Muller Dynamo

[Pirate88179]

Ron:

That is beautiful!!  Very well constructed, I wish you the best.

Bill

[e2matrix]

Well with the type of pressures a skateboard endures, I would sat that these bearings could be champions here.

Boca Bearing has ceramics. Last I looked was back in the time of the Whipmag. They have a lube called dry lube for them.

I had not gotten any for the project, but was interested at the time.

I used bearings from a hobby shop. I thoroughly cleaned out the grease and worked in graphite powder.  I had gotten rundown times of over 14 min from 1000rpms.  I have vids on YT, 2 in a row as there was the 10 min time limit.  It ended up much better than dry or any oils I had tried.

http://www.youtube.com/watch?v=FiGjK3P7JBY

http://www.youtube.com/watch?v=eVXtRSxm73g

Mags

That's impressive Mags!  What specific bearing is that?

[neptune]

I personally feel that hall effect switching is not the best way to fire the drive coils on this motor . For one thing , there are bound to be loads of stray magnetic fields in this device . This is a field of which I know very little . I think the answer is an opto coupler or opto isolator whatever the correct name is . So basically it is an LED and a photo transistor or similar . All we need is a cardboard disk  with holes in it mounted on the same shaft as the rotor  . Ok it will need a small battery initially to drive the switching . The big advantage is total control of pulse width and timing , and can be reprogrammed simply by making a new disk . Can anyone suggest a SIMPLE circuit for this , preferably using the same TIP42c transistor as before .

[i_ron]

Ron:

That is beautiful!!  Very well constructed, I wish you the best.

Bill

Thanks Bill, of course I should add that it is just for the mantle piece as an ornament...LOL, as a kid we used to have one of those clocks with the dodad that would spin up one way then reverse and spin up the other way, fascinating. But here with that thick base plate i can carve out many many pockets for batteries....I checked first and it will hide lap top bats like a charm.

Ron

[e2matrix]

i_ron, that's an impressive build.  Have you given it a run yet?  I'm sure you are aware of this but I've got to ask as it looks like you are on an aluminum or steel base plate and from the size of your magnets I'm wondering if there isn't some drag from Lenz effect happening?