32mm outrunner!!

[airmcn_3]

Hey guys, I have a 32mm Stator with bell that is currently turning a 9x3 prop. putting out around 27oz of thrust. My question is the Bell is made out of some type of composite plastic material. Has anybody seen or heard of anything like this??? If so are there any advantages/disadvantages to this type of can/bell. Thanks Chris. Ill post pics later

[ImaBiggles]

Hey guys, I have a 32mm Stator with bell that is currently turning a 9x3 prop. putting out around 27oz of thrust. My question is the Bell is made out of some type of composite plastic material. Has anybody seen or heard of anything like this??? If so are there any advantages/disadvantages to this type of can/bell. Thanks Chris. Ill post pics later

Non-ferrous bells do not carry the flux as a black iron bell will. I expect its a lot lighter though. What kind of efficiency are you seeing now?

[airmcn_3]

Not really shure. as I am pretty new to building motors. I ushually took the easy rought and bought a built one. Anyhow here are the pics. The small motor is a 20mm stator for size refrence. Thanks Chris

[latrans]

Hmmm ........... this reminds me of something that I've seen before. Where did you get this motor, or more to the point who built this motor?

Latrans

[ImaBiggles]

Hmmm ........... this reminds me of something that I've seen before. Where did you get this motor, or more to the point who built this motor?

Latrans

Why so cryptic, if you think you have some info, why not give it?

[KenSt]

Is there any evidence of a band of steel molded in underneath the magnets? The picture is too fuzzy to see. Since non-ferrous metals do NOT conduct flux at ALL, there must be something there. :confused: I don't think the motor would be capable of such perfomance without it. If there isn't, :eek: the magnets would have to be so thick :eek: that any weight savings from the lack of steel would be lost.

(See also, "too much magnet thread")

[airmcn_3]

Well This motor came straight from China. I work for a RC company and this was somthing diffrent they sent me to check out. To awnser some of your questions. There is a metal ring behind the mags. The Mags are epoxied in on top of the metal ring. Thanks Chris

[latrans]

Why so cryptic, if you think you have some info, why not give it?

I didn't mean to be cryptic, I was just trying to be, uh, discreet. Nothing of great importance and not relevant here. Its a moot point anyways as airmcn-3 told us that the motor does have a flux ring.

Latrans

[airmcn_3]

In my honest opinion I dont like it. It seems heavy and fragile. I was not shure why they made it out of plastic so I figured I would ask you guys who know what the hell your doing when it comes to building motors. Thanks Chris

[latrans]

In my honest opinion I dont like it. It seems heavy and fragile. I was not shure why they made it out of plastic so I figured I would ask you guys who know what the hell your doing when it comes to building motors. Thanks Chris


There's no two ways about it - they made it out of plastic because its cheap. I don't think I'd spend my money on one, plus 27oz of thrust from a motor that big isn't alot, unless the watts in are pretty low.

Latrans

[airmcn_3]

Yes I totally agree, as I said it was sent to me I did not spend any $ on it. When I recieved it I looked at one of my buddies and said man I can get more thrust out of a double stator, Point being that this giant thing is crap. Now that I have it I think I can turn a new can for it, the question after that will be what kind of winding for a big prop, I would like to use this Stator for a Mini Katana. Any suggestions?????? Thanks Chris

[latrans]

Yes I totally agree, as I said it was sent to me I did not spend any $ on it. When I recieved it I looked at one of my buddies and said man I can get more thrust out of a double stator, Point being that this giant thing is crap. Now that I have it I think I can turn a new can for it, the question after that will be what kind of winding for a big prop, I would like to use this Stator for a Mini Katana. Any suggestions?????? Thanks Chris


Depends on how big a prop we're talking about. I built a motor from a hard drive stator and the bell from a cooling fan that produces 40oz of thrust with a 11x4.7 GWS SF prop. Its 10t delta in the distributed LRK (which I suppose means that its really 20t delta but it has 10t around each stator arm). The stator I used was 28.5x10mm so I think that 10t delta in the D-LRK scheme and 14 magnets would be a good place to start. I would also advise that you look at www.powerditto.de for more info on choosing a wind. Lastly I would think long and hard about what you think the quality of your stator is. If the laminations are thick and/or they are made of poor material then you will be wasting your time. If you can post a good pic of the stator and tell me how thick the laminations are I could propably tell you if its worth the bother.

Latrans

[airmcn_3]

Depends on how big a prop we're talking about. I built a motor from a hard drive stator and the bell from a cooling fan that produces 40oz of thrust with a 11x4.7 GWS SF prop. Its 10t delta in the distributed LRK (which I suppose means that its really 20t delta but it has 10t around each stator arm). The stator I used was 28.5x10mm so I think that 10t delta in the D-LRK scheme and 14 magnets would be a good place to start. I would also advise that you look at www.powerditto.de for more info on choosing a wind. Lastly I would think long and hard about what you think the quality of your stator is. If the laminations are thick and/or they are made of poor material then you will be wasting your time. If you can post a good pic of the stator and tell me how thick the laminations are I could propably tell you if its worth the bother.

Latrans


Very Good! Thank you for your info. I will take a better pic to show, I can tell you that the Stator is made up of 8 laminations, they look to be pretty thick. Agian thanks for your time. Chris

[latrans]

8 laminations? Wow, they must be thick. If that is the case I would have grave reservations about investing anytime in building a motor around that stator. The hard drive stator mentioned above had about 34 laminations, 0.3mm each. Your laminations must be about 0.625mm.

[flieslikeabeagle]

I know next to nothing about winding motors, but the plastic can concerns me as to how well it will hold up at high revs (lots of force on it as the little magnets do their best to shoot off in a straight line and the can wall has to persuade them to continue to move in a circle). An exploding can that shoots rare-earth magnets like shrapnel sounds pretty scary. :eek:

There is also the durability issue - what happens in a minor crash where the bell impacts something hard? I'm guessing a shattered bell, and a throwaway motor...

-Flieslikeabeagle

[airmcn_3]

I know next to nothing about winding motors, but the plastic can concerns me as to how well it will hold up at high revs (lots of force on it as the little magnets do their best to shoot off in a straight line and the can wall has to persuade them to continue to move in a circle). An exploding can that shoots rare-earth magnets like shrapnel sounds pretty scary. :eek:

There is also the durability issue - what happens in a minor crash where the bell impacts something hard? I'm guessing a shattered bell, and a throwaway motor...

-Flieslikeabeagle


Yes probably will not hold up.