Scorpion 2221-10 3000KV Rewind

[Bladecpnitro]

I found the short.
I new it was on the red wires 3rd phase and with the megger hooked up to the red lead I unwound the 3rd tooth of the 3rd phase until I no longer got a reading of zero. I repaired the bare hammer and wire with fingernail polish.

I rewound that tooth and checked after each turn and found a short once more and repaired it. Now I'm ready to do the ESC test.

What I couldn't remember about the megger is that a reading of zero is a direct short. Also L E are the connection points. The directions are pretty vague on the VC60B almost useless.

I tell you what I'm ready or fall. Its too hot to enjoy flying right now.

[Bladecpnitro]

I went ahead and ditched the thin stranded wind and started with the .85 wire.

I kept getting a short to the stator on the same tooth I had a problem on with the thin wire.

So now I have 2 phases wound with .85 and paper. With the paper I can't get but 5 turns though.

I guess if I'm gonna use paper I should really strip the stator or repair the stator.

I did repair the stator actually but the epoxy flaked right off.
I didn't strip it down completely but sanded it so epoxy would stick.

[1BOHO]

to do the last turns you will have to thread them versus pulling them around the teeth. Stagger them similar to the pyro in my signature.use and old plane prop or credit card to flatten the winds against the iron. Look closely and I bet you see the holes you can thread the last turns through. Take your time it's nothing to prove for the forum so take all the time you need. You can lay one as deep as you can between the hammers and secure them with uhu. The nail polish wont hold up so u will need some epoxy. File the ends of the wires to a point and remove the sharp edges so you can thread them. I have even use lubricant so the wires will slide.

[Bladecpnitro]

I think I had a chance of getting 6-5-6 turns without the paper. Its everything I can do to get 5 turns with the 5 mil Nomex paper.

Its .127mm thick

[1BOHO]

Take a photo of what you got so far

[Bladecpnitro]

I've taken it all apart now to repair the stator and do away with the paper.
I didn't like the paper on this little motor. I threw some engine paint on the chipped area's. That should work shouldn't it?

I think I've been pulling the wire a little too tight so I made a few practice winds to work on my technique with this small motor.
This wire may be closer to .87mm. Its 20 aug wire and everywhere I look the metric size seems to vary.

I cut 12 - 1" long pieces and put them all in a slot and they pack the slot full as it can get. Here is a pic.


I don't think 6 Turns side by side is going to work with this wire size I could do the 5 or an easier wind might be to do 4 and terminate Y for 2481 KV and go up a pinion size.

With the perfect wire size 3-3-3 Y would be cool. I have some 1.4mm wire but only 4 of those will go in the slot.

[1BOHO]

Step down to 21 ga.

[Bladecpnitro]

I'd have to order it. I can live with a 5-5-5 winding. After all thats what its had on it minus one tooth having 4 turns for two years.

I almost have 2 phases complete at 5-5-5 turns with no short's. I'm not pulling the wire so tight and taking it slower and using the pliers this time where I can. I didn't originally think I could use the pliers on this motor so didn't bother but they do help a lot to flatten the first 4 turns.

[Bladecpnitro]

One post to go. I just checked and there are no shorts. I'm done for the night. The last phase is the toughtest as the wires are more crowded from crossing wires.

I hate to sound like a safety nut but do you ever feel like you should be wearing eye protection while winding a motor?

[1BOHO]

Originally Posted by Bladecpnitro

One post to go. I just checked and there are no shorts. I'm done for the night. The last phase is the toughtest as the wires are more crowded from crossing wires. Attachment 662528

I hate to sound like a safety nut but do you ever feel like you should be wearing eye protection while winding a motor?

I can't speak for anyone else but I don't think about it even though if you are not paying attention you could poke yourself in the eye? Hope that is not what happened.

[Bladecpnitro]

No I didnt' get poked in the eye its just a scary thought so I got out my clear saftey glasses. LOL!

Anyhow, I have a master piece wound! To some of you it may seem some sort of paper weight as it is but I'm happy with it.

