from Radio Shack to wire them up. Here are some experiment that I made. For 9-pole CDrom motors, on ball bearing and original magnet, I wired one of them with 15 turns on each pole (motor 1), and the other (motor 2) had 19 turns (a little harder). I used GWS with B size gear box with 10x4 GWS prop, and the result was motor 1 pulled 475 gram at 11V, 10A. Motor 2 was used on the same setup, and it pulled 450 grams at 11V, 6A.

I did that a few years ago, and now aday most Chinese brushless manufacture makes cheaper and cheaper motor and ESC. For example, https://www.unitedhobbies.com/UNITEDHOBBIES/store/uh_listCategoriesAndProducts.asp?idCategory=179&ParentCat=192.

I had fun to do that during the early day of brushlless motor.

ron_van_sommeren
08-19-2007, 10:47 PM
Excellent motor building articles by Brian Mulder, a must read, will prevent you from asking a lot of questions you even did not know you were going to ask ;) ;)
http://www.southernsoaringclub.org.za/
-> Articles by SouthEasterners.
-> Electric Motors - part 1-5

Do-it-yourself motor homepages, manuals/tutorials, checks and tests in this motor builders tips and tricks thread. The checks and tests may save you from frying your controller or motor. Thread is active, bookmark it for future reference and subscribe to it:
http://www.rcgroups.com/forums/showthread.php?t=240993 (sticky thread, at top of subforum)

Two instructive motor winding/assembly videos, 14 & 10Mbyte respectively.
http://www.utahflyers.org/
-> Motor Winding #1 & #2

Vriendelijke groeten ;) Ron