Jim Mac's Figuera Thread

[kloakez]

First thing that comes into my mind is a rheostat. But the ones I have seen would not like 3000 turns per minute.

What about digital variable resistors? https://eepower.com/resistor-guide/resis...ntiometer/ 1024 steps sounds like pretty smooth sine, maybe even smoother many AC/DC converters. And you can control it through arduino. Considerable downside is they work at 5V.

Yeah I have looked for hours for already built options, but none fit the bill that I have found. And that 5V ain't gonna cut it.

Classic, a fellow who was banned on this forum replied to me on a different forum about an idea. Quoting:

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I have seen your post on mooker regarding a rheostat but i have been banned on that forum and I can't make any contact or post messages.

You can use a varistor and relay to substitute a rheostat if dynamic adjustment/control is desired, check my posts where I have put a link with chatgpt and see the arrangement i proposed to substitute a rheostat in Daniel Cook permanent battery topic.

This you let you use a cheap solution up to 240v 10 a.

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I think by Daniel Cook topic he means this thread, but I am not sure which of the ChatGPT conversations. Might be worth taking a look.

[Jim Mac]

I am back from international travels, so back to work!

I am going to try to make a commutator with LOTS and LOTS of contacts.  As I see it, Figuera's original design should work just like a dynamo that uses resistance instead of distance to pull away.  And perhaps everyone fails because the resistance jumps are too much, as it needs a smoother pull-away wave.

And as I see it, most people are expecting the input to lower or remain the same as we increase speed, but I am now expecting the current to increase as we make more output.

So my objective is to use lots of contacts to a resistor with very small ohmage between each contact.

[Jim Mac]

The plan is to build this commutator using a 4" PVC adapter and having the contacts on the inside so centrifugal force helps maintain the brush contacts.

I got it spaced so I get 90 contacts, which will be made with 10 AWG wire. 

   

[Jim Mac]

A lot more to do, but coming out good so far..

   

Spokes are in place and glue is Drying.  Motor / Base stands are printing.   I will probably first use sandpaper instead of a carbon brush to condition the metal contacts smooth then away we go.

[Jim Mac]

   

   

brush holders printing

[unimmortal]

Loving you work Jim Guests cannot see images in the messages. Please register at the forum by clicking here to see images. Guests cannot see images in the messages. Please register at the forum by clicking here to see images. Guests cannot see images in the messages. Please register at the forum by clicking here to see images.

[Jim Mac]

Loving you work Jim Guests cannot see images in the messages. Please register at the forum by clicking here to see images. Guests cannot see images in the messages. Please register at the forum by clicking here to see images. Guests cannot see images in the messages. Please register at the forum by clicking here to see images.

Thanks.  Having a little trouble with the brush setup ATM. That center ring didn't leave me enough room to get the brush assembly in the right position.

Re-doing that part so I have more room. Then I gotta get a brush setup made to put power on to the center shaft. So a little more to do still.

[Shylo]

How big is are the brushes going to be?
Are they always going to be in contact with two spokes at a time?
Or completely break free so only in contact with one spoke at a time?
You can fill the gaps between spokes with epoxy then sand smooth making sure all the spokes are clean.
Assuming your brushes are spring loaded.

[Jim Mac]

How big is are the brushes going to be?
Are they always going to be in contact with two spokes at a time?
Or completely break free so only in contact with one spoke at a time?
You can fill the gaps between spokes with epoxy then sand smooth making sure all the spokes are clean.
Assuming your brushes are spring loaded.

Morning!

The brush is much larger than several contacts, so multiple contacts at once. I got the contacts placed so close that I am hoping there is no need to fill in between. And yes- spring loaded but centrifugal force will also be assisting in making contact.

I also have some bronze wool arriving tomorrow, so if the carbon brush is too "clunky" I can experiment with that.  I don't care too much about longevity at this point, I can redesign later.  For now the objective is to get lots of contacts without breaking the connection for experimenting

[Jim Mac]

After many prints, still having problems.  The brush contact is "jumpy" and is not maintaining constant connection.  I tried a carbon brush and a bent copper wire, same result. The whole thing spins excellent and true. 

My Bronze Wool is being delivered today. I will probably weave it into a rope and fasten it over the brush.  I'm sure it will work, just a question of how quickly it will deteriorate.

Edit-  I just started running sandpaper on the brush to smooth and flatten the bars and it looks like it's working.  The contacts are getting flat.  We will see!