Rewind of Box Fan Coils

[coldspot]

For the other "small Builders" out there.

I'm ready to rewind a Box Fan stator

6 poles

The wire I salvaged is # 18.

Being that I've never done this before

I wonder if I should just put as many as

I can fit or is there a "Good number of turns"

to try?

Neo's to be used will be the little ones

I got, (Half" by 16th")

One rotor will have six around it, (one deep)

Other rotor will have 4 around it, (two deep)

I'll leave the coils start and end wire seperate

and out of it for trying different hook-ups.

The salvaged wire is 18

Also unwinding a transformer that had two in hand #18

Also wondering if I should try a two in hand on it?

The stock coils are=

3 wires

two #26

one #28

THANKS for all the fun

 

[johnlm]

Hi Coldspot

That is what I did - wrapped as many turns of #18 as I could get on each coil, and I was able to get 100 turns in each coil without working very hard to make sure the turns were nice and neat to reduce lost space amoung the wires.  Used 1 X 1/2 X 1/8 inch Neos on the rotor 6 each to start and had to slant them quite a bit to reduce cogging.  I later used 2 each of these neos for each pole, 12 total and got quite a nice output out of it - can get 40 to 50  watts out of it pretty easily with a 4 ft prop.  I highlighted this conversion in the diary section about a month ago titled "box fan conversion".  On another conversion I brought out all the (6ea) separate coil leads which was wound with about 235 turns per pole of #24 wire.  I ended up making a 3 phase (Wye connected) unit out of it using 8 of the neos mentioned above.  It works pretty slick also as the 8 magnets on the 6 poles helps reduce the cogging.  I think I can get about 30 to 35 watts out of that one using a 3.2 ft prop in a 18 mph wind.  The trick I have found with these box fan conversions is to try to get the output voltage in the range of 25 to 35 RPM/Vdc which fits up to 3 to 4 ft (TSR around 4) props pretty well to provide for 12 V cutin in the range of 6mph wind speed.  I use one of these box fan conversions to keep the 115 AH battery on my camp trailer up in the mountains charged up for my visits on weekends.  The wind up there doesnt exceed 15mph very often so I get about an amp or 2 typically when the wind is blowing, and its about right to recharge the battery during the week after a typical weekend's usage.

Have fun

Johnlm

[ghurd]

Seems like 140 turns showed up a few times while calculating for 3 phase 4 magnets.  

That was for delta Jerry OR star, then I'd try different blades to see what worked best later.

Also, that was with a lot larger magnets.

Have you thought about re-connecting the existing wires on one pole and see what happens?  Then count the turns when they are removed and you will have an idea of how many it needs.

Stray thought. Will 2 'skewed' magnets fit? One high on the rotor, the other low.

G-