Well back to work on the 6" genny.
I finnally bought myself a decent camera, now to learn to use it better. Most pictures turn out great, but some things under the CFL lights don't yet. I think there is a setting for that though, have to learn how to use it.
Today I turned the mold on the lathe for the stator. 4.5" center, 8" Dia outer.
This was the door off an old desk or something. I thought it would be sawdust and glue, but it was more like waferboard.
I sanded the inner area after turning it. To keep the resin from sticking I waxed it very well.
To wax it I used a large candle. I heated the mold with a heat gun and then the candle to melt it. I ran the melted wax all around the inside of the warm mold letting it soak in. Then I took a softend wax chunk and rubbed all around the inside and the edges.
The bolt in the center was how I mounted it in the lathe, but then it stuck out the backside. I drilled the center hole a little smaller than the carraige bolt and threaded in the bolt, I used a double nut to lock onto the threads and draw the head into the wood by screwing the bolt in tight, then I ran 1 nut and a washer up tight to the wood to lock everything tight.
Mold.jpg
Next time I will make a crank type winder like normal. I figured with such small coils I would just wind by hand, my fingers are still sore. I just pulled the wire around the 1/2" spool I made by hand and tight too! 70 turns per coil, 18 coils!
In the pictures the left side is part of my normal winder, that is the spool and handle for winding the coils for the 10'.
In the vice on the right the purple thing with bolt sticking out is the 1/2" spool for these coils, front and nut removed.
I wound that wire onto the left spool from a 4lb 7oz cloth and resin coated coil I got at the scrapyard, that full spool did not make a dent in the coil.
6inparts.jpg
Here are the 18 coils. When I was winding these and checking with the template they appeared to be comming out correct at 70 turns, untill I got to about 12, then I could see they were running on the large side. When done I had 17 coils and room for about 1/2 of number 18. The coils have a 1/2" center hole and the wire is 1/4" thick. This gave me a coild about 1" OD, I figured it out and I needed about 0.95 OD each to fit in 18. Well, remember that vice in the other picture? I placed the coils one at a time into the vice and crushed in the sides a little bit to make 0.95 roughly. But this also caused the coils to get a bit loose and sloppy. When laid in the mold 17 fit perfect! WHAT!!!
Ok, now it was go for a loose 16 coils and change everything or get creative.
While looking for some sewing thread to wrap and tie up the coils I found something FAR better!
Artificail Sinue. Left over from when I did leather working a bit I had a nice large spool. Now if you don't know what that is and with my bad spelling you may not, Artificial Senue is a very strong waxy type string basically and sticky too.
That was perfect! I tied the coils very tight on each leg to crunch them thinner and very tightly together leg to leg to crunch them in width. I made basically a straight string of coils then pulled them around in a circle.
Coiltied.jpg
Sinue is very strong but thin, and being sticky pulled tight and onto itself it holds well and knots are thin and hold well also. Being sticky it does not slip around on the coils like thread or plain string would.
After I had tied all 18 coils I place them in the mold, hey geuss what, THEY FIT!
Actually instead of being too large as before now they were a tiny bit short for the full circle. I tied the two ends together tightly and It's a perfect fit and tight on the center.
18coil.jpg
As you can see, I plan to bring all ends to the outside of the stator. I hope this works for me. 18 coils, 36 ends, going to be easy to make a mistake wiring them so I'll really have to watch that close.
I have tagged all of the end wires with a paper and bent over the end also to tell which is start or ends. I tried to place the 2 wires for a coil comming out above that coil and have them taped down with Scotch tape for now.
I was going to cast some resin just to hold everything in place for now and bond it all together tight. Not casting the full stator. I think I will make another mold to cast the full stator. I would like more room in the center for some resin, maybe 3.5" center instead of 4.5" to give it more strength, and perhaps a 9" dia to have more room for mounting points further out away from the coils. The stator should be just about 1/4" thick when done.
taped.jpg
Sparkey says, "Heck the other guys get PIZZA, all I got was a Brawt"
