Jerrys first dual rotor.

[Jerry]

Some thanks for insperation first. Thanks Dan B for the 12 magnet 9 coil examples I saw at Hugh Piggots work shop on Guems Isl. Thanks also Hugh for all your great work and shareing.

Hiker thanks for the saw blade rotor disc idea. From your work it was proved that it could be done.

This was my first completed disc alt. I had started 2 others but they kept getting put on the back burner. Well this one is not flying yet but it has been wind tested.

This is the Jerrys first poured stator story continued. Hope fully with pictures.

The board and puter gliches have held this story up for a while. I'm still haveing puter problems so I hope this story and pix will post.

I'll try a picture post here of the completed unit as test in my S-10 wind test truck.

If this works I'll continue the story in reply to this. I won't use post a coment. It allwas scrubs my coment.





                     JK TAS Jerry

[Jerry]

OK so far so good.

                        JK TAS Jerry

[Jerry]

The rotor started out with six 10" commercial saw blades. These have an 1.5" center hole. I get old saw blades from a blade sharpening shop freind. One is shown with teeth. But I machined all the teeth off. I'll not be using saw blades again. They are way too hard. Also I think 1 solid pice of mild steel will be better?





Then the blades after cutting.



                    JK TAS Jerry

[Jerry]

These saw blades are thick enough that 3 stacked up make one rotor a liitel over 1/4" thick.

I needed a hub to mount the rotor to. I used the magnet end cap from a 12" speaker. I machined this to fit the 1.5" hole in the saw blades. I also used the 3 holes in the saw blades as a guide and drilled 3 holes in the end caps. I drill a hole in the side of the hub and tapped it for a set screw to keep the hub taught to shaft. Pix shows shaft, hub, saw blades shaft coller and end bearing.



                         JK TAS Jerry

[Jerry]

I wanted to use some scrap materials I had around. We built some mall displays for a reatail customer last year. Parts of these displayes used fiberglass sheeting. The type used for making shower stalls. It comse in a 4'X8' 1/16" thick sheets at a cost of $30.

We had a bunch of 2'X 4' scrapes left over. Neet stuff. I used it to make templated for coil placement as well as magnet placement.





Next cut version for magnet placement.



                  JK TAS Jerry

[Jerry]

This alt is the 12 magnet per rotor with 9 magnets stator. Since this is my first atempt at a disc alt I didn't want to waist and good or expencive parts and I was not hopeing for or expected very much power. Its just a training project. I also wanted to try a couple ideas out. If they didn't work no big deal?

I know laminated stuff has good strength. This gave me an idea about the fiberglass sheet. We make speaker boxes at my car stereo store and have a nice router attachment for making nice round holes. The idea was to make a stack of enough fiberglass discs to be 1/2" thick. This took 6. Next a template was made and holes were cut with a hole saw for coil placement. After cutting the double holes out for each coil the center fell out. It will be but back in latter during coil installation and resin pouring.





Next the center that fell out.



               JK TAS Jerry

[Jerry]

To keep this unit cheap I'm using the LOwes 98 cent ceramics. These measure 1-7/8" X 7/8" X 3/8".

I'm relizing I'm not getting all the pix in the right order. However I think you'll see what I've built here?

These are the speaker end caps after machining.





Heres the coil template.



                     JK TAS Jerry

[Jerry]

Time to wind some coils. My coil winder is a qwicky. After winding 9 coils at 300 turns each I'm going to buld a much better winder befor the next alt and it will have a counter. I lost track of turns too manny times ( interuptions?). So I just wied the coils to see how close they were? The 300 turns was do to, I had the wire and to get as much voltage per coil posable with the wire I had.









Now checking coil fit on template.





                       JK TAS Jerry

[Jerry]

Next I checked to see how coils and magnets set next to each other.















                    JK TAS Jerry

[Jerry]

A couple notes. The blue carpeted boards on the winder put tension on the wire to keep it taught for a tight coil. It just opens up then closes to pinch the wire.

I used a scrole saw to cut the fiberglass sheet. Cut real easy. Now a sires of pix on the stator. The thin wire just goes between the layers of sheet. If it were thicker I'd just drill a hole for it to come through.I placed the coils then poured in the resin. This method only took 16 OZ of resin. With out the fiberglass shett it would take a bunch more. After the resin was poured in a top and bottom board was clamped over the stator. I wraped the boards in sandich wrape to eliminate sticking of the resin to the boards. The boards are MDF. These rounds were left over from our speaker box making.









                    JK TAS Jerry

[Jerry]

A few more pix of stator construction.



 



                      JK TAS Jerry

[Jerry]

Stator now in press. The big squizes. This made the resin squish out between the shetts. This made it a littel hard to cleal up after casting. Next time I'll glue the sheets together befor the resin goes in.







Stator out of press.



                        JK TAS Jerry

[Jerry]

OK stator is done, magnet rotors are done. I now need a way to hold it all together.

I'm using a shzft so I need a bearing on each end of the shaft. You may have noticed the old emty speaker baskit in an above picture?

Being in the audio biz for 40 years I've acumulated 100 or maybe much more than that speakers.

The speakers that gave up there magnet backing plate will now become the holder for this disc alt. I've also collected 100s of ac motors for motor conversion. It worked out to just mount motor bearing end plates were the magnet asemblys were.

The magnet discs are 8.75" diameter so I used cast aluminum 12" speaker baskets. It saw easy to router out the fiberglass discs. They turned out extreamly strong.





Cleaning up speaker basket in lathe.



