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mescalinedreamz
08-30-2008, 03:07 AM
I took apart a cd-rm. I have the motor out and the bell off. Now i see three wires soldered to the electrical board, M U and V and on the other side of the motor i see some wires inbetween the stators not soldered to the board but to themselves. I have read the 1 hour cdrom motor. I am a hands on type learner. I read, make sure its a delta or something in one of the pics. I thought all brushless are either delta or the WYE. Which i think this motor is. Now cant i unsolder the 3 solder points where W U and V is on the pcb board and put those wires to my esc? But first check ohms to make sure everythings ok first? Can this little cd-rom motor be strong enough for a pico-s litestick direct drive? Im new to all this sorry.And also, i always see a whole bunch of magnets glued, this bell on my cd-rm motor has a complete round disc that is a magnet.Not individual, is this better? i suspect not. Cause if it was then all these brushless kits wouldnt come with a whole bunch of little ones. So desolder the three connections to the pcb and i have myself a tiny brushless motor? Thanks

flydiver
08-30-2008, 03:58 AM
I've never taken one apart but from what I've read it's probably not worth it unless you just want the experience.
If you want to learn to wind motors starting at that level is what I did.
Get a GBv ($10) kit from GoBrushless.com (http://www.gobrushless.com/shop/index.php?app=ccp0&ns=prodshow&ref=GBv)
Go and read the tutorial for more info-there's a link there.

The GBv would likely work well on the pico-it is basically a reworked CD-ROM motor as I understand it.

I JUST got a GBx motor going and have wound but not soldered a TowerPro re-wind (bad original wire).

This is a big area with LOTS of discussions and a lot to learn. Take a look at this page and follow some links:
FAQ - cd-rom tips'n tricks, may save your ESC! (http://www.rcgroups.com/forums/showthread.php?t=240993)

Somewhere on that page you might find how to take one of those apart and rework it. I've seen it somewhere and rapidly determined I did not want to do that. You have to do a lot of stuff to make it workable.

BTW-save the guide rails. They are hardened 3mm and good for motor shafts with a little work. Many motors use 3mm. The TowerPros do but they are REALLY soft metal and bend easily.

mescalinedreamz
08-30-2008, 04:03 AM
I have read though its simple, just unsolder the 3 and hook them up, this isnt correct?

jdetray
08-30-2008, 07:19 AM
You can run the CD-ROM motor by doing what you describe: Desoldering the three wires and connecting them to a brushless speed controller.

However, the resulting motor won't be powerful enough to fly any but the lightest and smallest of planes. In the original One hour CD_ROM motor thread (http://www.rcgroups.com/forums/showthread.php?s=&threadid=127606), Takao uses the motor on a very small flying wing. I doubt if it will fly the Lite Stik without improvements.

If you continue reading Takao's thread, you will see that better performance can result from re-winding the motor with thicker wire. Further improvement will result from replacing the weak ring magnet with 12 individual neodymium magnets. I've done all this, and it's very rewarding.

However, flydiver's recommendation of the GoBrushless.com GBv kit is a good one. The price is so low, it hardly pays to salvage parts from an actual CD-ROM drive (but keep those 3mm guide rails). The GBv kit will give you the experience of building a motor from CD-ROM-type parts, and the instructions are very good. Besides that, thousands of GBv kits have been built, so you can get lots of help and advice on the forums.

I have a GBv in a small foam Rare Bear. With a GWS 7x3.5HD prop and a 3S lipo, the GBv produces over 9 ounces of thrust. It should work great in a Lite Stik, maybe with a 2S lipo and a 8x4.3RS (slow flyer) prop.

- Jeff

ron_van_sommeren
08-30-2008, 08:57 AM
You have to remagnet the motor as Jeff said, for proper torque and power.

Introduction to diy motor building, must read. Several excellent articles on building lrk and cd-rom motors, pictures, winding diagrams, by Brian Mulder a.k.a. 'Mr DIY' on E-zone:
www.southernsoaringclub.org.za (http://www.southernsoaringclub.org.za/)
-> Articles from Southeasters
-> Electric Motors - part 1 ... part 5

Two cd-rom winding videos:
www.utahflyers.org (http://www.utahflyers.org/)
-> videos
-> instructions

Prettig weekend ;) Ron
diy motor building group (http://www.yahoogroups.com/group/lrk-torquemax)

mescalinedreamz
08-30-2008, 04:05 PM
http://www.wattflyer.com/photopost/showphoto.php?photo=3881&cat=500 thanks, I did find some wire, actually a huge roll that is the right kind.Its a little bit thicker. So im going to start reading and watching videos. I dont have the little magnets. ANy idea of where i can get those around the house? or inside something electric? I wish i could remember what this wire roll is from. It almost looks like part of a tattoo gun winding deal. But i know its not cause i recently seen it inside of something at a store. I just dont remember what its from. Its red coated wire. I will post a pic of the motor and the wire deal. http://www.wattflyer.com/photopost/showphoto.php?photo=3881&cat=500http://www.wattflyer.com/photopost/showphoto.php?photo=3881&cat=500

mescalinedreamz
08-30-2008, 04:21 PM
If i use the new wire with the old magnet, will it be faster? Also on the one hour cdrom picture, my motors stators go like this W U V Hu Hv Hw C 1a Then a stator with no letter, just blank. Just thought i would throw that in if its weird or something.

