KDE4012 400kV Windings, Good/Bad?

[zavycq]

I just received my order of eight KDE4012 400kV motors and the first one I opened, the copper windings look to be kind of sloppy. So I opened a second one and looked at it, this one looked better. The one on the left is the first one I opened that looked sloppy, the one on the right is the second one I opened that looks better.

My question are:

1. Is it safe to operate the sloppy one?
2. Will there be a performance loss on the sloppy one?
3. Are there any downsides to sloppy one?

Here are some additional photos of the motor in question:

 

[zavycq]

KDE responded very promptly:

Unlike the motors you are used to seeing on the market, the KDE Direct XF series are hand-wound and as such, will not be as “neat” as the lower-cost motors that use machine-winding techniques. The reason for the hand-winding is to increase the copper-fill into the stator, which cannot be done with machines – yields far improved performance and efficiency to do hand-winding, but is more expensive and much more difficult.

In terms of performance degradation, there is no negative-effects of this and the entire winding-bundle is epoxy-bonded and oven-baked, locking all the windings together as a single unit to prevent issues. No concerns, the higher-copper concentration far outweighs and benefits the overall performance of the motor than matching perfect windings by machines.

If you want to see more of the internal details, please feel free to check out the video on YouTube discussing the design aspects:

https://www.youtube.com/watch?v=CkRo5FeXcwc

 

[Fat Corgi]

I am looking to purchase exactly the same motors, so will be keen to hear how you find these ones. Are you running them with the KDE esc's?

 

[Motopreserve]

I am looking to purchase exactly the same motors, so will be keen to hear how you find these ones. Are you running them with the KDE esc's?

I have just put these same motors on my new hex build. I noticed the windings also, thanks for posting the response.

I have only done 3 quick test flights so far, using the 4012XF matched with the 55A ESC. So far, so good. Smooth and quiet to my eyes/ears. I will be getting some more testing in once the weather clears, which in Vermont is looking like next spring

 

[zavycq]

I'm using the 80amp ESCs by T-motor. I am planning on having an alternate set of booms with T-motor U7s, thus the high amp ESCs.

 

[Motopreserve]

I'm using the 80amp ESCs by T-motor. I am planning on having an alternate set of booms with T-motor U7s, thus the high amp ESCs.

Good call. I've read a few things about running the U7 with other ESCs than the 80A and it seems to cause problems. No harm having an ESC that is above and beyond the needs of the KDE (other than a little weight maybe).

 

[min0nim]

Any specific reason for the 55a ESC's?

When I was running my build through eCalc, the max per motor was topping out at about 24A continuous. Even with 18" props, the max current was about 32A, at 100% throttle.

Just curious...and hoping I haven't overlooked something!

 

[Motopreserve]

Any specific reason for the 55a ESC's?

When I was running my build through eCalc, the max per motor was topping out at about 24A continuous. Even with 18" props, the max current was about 32A, at 100% throttle.

Just curious...and hoping I haven't overlooked something!

The 35A was out of stock and I was impatient But I figured that the slight increase in cost would give me MORE than enough headroom and possibilities for the future...