Q&A Practical build log generator Figuera

[Lasco]

I couldn't resist sending the community this link, even though it's not related to our subject.

https://www.youtube.com/watch?v=G6cycmBwLb8&t=31s

https://www.youtube.com/watch?v=ytCVQ-OZZmM

I will count wires and here is the file of measured DC voltage, current, and field

[kloakez]

I did a simple simulation, coil turns 1000, current 1 A, it gets up to 1.4 T. But I am not happy with it yet. The gap is 50 mm in this case.

       

If I try to put the variables in the equation to get coil turns and current for B_max = 1.5 T, I could do it like this (for DC):

N*I = 1.5*15*10^-2 / 1.2566*10^-6*15000 = 11.34 A

which should get to 1.5 T with one turn of wire. If I use 100 turns of wire, it should be 11.34/100 = 0.1134 A. Which does sound like it will not work since you already tried something similar. I'll try to figure something out.

[Lasco]

Hi thank you for your help
I will wind with 0.62 mm copper wire ( because I got it in my stock) and I will turn as many turns will fit without overflowing bobbin
Then I will test again 

I have made very simple tests with adding magnet to the one side of core and to my surprised resulted magnetism is actually addition 

Just as thought  perhaps Figuera used soft iron magnetised in correct direction to assist with magnetism

[kloakez]

I am really not sure about the results of the simulations so if it costs you time and money I'd advise to wait. In any case, I'd trust the computation from equations more.

0.62 mm wire has about 3 A current rating, I wonder how it will do.

[Lasco]

Don't worry
if we don't try we will never never know

Just saying

[kloakez]

Sure thing. That is how I went with my build too. I just didn't want to give you a bad advice.

I checked the gaussmeter measurements you made and if I put it into a plot and computed a slope (how much did the magnetic flux density increase by increments of current) and it shows slope of 1, that is as if there was just air core, no electrical steel core. I am really not sure what that means as I have never tried that practically, but I think that the core was already saturated and further increase of current was only thanks to the strong electric field of the coil. It is just an assumption. Will try that with my setup when I have time.

The modified excel file is attached.

[kloakez]

I checked the gaussmeter measurements you made and if I put it into a plot and computed a slope (how much did the magnetic flux density increase by increments of current) and it shows slope of 1, that is as if there was just air core, no electrical steel core. I am really not sure what that means as I have never tried that practically, but I think that the core was already saturated and further increase of current was only thanks to the strong electric field of the coil. It is just an assumption. Will try that with my setup when I have time.

So I was definitely wrong about the core being saturated. Today I made a similar test, measuring magnetic flux density in the center of the air gap and writing down the values from the teslameter. I have only 0.3 mm wire which should be good to 0.7 A and since I have two coils in parallel, I am assuming 1.4 A is fine, but I went to 3 A. The magnetic field was still increasing so the core was not saturated.
   

I also did another experiment, a simple circuit with a 12V switched power supply and a 12V fan. And I put the grid made of copper tape with a wire soldered on it and tried to connect it to one of the terminals of the fan hoping it would lower the input current. It did not. 0.1 T is definitely not enough.

Another way to make the magnetic flux density stronger is to make the air gap smaller. That could help mainly when the magnetic flux density is high close to the core and it is lower in the center between the cores.

Soo... hoping you get a really strong magnetic field from the new wiring!

[Lasco]

I would recommend to check this out
In this you find work that may be interesting to our subject 

https://www.gsjournal.net/Science-Journa...o,%20Gobbi

[kloakez]

I have been trying to bring this guy's publications to the attention of people building the Figuera generator but so far nobody paid attention. I think it contains a lot of info that if applied properly will lead to a successful Figuera generator. Wanted to build it first to be sure it really works.

[Lasco]

Hi guys

Very interesting development with my commutator build 
Finally got it working without spikes and disturbance 
It took extra pressure on the brush to maintain connectivity
Will post update shortly