flydiver
08-30-2008, 04:37 PM
You said you were a hands on learner. Without info though your hands won't be very useful. Start doing some reading.
As stated, the motor ain't worth much in it's current configuration. It needs BOTH magnet replacement AND rewinding. AND other stuff to be useful in a plane. You will NOT find suitable magnets around the house, drug store, or hardware store.
You CAN find stuff at GoBrushless.com or some of the other motor links.
No, it will not be much more powerful just by re-winding. The only benefit you'll get from that is practice winding. But you'll need to do that anyway.

mescalinedreamz
08-30-2008, 10:23 PM
Well i did it, just the rewiring into a delta. It works and there are no shorts. I need to glue a prop adaptor to it though. I dont think its very strong though. I just hooked 12 volts through the esc from an ac/dc adaptor. I was figuring it would be faster and louder. But then again its nothing compared to this ammo 28-45-2700k i have for sale!

jdetray
08-30-2008, 11:17 PM
That's great that you got it running. I'm not sure I'd bother with a prop adapter unless you are going to rewind and re-magnet the motor. It won't be good for much unless you do both of those things.

- Jeff

GreenAce92
08-31-2008, 02:01 AM
Wait why go through all this trouble when your selling a brushless outrunner you already have? I would say just buy a cheap hobbycity outrunner i mean heck you could buy a 7dollar red motor that can fly a 20oz bird. much better than doing all this.

But great job for the effort and persistance!! :)

mescalinedreamz
08-31-2008, 03:06 AM
Thanks, but the motor i have(ammo inrunner) is way too big for the plane i have. The guy who sold it to me told me it could fit my pico-s. Yeah right. But im a noob and believed him. But it was a great deal and i wanted a brushless motor, I didnt care if it would fit or not. So i put a prop adaptor onto the little cd-rom motor and it will only spin the mini delta prop. It will not fly anything though unless i attached it to a bug.

flydiver
08-31-2008, 03:30 AM
Guess you are having those 'dreamz' again'.
Study first, buy once (maybe twice).
Ignore information > buy lots of times and never figure it out.
Grok that?

jdetray
08-31-2008, 03:47 AM
You can make a useful motor starting with the parts from a CD-ROM drive. I and many others have done it. A few years ago, it was just about the only inexpensive way to acquire a brushless motor.

But nowadays, the only reason to do it this way is just for the fun and challenge of it. You won't save any money, that's for sure. As we have all stated, it is much cheaper and easier to simply buy one of the many inexpensive motors that are now on the market.

- Jeff

GreenAce92
08-31-2008, 04:36 AM
I for one reccently rewired a 2409-12 outrunner, i guess i was either usin the wrong wire, or the bearings were just shot because she was hot! and i didnt even have a prop on her, i mean knowing how to rewire and knowing how it all works is great, specially if your trying to get max efficiency and power. But if ya want to just enjoy flying rc planes just buy some cheap outrunners.
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5482&Product_Name=FC_28-05_Brushless_Outrunner__1600Kv

mescalinedreamz
08-31-2008, 02:03 PM
Thanks guys for the input. I plane on buying those hobbycity ones. There are so many to choose from. I just dont know what i want or need. I really want a epp plane for crashes. But I dont want to buy a motor and have it not be able to fit. So unfortunatly i am going to have to start reading about all the diff sized motors etc. I put a 3s 3.7v at 640 mah a peice x3 of course into my pico-s with that small ips motor/gearbox. The batteries i bought on clearance from radioshack. They belong in a wii, very small and very light. WOW, what a difference. I always used 7.4v cell phone batteries around 3200 mah. and this 3s blows them all out of the water. My little plane would fly slow and stay level in the air. I am talking very slow. Before this 3s if i flew it slow then it would lose altitude. Full throttle it would go almost verticle. I made sure that i took breaks to let the motor cool off and only went full throttle one time for about 5 sec.
When someone said they used to use cd-rom motors. Did you rewire, put new magnets in for more power? Also if i did rewire and remagnet this cd-rom motor, what size prop should i use if i wanted it in my pico-s?

