Author Topic: Beginners frustration (Read 6513 times)

allthumbs · « **on:** June 26, 2007, 02:17:16 AM »

Beginners frustration

I had a ceiling fan on a 10' pipe turning in the wind just to work the bugs out before trying to make it generate but the nut that was securing it vibrated off and it came crashing down braking all but one blade.

I put a wanted ceiling fans for parts in Craig's List and the very next day I ended up with 9 ceiling fans for $10. I had planned on converting an induction motor as my firs try at making a generator but now that I had all these ceiling fans I thought why not try that first.

I had 10 neo magnets ½ x ½ x 1/4 and I thought 8 of them should line up with one of the fans that had 16 coils and if I used the rotor out of the larger one that fell that would almost give me 1/4 inch clearance for 1/4" magnets. I would only have to turn about .035" off the inside diameter which I did.

The fan that had the 16 coils was now .was now on the pole spinning in the wind and I had another smaller fan stator with 14 coils so I thought I would just try in in the rotor with the 8 neo's cemented in. 4 of the poles lined up with the magnets and 4 didn't. At 600 rpm in my lathe it put out 6.3VAC. I figgured that the magnets that didn't line up were canceling the others and that was why I was getting such low voltage.

I then took the other fan down from the pole with the 16 coil stator and put it into the rotor with the 8 magnets thought now I will get some real voltage out of it. I spun it on my lathe at 600 rpm and much to my disappointment it only put out 4.9VAC on the inner set of coils and 2VAC on the outer set of coils.

Where did I go wrong? Did I use the wrong number of magnets? Was the ..015" gap to small?

It did cog badly. I had thought of cementing the magnets at an angle but they were ½" x ½" and it didn't look too practical. If they had been 3/4" or 1" long I would have slanted them.

For pictures of these two different stators see my picture postings "two different stators"

AT.

Thumbs, here is that photo:

TW

stephent · « **Reply #1 on:** June 25, 2007, 08:30:22 PM »

Yeah, it can be frustrating to say the least...

But that's a single phase fan motor...if you have 16 coils--you need to match it with 16 mags--or the coils without any mags close will add resistance and they won't be adding any voltage....frustration.

But that thin a stator/coil combo will make skewing the normal way more then a bit hard.

Cogging is up to you to fix...but one coil---one mag will help bunches in output.

allthumbs · « **Reply #2 on:** June 25, 2007, 08:34:12 PM »

Would it help if I made it two phase?

RP · « **Reply #3 on:** June 25, 2007, 08:50:36 PM »

I think it's already two phase. The inner and outer coil sets are 90 degrees apart. For cogging, it may help to offset the magnets. In other words, set up eight magnets around the circumference the way you'd expect and then add eight more but shift these by the 1/2 the width of one pole shoe (either clockwise or counter clockwise).

In this way some of the cogging can be cancelled (with a modest reduction in output). Others here have done this on induction motor conversions.

allthumbs · « **Reply #4 on:** June 25, 2007, 09:31:38 PM »

The 8 magnets are cemented alternating + - + - and so on, if I add 8 more magnets between the existing 8 it then would be + - - + + - - + + and so on. This wouldn't work would it?

What if I were to take the outer coil and rewire it by cutting between each coil and extending it over to next coil. In other words coil 1 would go to 3, 5, 7, 9 etc. and coil 2 would go to 4, 6, 8 etc. I would then have two series phases right?

I assume that every other coil is wound in the oposite direction, now maybe that would cause a problem for what I suggested in the paragraph above?

I could also do this with the inner set of coils. Would that make 4 phase!!??

Has anyone had sucess removing neos that have been cemented in with J-B Weld without breaking them?

