Roll your own Magneto (stator)

No biggie on the rewind, I have lotsa wire left. Question, Rohmell. How should I test the output of my magneto to compare it to the OEM's output? I mean, what type of testing unit needs to be used? I figure if anyone would be able to answer this it will be you or maybe someone else reading this. Any help is appreciated.
 
Awesome idea,

Simple yet effective. Of course I am very limited to my testing equipment, boiling down to a DVOM and a clamp on amp meter. I do think the clamp on reads small dc amps fairly well, so I may be able to compare that as well as the voltage output. I like the iron core with magnet wire wound on it, then hook up a 5 VDC power plug. A place to start, anyway. Thank you very much for the information.
 
Yes, exactly like you taught me on the test circuit ! And the wallwart is exactly what I was thinking.

Edit: or use the ac power supply I made for the CDI test rig. 6.3 VAC.
 
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Rewind photo. As of today I rewound the Magneto and made it through without a wire break. The silly counter failed on me, though. I feel I may have gotten too many turns on which is easiest to fix. I tested the ohms but don't trust my meter. I need to dig out my other unit. This meter read 525 ohms. And that spindle is fully wound ! Almost overfloweth. I just didn't want to stop. Also made my electro-magnet today for testing the magneto. Photos prly tomorrow.
 

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Okay, I used the other meter and got 527 ohms, so it was close. I hooked 6 VAC to the electromagnet and suspended it in the magneto. Output on the mag was 6.5 volts AC. Now all I have to do Is remove my OEM mag and test it for a comparison. Don't stay gone too long Impression, I like your input on this project.
 
Today I tested the OEM mag coil. Used the same magnet and power supply as yesterday. 6 VAC input, 10.2 VAC output. Now I need help figuring out what this means? I was assuming the higher voltage would be what I was trying to acheive? I did forget to mention the OEM mags' ohm reading. 330 Ohms. My rewound unit was 525 Ohm. Okay, maybe the higher ohms means lower volts out but may also mean more punch in the amps department? I think I need to go find ohms law and do some math.

Edit: Looks correct. My hand wound unit puts out about 2.5 times more umph than the OEM unit.
 
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Yes, you have the numbers correct. At this point I am dumb-struck as to what I did wrong. I will do a re-test within the next few days and will try to borrow a much better meter than my own. Thank you for your help.
 
Funny you should mention these dimensions. Here is a pic of everything in question. The electro-magnet is a steel cored barbell design that was easy to chisel out on the lathe. Common sense has taught me that magnets work best when in contact, so I decided to use an interference fit. The barbell is 1.311" long. Opening on OEM mag is 1.308" and rewound mag measures 1.303". Yes a tight fit on the rewind but certainly not over-done. If I were to take the fit down to same dimensions all around I felt that minor flexing could occure causing the magnet to oscillate or vibrate when energized.
 

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Well, removed the stud and all the weld, ground everything flat and smooth. I can see every single leaf and see that there is no contact. Randomly checking for continuity I find it everywhere, drat. Some places more than others. Get a wild idea and check out the OEM mag. Guess what? Random continuity in that one as well. And the OEM unit has not been touched at all. Makes me think a bit different about this magneto gig. Maybe I need to make the entire unit myself and do it the way it would be if it was made in the USA.
 
It won't be too hard, just need to make a cad drawing of the leaves and then send to a sheet metal fab shop that has a turret punch and does prototyping. It just may cost a bit, but I could probably get like 500 for the same price as is required to do one. Laminating them is easy if to have a hydraulic press. Choosing the insulating paper for between the leaves will take a little research. If money is no object, anything can be had. Sadly, money is always and object:)
 
Has anyone rolled their own magneto without the infamous "White Wire"? It seems to me that without the secondary winding, you could add additional turns to the spark coil, resulting in extra spark.

Any ideas on this?
 
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