• If you like antique engines, vintage tractors or old iron machinery, register and join us. When you register on Smokstak, please give complete answers and fill in all blanks. IF YOU ARE ON WIRELESS OR SATELLITE, GIVE YOUR CITY AND STATE! NO ZIPCODES! All registrations are manually approved.

Magneto Charger


Hi does any one have plans for a simple 12v magneto magnet charger as doing things myself is always more rewarding than just sending parts away to someone else? cheers Robbie

Ronald E. McClellan

Last Subscription Date
Thanks John , those are the best plans that I've seen. The coils are 10" lg. and 5" dia. It uses a total of 30 lbs of wire (.0453" dia) 161.29 feet per pound =4838.7 feet. The other chargers that I've seen skimp on the iron and copper for an inferior unit. The same goes for the low tension coils. The original coils had a lot of iron and copper. They put it in for a reason! Ron


I made a charger many years ago for some Wico EK magnets. Lots of data on the web but basically you need 20,000 or so amp turns and a steel core large enough so as to not saturate. Folks want you to believe you need a charger with 30 lbs of wire and a weight of 100 lbs. No so.

For old style magnets such as the old Wico magnets then shoot for 20,000 amp turns with at least 2 inch diameter cores. How you get there is up to you. I used 2 inch cores although 3 inch cores may have been better. To get the 20,000 amp turns I used 600 feet of 18 gauge magnet wire wound in 6 coils all connected in parallel. Allowing for a slight voltage drop, I still should get approximately 21,000 amp turns from a 12 volt car battery.
The advantage of larger wire is less heat. The old style chargers could run all day charging magnetos. Mine will do 20 or so in a row before needing to stop and cool. If you are wanting to charge magneto magnets all day the go with a bigger style. Otherwise, smaller wire will work just the same. It is the amp turns not the diameter of the wire that is important.

Another option is to spend $20 on two supermagnets, counter sunk holes, and use those. You do not need an electromagnet to charge another magnet, an n50 magnet will certainly charge the old style iron magnets