AT

tecker · « **Reply #5 on:** June 25, 2007, 09:36:52 PM »

Two mags per core fork at a slight angle I use 1/2 X 1/8 stacked ( cheapos ) . Hand spins 35 + both inner and outer phases . Get rid of the armeture core and add some 3/4 flatbar bend around let it settle into the end caps and shimm it into place cut to a 1/16 air gap and weld it ,or use some ceramic mags like WXY did

http://www.thebackshed.com/Windmill/FORUM1/forum_posts.asp?TID=305&PN=4

tecker · « **Reply #6 on:** June 25, 2007, 09:38:50 PM »

woops wrong pic That one coged big time

here's the one that's flying

tecker · « **Reply #7 on:** June 25, 2007, 09:40:39 PM »

allthumbs · « **Reply #8 on:** June 25, 2007, 10:15:42 PM »

hy do you say "Get rid of the armeture core and add some 3/4 flatbar"? Is the armature core causing a loss of power?

I didn't quite understand your picture below. It looks like you have two stacks of neos nest to each other, two in one stack and 3 in the other, explain?

tecker · « **Reply #9 on:** June 25, 2007, 11:20:37 PM »

Two stacks . One set of two for each stator section .

tecker · « **Reply #10 on:** June 25, 2007, 11:22:51 PM »

What's this is a space between mag sets

coldspot · « **Reply #11 on:** June 25, 2007, 11:35:26 PM »

Looking like fun so far!

"Was the ..015" gap to small?"

I think the only way to be

"to small".

Would be to have contact or touch.

tecker · « **Reply #12 on:** June 26, 2007, 06:48:03 AM »

With a the with a steel backing instead of the armature core you can use the larger stator .but that is an interesting Idea to mix and match the cores from larger fan motors .I've never stopped at Craig's list before very cool.

tecker · « **Reply #13 on:** June 26, 2007, 06:52:28 AM »

alternate north south of coarse

Ungrounded Lightning Rod · « **Reply #14 on:** June 26, 2007, 01:31:50 PM »

You should have 16 magnets arranged + - + - + -.

With only 8 you could do it + x + x + x or + - x x + - x x.

(With 8 in the + x + x configuration the return field would be in the empty spots (x) where the - magnets would be in the 16 magnet config, but with an expanded gap and lack of additional magnets reducing the strength.)

You're getting little output because half the magnets are canceling the voltage generated by the other half. The output voltage you see is just the imperfection of the cancellation, not the output the device would be producing if the magnets were correctly positioned.

Ungrounded Lightning Rod · « **Reply #15 on:** June 26, 2007, 01:34:01 PM »

I think it's already two phase. The inner and outer coil sets are 90 degrees apart.

That's correct, as is your cogging prescription.

allthumbs · « **Reply #16 on:** June 26, 2007, 04:15:27 PM »

I did not get an answer to the following questions. Maybe because it's a crazy idea.

What if I were to take the outer coil and rewire it by cutting between each coil and extending it over to next coil. In other words coil 1 would go to 3, 5, 7, 9 etc. and coil 2 would go to 4, 6, 8 etc. I would then have two series phases right?

I assume that every other coil is wound in the oposite direction or I would see a wire going over the top to the other coil, now maybe each coil being wound in the oposite direction would cause a problem for what I suggested in the paragraph above, right?

I could also do this with the inner set of coils. Would that make 4 phase!!??

Has anyone had sucess removing neos that have been cemented in with J-B Weld without breaking them? I realy need this question answered.

AT

allthumbs · « **Reply #17 on:** June 26, 2007, 04:21:34 PM »

Thank you ULR for for this idea, I may try that. Can the cemented neos be sucessfully removed without breaking them? I would have to remove every other one and turn it over and re-cement them.

AT

vawtman · « **Reply #18 on:** June 26, 2007, 04:58:36 PM »

Has far has removing the jb welded mags goes its easy i removed 16 with no problem.

Just use a small thin screwdriver.

I found jb isnt that good after that easy removal.

On another note ceramic mags that match the coil span would be best for this in my opinion.

tecker · « **Reply #19 on:** June 26, 2007, 06:09:34 PM »

They do alternate clockise counter clocwise .

tecker · « **Reply #20 on:** June 26, 2007, 11:56:54 PM »

I can get jb weld with a surface contact to let go with a hard tap to the steel.

News:

Author Topic: Beginners frustration (Read 6513 times)