My version of the Wood AX...the beginning

[steak2k1]

Well after reading and then some.... I decided to go ahead and try to emulate the Wood AX using some different materials and use some of the more up to date manufacturing methods gleaned from this site in my approach to the stator/rotor.

I was surprised how well the simple coil winder worked..that was kewl.

I have copied the resin filled stator idea (using a mold), as well as surrounding the mags with talcum powdered addition resin.  

I did have some air pockets within the stator and have now filled then with in resin.

12 mags are 1" X 3/8" rnd Neo's, coils are 40 winds of AWG 18. I have the stator wired in 3 coils for (I believe it is called), 3 pole.? using the Star connection.

The bridge rectifiers are 600V 40A.  Is that going to be enough I wonder.?  I believe so but would like to hear from others on this.

Lamination is next and although I tried to get silicon (not silicone BTW), steel..I am going to use instead some steel banding that is easily found and gotten (free).

It will be insulated, 1 long coiled piece as per Ed winstuffnow, and insulated with some sort of tape.  What seems to work the best..??

The Prop blades have been rough cut at 2' 6" ea long (all four of them - 1 is a spare as I am sure I am going to need it.!! LOL), and are made of laminated 1 X 6 Fir from good ole Home Despot. I used a Gorrilla type glue (Pro-Bond actually as Gorilla is just too darned expensive.!), and am clamping them for a 24 hour period.

Well I am now gonna have to wait for next weekend to continue...The house supervisor just won't let me go play during the week too much..but I think I will get one of the dbl handled carving blades I have seen in the Dans hands.

Thanx to all for their encouragment and tech help. And I do truly believe this to be one awesome board and am glad I have been able to partake.

rgds,

stk

[ghurd]

Is the ply wood still in the stator?

Anneal the steel banding in a fire.

G-

[steak2k1]

Hello Ghurd.

The stator is completely resin core and no plywood remains.  Basically I made a plywood mould just like on some of the pics in the Dans assembly of stories. The Stator thickness is 3/8" nominal.

What is the reason to fire the coil material..??  Won't that will only anneal it.?       I'm curious

I plan to roll my coil. Then will make a plywood mould for the coil such that when it is coiled & insulated, it will fit right in the middle of the coils in the stator.  I will then pour resin and some fiber cloth to stiffen it up and the whole unit will be one.

rgds,

stk

[ghurd]

Glad there's no plywood!

The annealing thing... Not real sure why, but it helps and everybody does it!

Maybe something in this will help.

http://www.fieldlines.com/story/2005/4/4/165529/9645

[kitno455]

uhm, maybe i missunderstand:

'it [steel lam coil] will fit right in the middle of the coils in the stator'

no. you want to put the lams BEHIND the coils, other side of the mags, so that the flux jumps off the mags, thru the lams, and back to another mag, passing thru two coils on the way.

allan

[ghurd]

Right.  Maybe have a look at this...

http://www.windstuffnow.com/main/alt_from_scratch.htm

G-

[steak2k1]

Yea a bit of a misunderstanding.  What I meant was that with the laminations on the backside of the coil, the laminate ring would basically sit on top of the open space made by the middle of the coils.  is that a bit clearer..(like mud they say.!! LOL)

Anyway, the laminates will be on the opposite side of the magnet rotor.

and thanx, I have seen the page by Ed.  good stuff.

One question though, in my first attempt to make a stator, I have some gaps (1/2"), between the outside edge of the coils. However so do the magnets and at the same spacing.  But this is not good now that I think about it (for the stator), as there is an open area that is not being used to produce power and to me there should be coil material beneath the magnets at all times..??

As well I think the stator is a bit too thick.  I think I will make another one and try for 1/4" in thickness, go with a few more windings (up to 50), and flatten out the coils such that the sides are actually touching...and use my glue gun to place them in the proper spot. (don't know why I didn't use it last time.?) As well I may make the top and bottom of the mould out of some extra Plexiglass 1/2" I have here...should make for a smoother top and bottom.  

I have lots of wire, resin is cheap and overall I am not really happy with the way my first attempt turned out. But live and learn and experience.  Like many, once attempted, next try will definitely be better...besides this is fun stuff..!!

thanx guys for responding and making me think more.

best rgds,

stk

[Ungrounded Lightning Rod]

Annealing (and tempering) changes the crystal structure of the steel.  Annealing makes it softer, tempering makes it harder.

That applies both to mechanical and magnetic "hardness", which are both related to the crystal structure.  (And the "harder" magnetically the material is, the more energy is lost flipping the field within it, so you want it "soft".)

However:

If you can put a second rotor behind your stator - even if it doesn't have magnets on it - it will do better than (non-rotating) laminations.

Also:

If you put laminations in the middles of the coils it will increase the generation considerably by reducing the effective gap, thus strengthening the field.  But you'll have to get the geometry right to avoid cogging.  (Fortunately, with a 3-phase set up you've already got significant cogging cancelation just from the relative spacing of the cores.)

Regardless:  Be sure you orient your laminations so the magnetic field enters and leaves by the edge, and "slides along" the edges rather than jumping from lamination to lamination in a stack, as the magnets move.

= = =

I noticed that you have significant gap betwen the winds of the coils.  If you do another stator you might make the coils' central hole bigger so the coils butt up against each other.  You gain more by increasing the voltage by having both coils generating simultaneously than you lose by the slightly increased resistance from the longer wire path.

[steak2k1]

QUOTE:

"Regardless:  Be sure you orient your laminations so the magnetic field enters and leaves by the edge, and "slides along" the edges rather than jumping from lamination to lamination in a stack, as the magnets move."  END QUOTE

ULR:  I am not sure what you mean buy orientation.?  As I mentioned, I have about 35 feet of this 1" steel banding.  I have coiled it up in one pce and this gives me about a 1-1.25" thick laminate.  I will likely do a very small tack weld to hold the whole thing together and off into the fire pit it goes later on this week.! Once annealed, I will untack..unroll, clean and insulate...will scotch tape do or should I use the campers best friend..duct tape (might be a bit too thick.?)

Does the insulation need to be on the inside of the material (in relation to the ring), or on the outside.?

As well does the end point on the outside of the ring need to be pointing in a certain direction.? with the rotation or against...or do either of these questions really matter..?  Seems I have seen some laminates made with small pces "jammed in place and as such neither of these questions come into play.

QUOTE:

I noticed that you have significant gap betwen the winds of the coils.  If you do another stator you might make the coils' central hole bigger so the coils butt up against each other.  You gain more by increasing the voltage by having both coils generating simultaneously than you lose by the slightly increased resistance from the longer wire path. END QUOTE

Ok..so rather going with more windings (turns), just make the coil (same turns - 40), itself a larger (ID), diameter.  This would of course have a greater amount of wire per turn than what I have now which would account for the increased resistance.  OK got that. And make sure that the edges touch or become "intimate" as far as edger contact is concerned.  OK Got that too.

Thanx muchly  ULR..I now have a little bit better insight into what the hey I'm doin!!

I will likely go with the stator I have now - check my results and then attempt to better the results with a new stator.  Gives me some experience and a feel for things.

I gotta say..been involved with a number of "hobbies"..this one promises to be the most fun and defintely the most rewarding of all.!

rgds,

stk