GreenAce92
08-31-2008, 03:17 PM
Really the way to choose is to know roughly your AUW(all up weight) so i mean if you plan on having a plane that weighs 20oz then your looking at a motor that produces at least 15oz of thrust(this is for a mellow flying parkflyer) and the KV's the faster they go the higher pitch speed is so you go faster but you have less thrust(so 3000kv is not for 3D planes) also you spin smaller props, and vice versa for slower kv. Also on one motor it makes a big difference wether your using a 3c or a 2c, see a 3c you will get much more KV but you'll have to use a smaller prop. What you gotta do is look at the specs, keep an eye on KV, amp draw, and a couple other variables(im still learnin about BL outrunners and such) and then make sure you have the right battery, Chellie said something like you take the mah times the c rating to get your amps that the battery can provide so if you got a 3c 1800mah lipo which has 20c(make sure you have a high enough C rating so your lipo does not get puffed) so you do 1.8(from 1800mah) * 20c which would gives you 36amps, so you gotta make sure your motor does not pull more than this

other guys please correct any mistakes i made as im just sharing what i learned but im not sure if its 100% correct i know i missed alot of stuff.

ron_van_sommeren
08-31-2008, 05:48 PM
... But nowadays, the only reason to do it this way is just for the fun and challenge of it. ...DIY motors or rewound motors have higher efficiency because you can do a better job at winding. Copper fill factor is better.

Vriendelijke groeten ;) Ron

ron_van_sommeren
08-31-2008, 05:51 PM
http://www.wattflyer.com/photopost/showphoto.php?photo=3881&cat=500 ... I dont have the little magnets. ANy idea of where i can get those around the house? or inside something electric? http://www.wattflyer.com/photopost/showphoto.php?photo=3881&cat=500Neither nor.
www.engconcepts.net
www.supermagnete.com
www.aircraft-world.com
www.gobrushless.com
www.innov8tivedesigns.com

Vriendelijke groeten ;) Ron

jdetray
08-31-2008, 07:34 PM
When someone said they used to use cd-rom motors. Did you rewire, put new magnets in for more power? Also if i did rewire and remagnet this cd-rom motor, what size prop should i use if i wanted it in my pico-s?
Yes, I did rewind and re-magnet my CD-ROM motors. To repeat for about the 4th time, you must do this to get enough performance for a typical small electric plane.

I recommend rewinding with 19 turns of #26 wire, with a Wye (not delta) termination. Re-magnet with 5x5x1mm N50 magnets (or 5x4x1 magnets if the 5x5x1's won't fit). Use 6x3x2.5mm ball bearings. With 3S lipo, use a GWS 7x3.5HD prop. With 2S lipo, try a GWS 8x4HD or a GWS 8x4.3RS (slow flyer) prop.

This assumes your motor is the typical 22.7mm stator size found in the majority of CD-ROM motors.

The wire, magnets, and bearings are available from GoBrushless.com (http://www.gobrushless.com/) or from Strong RC Motors (http://www.strongrcmotors.com/). Both companies also offer a $10 motor kit that includes all of the parts you need to make a motor.

- Jeff

jdetray
08-31-2008, 07:42 PM
DIY motors or rewound motors have higher efficiency because you can do a better job at winding. Copper fill factor is better.

As always, Ron, you are correct. A carefully made DIY motor may be more efficient than a similar cheap factory made motor. I was thinking only of cost, because so many inexpensive brushless motors are now available.

As you know, I am a big advocate of DIY motors. I think I own only one motor that I did not make myself.

- Jeff

Wrench66
08-31-2008, 07:45 PM
Really the way to choose is to know roughly your AUW(all up weight) so i mean if you plan on having a plane that weighs 20oz then your looking at a motor that produces at least 15oz of thrust(this is for a mellow flying parkflyer) and the KV's the faster they go the higher pitch speed is so you go faster but you have less thrust(so 3000kv is not for 3D planes) also you spin smaller props, and vice versa for slower kv. Also on one motor it makes a big difference wether your using a 3c or a 2c, see a 3c you will get much more KV but you'll have to use a smaller prop. What you gotta do is look at the specs, keep an eye on KV, amp draw, and a couple other variables(im still learnin about BL outrunners and such) and then make sure you have the right battery, Chellie said something like you take the mah times the c rating to get your amps that the battery can provide so if you got a 3c 1800mah lipo which has 20c(make sure you have a high enough C rating so your lipo does not get puffed) so you do 1.8(from 1800mah) * 20c which would gives you 36amps, so you gotta make sure your motor does not pull more than this

other guys please correct any mistakes i made as im just sharing what i learned but im not sure if its 100% correct i know i missed alot of stuff.

Good advise there GA, you're making all of us Renegades proud over 'ere :cool:
As a tried and true tinker'er, I have resisted rewinding these BL motors just for the time factor. Seems to use up a load of the day.
Since you can get some really strong motors from HC or the like, that are quite efficient and are under $8 it's harder to justify the time.

I am well and truly fasinated by it though still :<::ws:

Ray

mescalinedreamz
08-31-2008, 08:42 PM
Well, i think i will just buy a hobby city motor. Cheaper and no worries about shorting out an esc by rewiring myself. For now im just going to use a motor out of a battery powered dremmel. MY little ips pico-s motor died today, hobby shops are closed today and tomorrow. This motor spins this 1047 prop pretty well. Thanks for the help and sorry for the frustration.