magnet sizing for ceiling fan conversion

[divemaster1963]

howdy people.

My question is . I am converting a ceiling fan and am mounting the magnets. the magnets a have are two different sizes. 1st I have 12 1x1x1/2 mags. and I have 6 1x3x1/2 magnets. which will serve my pouposes better. I am new to this and am charging a bank of about 6 agm batteries. I already have a 90 watt solar charging unit system that has a regulator. can I add the wind turbin if I put directional diodes in the lines or am I asking for trouble and should make a new controller that can handle both.

thanks for all the help.

[electrondady1]

 google search the board

you become an expert and tell us.

i think the mags you describe are too big, and there are not enough of them.

lots of ceiling fan conversions in the archives.

good luck

[Warrior]

Hi, here's a post from the backshed from a member of this board:

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

Good Luck

[dnix71]

After reading your post and having the week off from work, I went shopping and tried a ceiling fan conversion. I used a $20 3 speed with light kit from Lowes and some neos borrowed from a shakelight. I scored and split one neo so it would be thin enough to fit.

After completely disassembling the fan, I drilled a small hole from the outside of the reluctor ring and then countersunk a larger one and set the neo disc in it.

I got 3 volts ac per magnet but no amps (enough to light a single LED from a Christmas light string). The winding wire is too thin. I stopped at 2 magnets because the outer ring deforms easily and the air gap isn't much thicker than a sheet of paper. It took a lot of work to make the fan spin without scraping after putting in the second magnet.

If you want to do a conversion that works, the ring has to be replaced, but that's tricky, because it's what holds the shell and windings in proper alignment. You might be able to just chop the 4 stubs that have the shell screws in them and put lots of magnets around the inside of the shell, or substitute threaded rod connectors. My fan has 16 split poles.

The winding would have to be redone, too, because they are much too thin to carry much current.

Even with just 2 magnets and no load there is visible cogging because the winding core is around laminated steel.

[ghurd]

"some neos borrowed from a shakelight"?

Sure they are neos?

G-

[divemaster1963]

what i was planning was using neo magnets from old hard drives I have  found a scap man that will let me have a truck load. all he wants is the platnum coated disc. i think i may be able to cut the holding ring using my dremal tool to the thickness of the mags. to fit them in without deforming the ring and keeping the gap consent. i have read where one person got 100 to 200 watts. I amy planning to combine the inner and outer coils to get more out. I am using this to add to my solar setup for powering my shop in the woods. I have to hide it from the tax accessors office. i have a bank of 12 agm communicatioon batteries and 2 very very big 12volt forklift batteries.  i need to appox. the proper sizing of the mags that i don't kill the output.

theanks for the info. this place is great.

[dnix71]

They're 3/8" in diameter and lift 5 pounds easily and are nickel plated. They have too much pull to be common ceramics. I tried neos from Radio Shack and those were much weaker. The RS neos are a cheap grade. The Curie point is 590F and the working temp is 176F.

These shakelights from the local 7-11 are bizarre. They are real shakelights, sort of. If you take out the 2 2032 Li button cells and fully discharge the 40mah 3.6v NiMH internal battery, you can shake it to recharge. But 3.6v won't light the LED much. The 6 volts of Lithium through a resister makes a really bright light. I replaced the NiMH stack with a polarized cap, but the current draw is so large that you get less than a second of light from that arrangement.

I bought some ceramic block magnets from HF (#97504) today. Unfortunately they are about 1/8" too thick to fit, unless I slice them thin. I'm going to try that later.