These little motors are hard to single strand wind in their own way as the bigger ones are. The wire is much easier to bend but still each strand has to go as perfectly as you can get it so the rest work out.
I like to get that first wire all the way inside far as it will go and flattened out, then wedge it in place with wood before making each half turn and do the rest the same way. Its a shame I figured that out towards the end of the wind.

I learn a little better technique each time I wind and I'd probably do this one better if I did it one more time but it has no shorts and I feel like its worth a go.

Now if I can just get the motor base mounted without creating a short. I seem to have misplaced the stock hi temp plastic to cover the top of the motors. Maybe a layer of Kapton tape will suffice or Nomex paper?
Here are some pics.


I went ahead and baked the Corona varnish on as well.

[1BOHO]

Cool! Well let us know how it runs? I assume we are not here alone. Looks nice


1 b.rother o.n h.is o.wn


Its hot enough here to just let it cure outside

[Bladecpnitro]

Hey I got it capped off with no shorts. I was worried about that a little. My dowell wasn't quite wide enough to space the wire away from the base plate but it was just enough with the glass tubing to help insulate. Plus I cut a new round Nomex paper with a hole in it that fit the bearing tube perfectly for extra protection.

I put it in my wood vise instead of pushing all the wires in the bottom hard into the stator to get it together and tapped it with the wooden end of a ball pean hammer until it was seated all the way.

I'll post some more pics in the morning I have to crash!

[Bladecpnitro]

I got the motor all put back together and ran it in the drill and one phase shows half the ac voltage the other two have.

The only thing I can think of causing the issue is the way I hooked the motor up so I would have just a little longer leads.

I hooked it up as follows

1 Start A to end C
2 Start B to start C
3 -End A to End B

I need some better solder and cleaner. My solder doesn't take to well to single strands especeially if I don't twist them up and I didn't particularly want to twist them up.

[1BOHO]

https://www.helifreak.com/attachment...8&d=1454780534

If it is 200*C wire you will have to remove the insulation exposing the bright shiny copper for the solder to take. I use silver solder or rosin core electrical solder and you heat the wire not the solder. I gently scrape if off with and exact-o knife and make the leads as short as will work. You have two starts and two ends hooked up together That is incorrect for delta it should be the start of one phase to the end of the adjacent other all the way around and the 2 conductors of each will make U,V,W motor terminals.

[Bladecpnitro]

I thought I had read somewhere that it would work hooked up start of a phase to a start of another, should have know better but I had to try it.
LOL! Live and learn.

I'll fix it right quick this evening.

[1BOHO]

A wye configuration consist of all the ends of each phase bundled together and each start as the U,V,W, motor terminals. With this motor I guess you could have done a 3 deltas Paralleled wind.

[Bladecpnitro]

Well I finally have the motor apart again. I went ahead and built a small bearing press with a truck jack I had laying around. It works effortlessly along with the stator vise and push pin that a turned down to a slip fit the other day. I know I could have tapped it out with a hammer a hundred times by now and could have it fixed possibly ruining the bearing possibly not.

I didn't do that and I waited until my press was finished so I could use it. LOL The reason I wanted a press is because I can literally push that motor apart with the bearing in there a hundred times and never hurt the bearing. And I can do it with all Helicopter motors now. Am I dumb? Nah!

[1BOHO]

Nice idea. Did you get the motor terminated correctly? What was the running Kv?

[Bladecpnitro]

Yes I just finished testing it.

Drill Test - 3424 KV

ESC Test at 12.36V YEP 45 ESC- 100% throttle = 3438 KV

pulling 4.09 Amps

IR - .02 ohms

Copper Increase - I can't think how right now to figure the copper increase but the stock 13 strands of .21 is .45 sq mm.My single .863 according to Techfix is .584 sq mm and stock was 5 turns on both so what % increase in wire did Johny have?
I have no clue?


How bout this ......... .584 - .45= .134 difference
.134 / .45 = .297% increase in copper
Is that right?