Rewinding AXI with broken wire?

[Mod Man]

Hey Guys,

I accidentally damaged one winding on my brand new AXI 5345 outrunner.

How do I get it rewound?

Matt

[brushlessboy16]

your best bet would be sending it to axi or maybe sikeston3m could re-wind it for you.. up to him really

[Mod Man]

Hmm, Czech republic.

Not happening.

Matt

[What's_nitro?]

How did you damage it? How badly? If you post a picture I could advise more effectively.

[Mod Man]

Its a long story. But, two windings have broken wires.

Matt

[sikeston34m]

Originally Posted by Mod Man

Its a long story. But, two windings have broken wires.

Matt

Any chance you could post a picture of the Stator please?

What are you powering with this? The Bike?

I just got a pretty good deal on several AXI 4130 outrunners whose stators spun. This tends to rip the wires off the winding, break wires and all sorts of ugly things.

[Mod Man]

Yes, this is for the bike. I have another, so I am not down for the count or anything (the bike is just about finished by the way).

I will post a picture later today.

The windings are broken at the but end of the motor visible through the openings at the top of the can (screw up using needle nose pliers without being careful).

I know I can send it to Hobby Lobby for a replacement at 1/2 retail. That may be my best option. But, heck, if I can get it rewound, I would love to especially if I can lower the KV. But, even getting it repaired as is would be fine.

Matt

[sikeston34m]

Is it the 5345/18?

That's 171kv now.

What kind of amps do you plan on pulling?

If it's Lower kv that you want, the very same 18 turn Wye wind will yield 1.73 less kv, but 1.73 times the torque that you currently have.

That would be about 100kv.

What kv do you want?

[Mod Man]

It is currently a 5345/14. The KV is 225. I would love 100 KV.

Can you rewind this? What would you charge me for it?

How high voltage could I run through it? I may have a line through Castle on a Beta 90 volt ESC. But, no big deal if not. I am currently running 12S.

Matt

[sikeston34m]

Originally Posted by Mod Man

It is currently a 5345/14. The KV is 225. I would love 100 KV.

Can you rewind this? What would you charge me for it?

How high voltage could I run through it? I may have a line through Castle on a Beta 90 volt ESC. But, no big deal if not. I am currently running 12S.

Matt

The Biggest Problem is getting the Stator off the Bearing Holder. It's not just a little stuck, It's ON THERE! LOL

I don't know what the exact adhesive is that AXI uses, but it's some tough stuff. I posed this question directly to AXI and they told me it would release it's grip if it was heated to a temperature above 300 degrees.

So that's what I did, but the motor that I was working with, I had added some RED Loctite to the Endbell side of the stator. I noticed a little void, a little crack there where I could seep some more "protection" in.

I'm sure It would have been easier to remove if I hadn't have done that. 300 degrees in an oven later, it wouldn't even think of budging. It took 500 degrees and about 4 hours to get it off there. I could just barely wiggle it before it cooled enough to reset the adhesive. I almost tore it up.

500 degrees melted the coating on the old winding wires and "glued" them all together. It almost melted the coating that was on the stator and made it very difficult to rewind. The coating that is on the stator serves to insulate the stator from winding shorts. It also softens the sharp edges of the stator, so it's not so apt to shave the coating from the winding wires when they are being pulled.

I know you're really into RC and have alot of contacts for information. My Question to you is this, Is there an Adhesive Solvent that will help to break the grip without using so much heat that other damage occurs?

Once the Stator is removed from the Bearing Holder, Yes I can rewind it. It usually takes me about 5 or 6 hours to rewind one from this point.

I'm sitting here staring at a spool of 22awg winding wire that's rated at 200C. It's the good stuff. The coating doesn't melt until it reaches 392 degrees Farenheit.

I prefer to use the larger wire. It's a little harder to work with, but the end result is a motor that runs cooler and usually has a higher amp carrying ability than the factory ratings. It's also easier to come up with a greater Cross Sectional Area than the factory ratings thus more efficient and cooler running.

Why doesn't the factory use larger wire? Smaller Wire is easier to work with, easier on the workers fingers and easier to get a successful winding on the first try.

Can you tell what Ga. wire it's currently wound with? It's something like - 24 parallel strands of 30 awg wire for 14 turns.

Is there a thread here on your Bike? I would like to check that out.

It's not how much voltage you can run, it's how many amps your application will pull at the desired voltage. Operating Temp will determine the limits. If you intend to push it, consider cooling in your application. Airflow, and the heat sinking ability of Aluminum help tremendously.

Current Factory Wind is rated at 12S, and 110 amps for 20 seconds. We can bump that up some. How much, I'm not sure. This depends on the number of parallel strands of 22 Ga. wire that will fit for the number of turns that are used. (Stator Fill)

How much $ for this? Let me think about it. I won't choke you though.

[Mod Man]

Here is my build.

http://www.wisil.recumbents.com/wisi...er/default.htm

I am not sure what gauge wire it is. I could mic it, I suppose.

I am also not sure about the adhesive. I would have to do some research on that.

Man, I am in no rush what-so-ever. I am looking at $120 to pay Hobby Lobby for a new motor anyway. So, I know I have to shell out cash. I also know what it is like doing custom work for people.

I can PM you my number if you would like to talk.

I appreciate anything you can do for me. But, I am not hanging out in the cold. My new motor should be here in less than an hour. I have lots of time to have this motor rewound. ;)

Matt

[sikeston34m]

Congratulations on your build! I love it!

Some really great workmanship and planning!

As far as your motor choice being overkill. In the world of RC, most motors are designed with 20 to 30 minute runtimes in mind. IMO, overkill is good. It promotes efficiency and cooler running. Afterall, you won't be running it flat out all the time.

What kinda speed do you think it will do?

[sikeston34m]

Aaah, after reading more in depth about your build, I see it. 50 mph. Impressive.

In a very crude plaything I made, A Century 600 on 4000mah 4S carried me to 28mph. The run lasted for about 2 1/2 miles. I used a 1" rubber wheel that was spring loaded to make contact with a smooth front tire.

May I make a few suggestions?

If you're worried about over torqueing your driveline, think about limiting the amp draw the motor is allowed to pull. Or perhaps just install an Amp meter to help you keep an eye on things. If your belt slips much, it will wear quickly won't it?

If you have another motor, give it a try. It will give you a more educated guess on what KV is ideal.

[Mod Man]

How would I limit the amperage? I would love to do that!

Well, I got it running! It is raining today. But, between showers, I took it out for about 8 miles of riding. This thing is phenominal! I cannot say enough about it.

It runs 0 to 30 mph in under 5 seconds and that is only because I have to be careful with the throttle. Otherwise the main belt skips. If the belt did not skip, this thing would wheelie. It accellerates HARD.

I need to gear it up and fix (or reduce) the belt skip. Next I need to program in throttle ramp up (heli feature in my HV110). That will make it totally user friendly.

Matt

[sikeston34m]

I would fix the Belt to not allow for any slippage, then take it easy with the Burnouts! LOL

Can you estimate range yet?

Do you have a top speed "target"?