25mm 12 pole stator insulation

[dgaines]

I seek advice on the insulation of these 12 armed stators. I tried dipping them in an acrylic varnish. When dry the coating looked uniform, but after winding all three phases had shorted to the stator.

Don

[Q]

The biggest problem is at the top and bottom of teh stator. I have seen people using a piece of cardboard the same shape as the stator and use that on top and bottom. You can also use some very thin teflon foil in between the teeth. That way the whole stator is insulated from the windings. This kind of insulation is used in the TorqueMax motors.

[ScubaSteve]

Hmm those buggers are really that big a pain in the neck? We'll have the insulated 25mm 12-pole stators on the website in a few days... I was hoping to move most of the uninsulated ones at first, but hopefully folks will take my suggestion of just using the insulated ones as the TOP and BOTTOM stator in their stack.

[Air Mover]

Steve I use over cut heat shrink tube.. black from radio shack .. this is a 3stator stack for the 1X flux ring and 5X4X.9 mags.. I allow over hang to help protect the wire as I wind . :D :lol: :wink:

[Q]

Hey, that's a very neat idea!!!

Now, why didn't I think of that?????

[swatson144]

I just used it! spent the day on the machines and here's what I got. 25mm 12 arm 5stack 14pole 4x10x2,

Motor Rotor Calc (http://www.gobrushless.com/testing/motor_rotor_calculator.php?Stator_dia=24.98&Rotor_dia=29.56&Mag_width=4&Mag_thick=2&num_holes=5&FS_airgap=0.1541&dim_holes=5&num_poles=14&submit=Calculate+Now)

I'll have to figure out how many turns I want and wind it up tomorrow.AacCBbaACcbB

[Q]

Looking good!!!!

[Air Mover]

Thus far I have found
12T 24g easy
13T work

20T 26g easy
22T workout to maintain just two rows.

4coils per phase doesssss make a world of diffrence in every way..

you will find yourself using delta to get higher rpms....as the 4th coil really takes down the top end...

may try a wye 10mag.

thus far 14's /16's delta. 8)

[swatson144]

It looked good on paper but didn't work out so well in practice. I went to time tested combination of a wrap of unwaxed dental floss and nail polish. I used 3/8" shrink tube that had to be stretched over the 5 x stators. when shrunk the thickness of the stuff was too much, and it tended to roll off the corners and get in the way actually making it hard not to nick the wire. I have some of the radio shack tube but it is all too small though much harder. The only HS tube I had that would fit was a lot more rubbery. YMMV

[Air Mover]

you can leave the heat shrink longer past the tooth to avoid rolling ...then trim once you have all your wire in place.. :D

[Air Mover]

:)

[hubgar]

@ Air Mover. Where did you find the 5x4x.9 mags? I too am working on the 25mm 12pole stators and the 1X flux ring. I can't seem to locate any.

Hubert

[Air Mover]

Just use the one George sells.. 5X5X.9 then bevel the bottom edge so the mag lays down flater will act like a 4.8/4.7mm mag and give you the clearence for that just right air gap.

[hubgar]

Thanks Air Mover. Will do.

Hubert

[Air Mover]

http://www.engconcepts.net/List_Of_Motor_Magnets.asp

[DadHav]

Hi guys, It looks like Steve is solving the insulation problem for us. I've tried most of the above methods but settled into something a little different. I round the sharp corners of the stators then coat the wraping area with black CA. So far I haven't had any shorts. This is careful work though with the stators. Below is a few pictures of a filed stator and my most recent motor made with GB 25 mm stators and magnets. This also gives me a chance to show off my flux ring made from the tubing material that Mr. 144 recommended. I'm hoping steve will come up with some larger stators in the future also. Man, Is this a lot of fun or what?. I'm wondering if I'm gonna be building motors all winter or if I might also get to a plane. Oh, I forgot to mention: This LRK style motor is a Tsunami Mommy.
Thanks everyone for all the great ideas. I gotta take some time now to read Lucien's posts.
John

[Air Mover]

Very nice machine work well thought out and nice motor build...

I dont shrink it tight.. and then wind without pulling tight down on the wire.. I just lay it in neat on the first row and avoid pulling tight again on the second level.... I use the newbie wire .. thus far no shorts..

