A Simple Rewind Question

[coldspot]

Hello-

I'm back to working on the Box Fan Mini Mill.

I liked the idea of a 10 Watt's for $10 Quest

So I'm going to give it a try.

I'm about to try to rewind this box fan stator

But, I'm wondering about the coils as far as

winding in a clock-wise or counter-clock-wise?

OR should I just make good notes on how it's wound

stock and try to follow that pattern?

I plan on using wire thats 0.042, salvaged

because thats all I have.

And doing a jerry/delta, so I know to hook the

coils straight across from each other in series,

and so on with the other two sets.

But am unsure about the coil to the right or left part?

(clock-wise or counter-clock-wise) looking down at coil.

So far as to the 10 for 10-

Free Box Fan Motor

Free Salvaged Wire

Neo's Disc's, (1/2"X1/16") @ $0.05 each, number to used unknown yet

Bearings to replace bushings for shaft, @ $0.99 Each two used

Hub plate using conduit coupler n box covers @ $3.50 complete

Free Blades using PVC.

Free bridge Rec's from computer power supply's

Thats all for now till coils get rewired

[ghurd]

They should be wound the same as the oposite coil.

Doesn't matter clock-wise or counter-clock-wise, as long as they are both the same.

Not a big deal if one is wrong, just switch the ends around.

If you are only after 10W, the factory wire will do that.  If the fan motor works. Remember to cut the wires that go deep into the coil so they are long. The other wire can be unwound a turn or 2 for length.

I have a feeling the slots will need to be 'full' using that large wire and small magnets.  If the voltage is too low, there is always star.

G-

[Jerry]

There is also doing 3 seperate bridges and wireing the DC outputs in sires.

Are there just 6 slots in this motor?

                        JK TAS Jerry

[coldspot]

Thanks ghurd-

Nope not after 10 Watts,

Hope to get closer to 75 Watts

But that will have to wait untill testing

can be done after it's up.

Have a plan on the magnets, using just enough

to saturate without over doing it.

Thanks jerry-

Yea just six slots

And I'll be using three little Bridge rec's

PS: great posts lately!!!

[kitno455]

ghurd had a 4 pole, 6-coil 3-phase unit. from the other re-wind thread on the front page we know that it's a phantom pole unit. i would do it that way, and jerry-rig it. maybe a series/parallel switch post-rectifier.

allan

[coldspot]

This is the project-





The stock coils, ends.





Brearings Vs Bushings

An easy mod with hand tools, (Files)





Done almost, Not so easy!

But should spin better and last longer

Will epoxy edges B4 assembly.

Thanks

Back to Re putting something in the winds

[kitno455]

it looks shaded pole- might want to cut the shading shunt before you reassemble.

allan

[johnlm]

That looks exactly like the same fan motor I used on one of my conversions (not shown in the diary post I did a couple of months ago).  I found that there were the same number of turns of each of the  original windings so I just connected the individual windings in parallel(a green wire and a red wire I think) and brought out the wires from each separate coil and then added about another 100 turns of #24 on each pole.  I then build a new rotor using the technique shown in my diary and put on 8 ea 1 L X 1/2 W X 1/8 thick neos and made it a 3 phase machine.  It was a bit tricky trying to get the cogging minimised on that motor.  The output V verses RPM is 30 RPM/Volt DC and it will put out about 30W at 1000 RPM in Wye connected configuration> I used a 3.25 ft dia TSR 4 prop on it.  I think there is around 250 turns on each pole.  If I were to do it over I think about 250 turns of AWG 22 would make it alot better.  As it is now the DC resistance of each pole is about 1.4 Ohms and the total output impedance in Wye mode at 1000 RPMs is about 10 Ohms.  Going to AWG 22 would lower this some.  If you are taking off the original windings I recommend cutting the copper shunts on each pole, and then reinsulate the stator laminates if you damage the rubbery painted coating on it.

As for the winding directions:  If you are going to make it single phase with 6 magnets on rotor and wind it with one continueous wire from pole to pole you need to reverse the winding direction every other pole so that all the poles end up in phase with with the alternating N-S-N-S-N-S magnet arrangement.  For versatility I recommend bringing out the two leads for each individual pole which will allow you to easily make it a single phase or 3 phase alternator just by changing the magnets on the rotor.  If you do this you may need to play around with the connections to get all the proper phasing unless you carefully label each lead with a start and end designation and wind them all the same direction.

Hope that helps

John

[Ungrounded Lightning Rod]

If you are taking off the original windings I recommend cutting the copper shunts on each pole, and then reinsulate the stator laminates if you damage the rubbery painted coating on it.

You don't lose much if you just make a gap in each shunt and leaving the wire in place through the core, compared to actually removing it.  You can probably do that without damaging the laminate coating.

[johnlm]

I have also cut the shunt on motors where it was accessible to do so.  On this particular motor the shunt is burried under the thick rubberized paint that coats all but the pole faces, so the coating has to be damaged to cut it.  On this one I tried to open it up by drilling it in two down through the slot in the face of the pole with a bit size that just fit the slot gap size but Im not sure if I totally opened all of them all the way up.  I have briefly tested some with the shunts in place and have ot seen a big problem, but since the shunts more or less short out about 20% of the pole area I suspect here is some amount of loss, and likely some amount of additional cogging if they are left in place.

Johnlm

[coldspot]

"shunts"

What a pain in the rear to try to

undo!!!

Do these just need to be cut on one side?

I've tried to dremel wheel cut just the one

side, (The one thats covered with wire when wound)

Not working very well, trying to cut deep enough to see

that the copper is cut thru.

I've also tried to cut the top off, then it looked

like a square copper piece.

Are these just a flat copper buss slid into face

slot then wrapped around to connect the ends?

Forming a "loop"?

If so, then just cutting connection, opening up the "loop"

would then "un-shunt" them ??

If said flat stock is just slid into slot on face, drilling

into said slot should open the loop if bit was sized

enough to reach each side of the slot and drilled to back-side.

If that is enough open it, one could drill at an angle thru

slot so as to be able to get the bit and drill head to

line up enough to go in and thru to open shunt up.

 Now wih this one I'll need to re-seal the lam's

after I've drilled and or ground into them in many

places, I hope epoxy is good enough, I have some.

Maybe if girlfriend has any more "Clear" finger-nail polish

I can talk her out of, I'll use that. Last bottle didn't

last very long. Used to seal extra mounting holes in

ceiling fan blades, (weather proofing).

I know there is ton's of stuff that is better to use,

but that I would need to "BUY" and I'd rather spend

money on better stuff like magnets.

lol