diy solar

diy solar

Building the sickest ® VAWT ever. Brilliant minds unite please!!

wholybee said:
Some interesting ideas, but not how it works. Torque is a rotational force. It doesn't directly compared to the force holding 2 magnets together.

Also, its the interaction between the magnets and the coil. The number of turns and size of the wire are critical.
Click to expand...

I'm an engineer, not a scientist. If I approximate pi as 3 or 4, I get a close enough estimate.
I'm saying that the force magnet applies to the turns of wire aren't going to be any greater than the force two magnets apply to each other, spaced as far apart as the magnets will be in his structure. (give or take a factor much less than one order of magnitude.)

I propose this lab test to demonstrate that magnetic pole pieces inside the windings and outside the magnets will be required to get high enough field strength to have a prayer of reaching 600W or 6000W at low RPM.

wholybee said:
Foot pounds is a rotational force. You can't estimate it as you describe.
Click to expand...

I can estimate the force on one coil that way. Multiply by the number of magnets or coils for total radial force.
Multiply by radius, which is about equal to (the King's) foot.
I've been doing this stuff since my childhood, calculating sprocket sizes, motorized bicycle speeds, etc.

wholybee said:
700 ft lbs is more torque than the 400hp engine in my car produces. It is an immense amount of torque.

70 ft lbs will exceed the structural strength of the frame using the construction being applied.
.
Click to expand...

70 ft lbs? That's 70 lbs at 1 foot, not much difference from what I would apply to bicycle pedals.
If his radius is 1' and there is 70 lbs of radial force, that's 70 lbs on the shaft and bearings. Easy enough to handle with water pipe, OSB, or whatever.

Yes, 700 ft lbs is getting to be a lot. More like water wheel for a mill.
Higher RPM is a better way to achieve 6000W.
 
brandnewb said:
I am so pissed off by the way this happy thread turned dark just now.
Why people why?
Click to expand...

Try some of these.
They'll make you feel better, AND cure you of Covid!


iu
 
sunshine_eggo said:
Because I've encountered dozens and dozens of people convinced they have the best idea in the world, and due to at least a fundamental lack of understanding of ONE aspect, their idea can be demonstrated to be completely wrong.
Click to expand...

He's not like the guy who was hoping someone could build for him a self-powered generator from hardware store parts. Just a bit off on the multiple of force x distance / time that is power.

And he's got spirit - "Let's Go, brandnewb!"
 
OK I took some of that prozac, like 20 of them in a 4 minute time span and can report I am all cooled off again ;)

In regards of the magnets I have, it seems they are listed as having a 12KG strength over the flat (long) side

www.magneetgigant.nl

60x10x5 mm vernikkeld N45

Voor al uw magneten en toebehoren; Magneten voor thuis, op kantoor, hobby en educatie. Magneetfolie, magneetband, zelfklevende magneten, rubberen magneten, speciale lijm voor magneten, magneetverf en meer!
www.magneetgigant.nl www.magneetgigant.nl

So, I will continue winding some test coils first as I finally got a clean cut hardboard coil template at 3.2mm thickness.

1638968882868.png
 
Hedges said:
Hold a pair of magnets spaced apart as far as the air (or copper, or plastic or OSB) gap they will see in this alternator.
Measure the force between them.
Click to expand...
I am failing misserably thinking of a way to do just that. Reason being is that if I hold my scale too close it will get messed up by the magnetic fields.
 
no, i think I have an idea. how about I putt 2 sets of those magnets on a piece of wood so far appart that the magnetic field cant mess up the scale readings and then measure the attractive streangth. we then need to divide my some measure . I am thinking divide by 2
 
winding 1mm coil wire is hard!. even though it's not stiff at all!!!.

I think the only way to do this properly is to wind at full scale ;( meaning the full 360 degrees
 
brandnewb said:
ugg, this will mean another 2 or 3 days added to this project ;( @Hedges is it at all okay if we use this 12kg value of magnetic puling force for the time being?
Click to expand...

12kg would be in contact. At any greater distance, force drops much lower. The 12kg rating is much higher than what it will experience passing over a coil of wire that has no magnetic material for a core.

brandnewb said:
I am failing misserably thinking of a way to do just that. Reason being is that if I hold my scale too close it will get messed up by the magnetic fields.
Click to expand...
brandnewb said:
no, i think I have an idea. how about I putt 2 sets of those magnets on a piece of wood so far appart that the magnetic field cant mess up the scale readings and then measure the attractive streangth. we then need to divide my some measure . I am thinking divide by 2
Click to expand...

Something like that. Put a block of wood and one magnet on top of the scale. Bring second magnet close to same pole so it pushes away, measure force vs. distance.

Or, put a piece of steel > 12kg on scale. Lower magnet towards it, reducing weight on scale. To avoid pinching fingers, wrap a piece of cloth around magnet and hang that over the steel.

iu


Some of us would use a spring fish scale.


Whatever force the magnet experiences can be used to calculate torque needed to rotate armature. That and RPM will represent maximum power.
Purpose of my suggestion is so you will feel how low the force is, but with a magnetic core (to go through the wire), higher force is possible because gap reduced.
 
Hedges said:
Or, put a piece of steel > 12kg on scale. Lower magnet towards it, reducing weight on scale. To avoid pinching fingers, wrap a piece of cloth around magnet and hang that over the steel.
Click to expand...
That is easily done. I have huge pieces of steel around here somewhere in my garage easily heavier than 12kg
 
To confirm this has anything to do with anything, you could also wind a single coil of wire (representing 1/96 of stator), run DC current through it, and move a 2-magnet mockup of your armature past it. Measure the force on coil. Then try iron core in coil and iron pole piece joining backs of the magnets. (or maybe 4 magnet mockup, pole pieces for each pair to be more like two rotors.)

Power needs speed, distance over time. But use this mockup to measure stall torque (force) by applying DC current.
 
Hedges said:
To confirm this has anything to do with anything, you could also wind a single coil of wire (representing 1/96 of stator), run DC current through it, and move a 2-magnet mockup of your armature past it. Measure the force on coil. Then try iron core in coil and iron pole piece joining backs of the magnets. (or maybe 4 magnet mockup, pole pieces for each pair to be more like two rotors.)

Power needs speed, distance over time. But use this mockup to measure stall torque (force) by applying DC current.
Click to expand...
yes sir, as soon as I am done with the following
 
1638979649978.png
at +-25mm distance the opposing force was +- 241g(gram)
at +-15mm distance the opposing force was > 550g

I'll admit that this test was mostly entirely manual and thus giving my trademark earthshaker hands not reliable at all.

Any closer and I would repel the whole setup over,.
 
Last edited:
brandnewb said:
View attachment 75014
at +-25mm distance the opposing force was +- 241g(gram)
at +-15mm distance the opposing force was > 550g

I'll admit that this test was mostly manual and thus giving my trademark earthshaker hands not reliable at all.

Any closer and I would repell the whole setup over,.
Click to expand...
I am willing to dig deeper constructing some kind of setup to make for precise and consistent measurements possible
 
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