More basket pix.











                        JK TAS Jerry

[Jerry]

Pix of complete unit ready for wind testing.







                  JK TAS Jerry

[Jerry]

OK heres the ready for test pix.







                         JK TAS Jerry

[Jerry]

I've learned a bunch from this project. I will now build another with these changes, NEOs not ceramics, larger gage wire fewer turns, 2 fullwave bridge diodes not 9, 3/4" shaft instead of 5/8", solid mild steel rotor discs. However it was fun. It takes much longer to build disc alts compaired to motor conversions.

I have some 15" speaker baskets and some NEOs and bigger wire so all I need is time. Next rotor will be 12".

I only expected 100 watts max. Here are the wind test numbers it did. All 9 of the diode bridge were wired perelell.

5 mph 1 amp 12 watts, 10 mph 2.5 amps 30 watts, 15 mph 5 amps 60 watts, 20 mph 10 amps 120 watts, 25 mph 12 amps 145 watts, 30 mph 246 watts and 35 mph 22.5 amps 281 watts.

These numbers trac almost the same as the 50v Ametek with the same blades. Blades were 49" tip to tip 3 blade Jerry blade plastic.

Want to try the Ed Windstuff type wave coil arangment next.

                          JK TAS Jerry

[pyrocasto]

Jerry that's pretty awesome. Nice job.

So, does that make 14?

[hiker]

looks cool jerry-not bad for  ceramics.what kind of volts was it putting out?

you plan on knocking off those ceramics and putting on neos for a test between the two?

[sh123469]

Looks like a great job, Jerry.

Lots of hard work and a very nice looking finished product.

Not to be nit-picky or anything, Jerry.  The pics are so large, it took 20 minutes for me to get the whole post on-screen.  If you resize your pics before upload, they won't take as long to upload, eat as much bandwidth from the server, take so long for us dial-up users to get to see them.

The size tags in the system just send the whole pic and then instruct your browser to scale it to a certain percentage of screen width.

It's great to have such large detailed pics of your work.  Just takes what seems like forever to download.

I have seen lots of posts on here about using aluminum in the structure.  Do you think you will have any stress related problems witht he aluminum?

Great job.  Hope we get to see the other one when you get it finished.

Steve

[Jerry]

Hi Hiker.

I'm going to leave this one as is. It will be easyer to just build a new one with the upgrades.

I will weatherize this one and fly it as is. It is a 12 volt. There are some voltage readings for it in my First poured stator post from a few days back.

I may use this one for 6 volt charging?

                           JK TAS Jerry

[Jerry]

Pyro and Steve.

There are 14 on the roof now. This will make 15. Steve sorry about that. I am a computer iliterate. So its a mirical I can even post a picture.

I've posted pix befor but not this many all at once. I'll try to shrink things down next time.

Again I'm sorry. I didn't want to cause inconvenience I just wanted to share my project. I guess I was a littel excited.

I only know enough computer stuff to be dangerus.

                          JK TAS Jerry

[hiker]

didnt take long at all here--56k modem-and its only running at48000bps..

of course mozilla firfox cuts it down to size in no time..

okay---no more punch lines for mozilla!!

[monte350c]

Hi Jerry,

Some things just look "right" and that idea you have for the two speaker basket frame is a real piece of ingenious work!

It will be interesting to see your output with the neo magnets. You know, these neos are coming down in price so much that it hardly seems worth it to do the ceramic thing anymore.

I just bought a bunch of those 2 x 1 x half inch ones from our host and was amazed by the price. It's a lot of magnet for the dough.

Great work on the stator too.

Ted.

[baggo]

Hi Jerry,

Great work as usual. That's a brilliant idea to use the speaker baskets for holding the bearings and the stator. I shall have to try that myself. Could save a lot of work. It also means the stator can be better supported all the way around the outside edge.

John

[Jerry]

Hi John

Thanks for the kind words. Yes this unit turn out very strong and the 360% support on the stator helps that stringth.

The 2 very large 1.5" shaft colers at the back side will make the yaw bearing. I'll mount the genny on EMT conduit. I use a shaft coler on the mast and let the genny just pivot on the mast. This is the same as pipe over pipe. I also use a shaft coler on top to keep the genny from lifting off the mast. I grease the pivot part up with bronze never size. Works great.

I'll post a (small if I can) picture when I get this one flying.

                        JK TAS Jerry

[picmacmillan]

hi jerry...good job, i really enjoyed reading the post....i have a couple speakers like yours....real good  idea..and you got some good power too...take care...pickster

[Jerry]

Thanks Pickster.

I started rounding up parts for the next disc alt. It will very simular. 8 NEOs per rotor.

It will be single phase. 8 coils. 8 rectifiers.

                        JK TAS Jerry

[hvirtane]

Hi,

this is a really nice machine.

Why not trying a big diameter

alt with ceramic magnets?

Hannu

[Jerry]

Hi Hannu.

I'll most likly be trying that and many other types and sizes. I'm working (when I find time) on a slightly larger NEO alt.

Had broblems with the first coil for that one. I tryed to glue the winding as I wound. I used grease to keep the coil from sticking to the coil form but it stuck anyway. Had to through that one away so back to the start. I would like the coils to hold there shape after they come out of the coil winder form?

                          JK TAS Jerry

[para t8]

jerry,looks nice and easy too.im doing the 12"rotor thing too,hoping to have it up,it was spring but i think its going to be summer,anyway thanks for the info and your time.good luck with your next project.happy new year.  para t8