Need 25mm 9 arm stator Info

[Rick Hodges]

I have decided to jump into building a 25mm stator motor after great success with a GBv. To keep things simple I am using the insulated 25mm 9 arm stators stacked 10mm thick. The bell is completed and has 12 - 10x4x2mm N50 magnets arranged NSNSNS. The air gap is 0.2mm. I intend to wind it ABCABCABC. (you will notice that the magnets and winding pattern are the same as the GBv instructions keeping it familiar).

I'm thinking of winding this with 12-14 turns of 24awg. My hope is that it will turn a 9x5hd, 10x4.7, or 10x6hd GWS prop (maybe bigger?) to develop 25 oz. + thrust on 3s while drawing no more than 12-15 amps. This motor is destined for a 15 oz. 3D biplane.

Am I on the right track?

I am new to this whole motor building thing and find it facinating. However I'm more of a mechanic than an electrical engineer. When I read all the numbers Kv Io Rm xyz etc. my eyes glaze over. I'm trying to get a handle on it but, WOW!

Just a note for the do not do list. After completing the bell and gluing the magnets I decided that instead of painting the steel of the bell I would blue it. I dutifully chucked up the assembly in a lathe and proceeded to blue the metal. This process requires carding with steel wool. WHAT WAS I THINKING? Don't do it. I sure thank whoever it was who posted cleaning up with a sticky putty. My bell was chock full of steel wool hair.

Thanks for your input.

Rick

[latrans]

I think that sounds about right. I know that a 22.7mmx 10mm GBX with the same magnets,winding scheme, wire and # of turns will produce close to that amount of thrust on a 10x4.7 prop so the 25mmx10mm should be better. Let us know how it turns out.

Latrans

[swatson144]

Hello Rick, I have no data on that specific motor but experience and my gut tells me you won't be disapointed.

[SkyCobra]

Rick

I have 25mm 9 arm GBL stators, 12 mag poles with .16 airgap
Just to give you more data to look at. My power supply tops out at 15 amps, so I don't have the numbers for top end stuff.

Turns AWG Magnets Prop Volt AMP Thrust
14 26 WYE 12 10x5x1.5 N50 9-5 12.0 5.2 16.0 6 GBL stators
17 24 WYE 12 10x5x1.5 N50 8-4 12.0 6.3 16.0 6 GBL stators
17 24 WYE 12 10x5x1.5 N50 9-5 12.0 9.2 20.0 6 GBL stators
21 24 WYE 12 5x5x1.5 N50 8-4 12.0 6.2 16.5 3 GBL stators

Have fun building !

[Rick Hodges]

Thanks for the input guys. I'm going to try 13 turns of 24 awg. Wye. I'll let you know how it turns out. I've been delayed. I burned out the switch for my lathe and have been rewiring the thing with a blasted Chinese wiring diagram.

Rick

[Rick Hodges]

We have a winner. :D

I built the motor 25x10mm 9 arm stator, 12 10x4x2mm magnets NSNSNS, air gap .18mm, 13T 24awg Wye. All up with 3.5mm connectors, mount and prop saver it weighs 53g.

Test resultswith fresh E-Tech 1200 3s:

GWS 9x5hd- 5 amps. 7110 rpm 16.1 oz thrust (calculated)
GWS 10x6hd- 7.2 amps 6150 rpm 16.37 oz. thrust (calculated)
GWS 10x4.7- 8 amps 5640 rpm 19.6 oz. thrust (calculated)
GWS 11x8- 12.2 amps 5000 rpm 27.72 oz. thrust (calculated)

I want to try a GWS 11x7hd to see where it will fit in. Overall I'm quite happy with the results.

Rick

[ScubaSteve]

Rick,

Perhaps a picture? :wink:

[Rick Hodges]

For Steve,

Pictures of my motor. This is the second motor I have done. The first was a GBv 1.1.

Rick