Coils, Winder and Questions

[lingcodnine]

Good work mrcorrade. A 'core' (assuming metal of some kind) is NOT "needed" for any coil. It will increase inductance if that's what you're after. Making the overall size smaller too. BUT the core can introduce interference, particually in audio applications.

Would have liked to see it running.

[mcorrade]

@lingcodnine sorry my friend for not showing it run. I've since gone to a manual crank to wind coils. I found I have more control over the tightness and neatness of the coil that way.

[lingcodnine]

@mcorrade Something I didn't think of when I was doing alot of coils: Maybe the small spools of enameled copper wire might already to close to what I;m trying to produce?!? So i'd measure first. Of course I was only making audio crossovers. I had a Amprobe Meterman 37XR (Fluke handles them), it was great. Too big, I'd whack some wire off. Good Luck. J

[mcorrade]

@lingcodnine ya I used them as well. I eventually just started making my own. I would buy some thick plastic from a home store and use different hole drills and PVC tubing. I found it easier then chopping down old wire spools.

[Headshothorror4488]

for real, i understood everything he said but cant help cause im learning. Maybe u to are clueless kid ,2 comments below

[cessna151]

to use the words of Napolian Dynomite, " i dont understand a word you just said"

[mcorrade]

@cessna151 ya ok. So you needed to tell me that instead of just moving along?

[williamblake69]

pancake yes ...... core nooooo

[salzahrah]

so...

did u find the answers yet or what?

hahaha

[PhantomMigKiller]

What are you trying to make? I am not sure if you are trying to make a magneto, or if you are trying to make a position sensor. If you are trying to make a position sensor, you might consider using a Hall sensor or even an optical sensor. I learned a long time ago that coils are heat-sensitive when used as a sensor.

[PeroPlacebo]

i need help. I want to make a tatoo gun but i dont know what cind of coil i need to use. If anyone knows how long and wich diameter wire and core i need to use please tell me. THANKS...

[studentofscience]

You can use a lazer (lazer pen) and a IR collector to (aluminum reflective tape) trigger a mosfet. The tape can be as long as you can feel the push. It should give you better results

[8abbadon8]

a magnet that has a length 10 times greater than its diameter will produce nearly all of its (1/2 rated B) field at its surface.

if the length is less, the field ratio is reduced at the surface. cubes are a 1/3rd or less.

pancake coils captures flat b fields produced by flat magnets.

long coils better for longer, thinner magnets that projects its field further.

Back emf from coil acts like attracting magnet to the passing magnet. ferrites increases this action.

[8abbadon8]

the current is produced by the voltage(V) and resistance(R) and is governed by the energy(B) entering the coils.

Remember, the mag field produces an induced emf (V) in the coil.

V/R= I(current) and is only limited by the energy input. To increase I, you have to increase V or lower (R).

we increase the energy (B) by increasing the RPM because the number of magnetic (B) pulses will increase within the same time, hence the average induced V increases.

Using bigger wires reduces R.

[dwatq]

OK,probably the best place for you to start is search on "axial flux generator" for the flat style coil with the air core.

In regard to the different spools that you've made - the longer one will need a core, the flat one will not. There's alot to understand here, but I applaud your great work and engineering skills. Good Luck.

[mcorrade]

Thanks Your one of the first who's told me something that I can really use. I figured that the flat coils didn't need a core but wasn't sure about the longer coils and now I know.I realize that a coil with a core will produce more drag on the system so I want to avoid them. I also needed to know the correct thing to search for and "axial flux generator" is what I needed. I've been asking coil questions for a long time because I know it's one of the most important parts of any generator unit.

[Drevtoobe]

I suggest that you do some basic research. When a magnet flies by a coil, you can visualize the standard magnetic lines of flux that surround the magnet passing through the coil. If all of the loops of the coil are larger then the end face of the magnet, then you can assume that the coil "catches" or "sees" all of the magnetic flux from the magnet.

The coil reacts to the CHANGE in magnetic flux with respect to TIME.

[Drevtoobe]

A coil that's a single turn of wire picks up exactly the same amount of energy as a coil that's 1000 turns, assuming that they are both roughly the same size. The higher the number of turns, the higher voltage and less current for exactly the same energy pickup.

The wire gage means very little, but as the wire gets finer and finer, the resistance of the wire gets larger, and that represents lost energy.

[marthale7]

The best I have found is to test each different one. Test them under load. The best core I have found is the the parts you find on a computer monitor cord... which looks like a cylnder when you cut it out. That works teriffic for me. And like me you are running out of copper. Expensive stuff :)

[rudiblackrahmadi]

but if you like to use the low rpm generator where the coil's length is only 50 - 100mm, i guess the iron core will not give the juice as in bedini's, it also sticky area which surely will slowdown the speed.

lastly, i guess... giving some times to study the low RPM generator will give us some ideas.

looking forward for your next video. good luck with your good project.

[rudiblackrahmadi]

as for the shape of the coil they are using a rectangle shape. some people reports that this shape is better than rounded shape.

most of them are using single direction coil connected in 3 phase configuration.

as for me, i'm going use their approach but using around 200 turns.

the bedini's does not need huge amperage nor voltage to work. i just need to make sure that the generator will make some "juice" at a very low RPM.

the iron core surely nice on bedini's coil due to the bobin's length.

[rudiblackrahmadi]

to my (poor) knowledge, thick wire will give more amperage & more turns will give more voltage. for example if we are using 0.7mm wire at 400 turn at 500 rpm will give us 5vac. now if we put more turns and others remind the same then we got more VAC but less amperage.

looking on some low RPM generator, they are using very few turns (compared to bedini's) which only around 30-50 turns and using 1mm or bigger. with this set up, they are aiming at 12vac which is more than enugh to run any bedini.