[DadHav]

Hi Air Mover, Thanks for the compliment. I usually mount the back end bell to the firewall then install the stator and bearing holder, tighten the set screws and put the rotor on. This gives a nice looking installation. I understand what you're doing with the windings. I found winding to tight could be a problem also. I started winding motors with the colored wire for tests, then when I was satisfied with the number of turns, I wind the last time with 3 or 4 strands of #30. I like this for the reason you are talking about. The windings can go down without pulling to much on the wire. I also use a broken wooden prop or sanded popsickle stick to push the wires up against the legs, This actualy gives a little more room for the next phase.
Happy Motoring
John

[Air Mover]

Hey for those wanting to use the GBX flux rings these N50 class mags should make it easy..there from George's site.. Has anyone else come up with a better way to insulate these 25mm stators?

otor Magnet M0520 5mm x 5mm x 0.75mm magnet for brushless motors N50 Nickel Up to 49 for $0.25 each From 49 to 499 for $0.2 each Over 499 for $0.15 each


I know .75mm mags seem like a waste of time.. but the 1mm N50s I have used work well along with the N48's 0.9mm...but requires beveling the edges down to seat the mag for a useful air gap.

[Jay C]

I just used it! spent the day on the machines and here's what I got. 25mm 12 arm 5stack 14pole 4x10x2,

http://www.gobrushless.com/testing/motor_rotor_calculator.php

I'll have to figure out how many turns I want and wind it up tomorrow.AacCBbaACcbB
Calc only works for 9-tooth 22.7mm GBx motors (for the moment) until I get more 12-Tooth data to analyze.

Send me your Volts, Amps, and RPM readings for noload and several different propellers at WOT only please. I'll add the 12-T stators when I'm confident of the constants :)

Jay

[swatson144]

By "just used it" I was talking about the shrink tube insulator method. Though that didn't pan out for my use later. I wrapped wtih unwaxed dental floss and nail polish 16t distributed for 14 mags. Clicking the link would take you to the rotor calc for that motor, as it is easier than listing all the data. You got motor calc on the brain :?: :lol: The motor is now wound and ready except finish reaming the shaft hole and I'll gladly suply you with data as I get it. I am intentionally leaving the wires long (about 3")so I can change it to delta after testing wye. Is there any props you have good constants for now, that you'd prefer to see? I have mostly APC SF and TE in the larger props. I also need to find some reflective tape for the no load speed.

[Jay C]

You got motor calc on the brain :?: :lol:
You got that right ... I need to take a break from it ;)

[hubgar]

Steve, where are those 25mm 12-pole insulated stators you mentioned above. I don't see them on the site yet. I could sure use some!

[Happy|Harry]

here's a pic of some vac formed insulators a friend did for me, i've yet to try them out but i can forsee no problems, but with the insulated stators coming soon all these ideas will be defunct lol

phil

[dgaines]

Folks, thank you for all the help. Using your input I find that streching ~ 3/16" shrink tubing worksvery nicely. I also put a little tiny drop of epoxy to cover the bottom edge of the slots. I also found that I feel more confident if I spend some time sanding all the sharp edges on these stators with 400 sandpaper before the above treatment. I look forward to the pre-insulated stators.

Another winding point to be aware of is that winding on the 25mm 9 pole insulated stators requires much care and monitoring if one uses the wire from Radio Shack. Said wire in the 30awg size, the only one I have used, shorts to the stator very easily. Be aware of this if you use such lightly insulated wire.

Don

[swatson144]

Steve, where are those 25mm 12-pole insulated stators you mentioned above. I don't see them on the site yet. I could sure use some! YES Please! once you wind the uninsulated. There is no warm fuzzy feeling when dealing with the terminations. the sharp edges are still on the hub and it is near impossibele to cover that area, which is right where the starts are forced to live no matter which method of covering them one uses!

[Felix]

YES Please!

Is this what you're looking for? :D

http://www.gobrushless.com/ccp51/cgi-bin/cp-app.cgi?usr=51F4778569&rnd=4382505&rrc=N&affl=&cip=24.73.166.246&act=&aff=&pg=prod&ref=S-250-22-12I&cat=stators&catstr=HOME:stators

Looks like they went on the GB website today.

Felix

[swatson144]

Just finished my order~! I was waitin on them,

[ScubaSteve]

Um... 25mm insulated 12 pole stators are up. :oops: :wink:

[swatson144]

I just ordered some...Now I can get on with testing without the fear of smelling smoke! Thanks. I hope my "weehooHOO" shout didn't scare the neighbors! They are from new york and a little different from others in these parts. :wink:

[ScubaSteve]

Hahahaha :lol:

[mintloop]

Hi,
The insulated 25mm stators are now available. :D :D :D
Gil