Antique Engines and Old Iron
[Home] - [HELP] - [Forums] - [Library] - [Photo Gallery] - [Groups] - [Classified Ads] - [Subscribe] - [Links] - [Books] - [Sponsors] -

Go Back   SmokStak > SmokStak® Antique Engine Community > Magnetos, Ignition Coils and Spark Plugs
Forgot Password? Join Us!

Notices

Magnetos, Ignition Coils and Spark Plugs Discussion about magnetos, buzz coils, spark plugs, ignitors and low tension coils.

Magnetos, Ignition Coils and Spark Plugs

Single Coil Magneto Magnet Charger


this thread has 48 replies and has been viewed 2746 times

Reply
 
Thread Tools Display Modes
  #1  
Old 08-20-2018, 09:49:15 PM
Boris Boris is offline
Subscriber
 
Join Date: Oct 2006
Location: Ripon, Wisconsin, USA
Posts: 57
Thanks: 1
Thanked 93 Times in 23 Posts
Default Single Coil Magneto Magnet Charger

I have designed and built a single coil magneto magnet charger that is compact and powerful. It uses a single horizontal coil consisting of 160 turns of 12 gauge wire. It is powered by a 12v car battery and draws about 100 amps during the charge pulse. It weighs 15 lbs and is 8” tall. It is controlled by an ignition key switch witch activates a starter solenoid for the current pulse. The top armature pads can be adjusted from 5/16” to 4” gap, as well as set at angles.
The horizontal single coil design makes it compact, easier to build, and reduces the magnetic flux path length compared to the more common two vertical coil design. It has worked very well. I can post performance measurements and construction details if people are interested. Comments and suggestions much appreciated. Thanks, Robert
Attached Thumbnails
Click image for larger version

Name:	MC1.jpg
Views:	287
Size:	150.9 KB
ID:	316760   Click image for larger version

Name:	M6.jpg
Views:	267
Size:	140.6 KB
ID:	316761   Click image for larger version

Name:	MC4.jpg
Views:	262
Size:	145.5 KB
ID:	316762   Click image for larger version

Name:	MC5.jpg
Views:	260
Size:	153.7 KB
ID:	316763  

Reply With Quote
Sponsored Links
  #2  
Old 08-20-2018, 11:31:44 PM
Joseph Cissell Joseph Cissell is offline
Subscriber
 
Join Date: Jan 2007
Location: Fancy Farm, Kentucky, USA
Posts: 238
Thanks: 4
Thanked 94 Times in 81 Posts
Default Re: Single Coil Magneto Magnet Charger

Robert, I would like to see the measurements and the construction details so I can build me one of these chargers. Thank you and have a nice day. Joe A.
Reply With Quote
  #3  
Old 08-21-2018, 06:30:19 AM
BV071747 BV071747 is offline
Subscriber
 
Join Date: Nov 2012
Location: Tekonsha, Michigan
Posts: 124
Thanks: 99
Thanked 37 Times in 22 Posts
Default Re: Single Coil Magneto Magnet Charger

I also would like the details so I can build one.

Thanks
Bruce VB
Reply With Quote
  #4  
Old 08-21-2018, 08:39:50 AM
Peter Holmander Peter Holmander is offline
Subscriber
 
Join Date: Nov 2004
Location: West Greenwich, Rhode Island
Posts: 441
Thanks: 795
Thanked 356 Times in 162 Posts
Default Re: Single Coil Magneto Magnet Charger

Cool design Robert. Did you use magnet wire for the coil? I too would be very interested in the details of how you made it. I've always wanted to make one, but the cost of magnet wire for 2 coils was out of my reach. And when you do see a used charger for sale, they are very expensive. Thanks for sharing !!
Reply With Quote
  #5  
Old 08-21-2018, 09:11:14 AM
JoeCB JoeCB is offline
Subscriber
 
Join Date: Feb 2008
Location: Farmington Hills, Michigan
Posts: 559
Thanks: 98
Thanked 339 Times in 175 Posts
Default Re: Single Coil Magneto Magnet Charger

Thank you Boris, very nice … I like it ! Looks like you used regular insulated 12 ga wire, like the THHN that has a thinner plastic insulation, yes? If so, do you think that this wire impedes the magnetic field build ? The THHN sure is easier to come by than the enameled wire... I have a big coil and had been considering using it for a charger.

Joe B
Reply With Quote
  #6  
Old 08-21-2018, 09:48:27 AM
Ronald E. McClellan Ronald E. McClellan is offline
Subscriber
 
Join Date: Aug 2005
Location: West Chester, Pensylvania, USA
Posts: 1,476
Thanks: 1,621
Thanked 1,078 Times in 507 Posts
Default Re: Single Coil Magneto Magnet Charger

Boris Congrats it is very well done. My American Bosch magnet charger is built the same way. Ron
Attached Thumbnails
Click image for larger version

Name:	DSC02880.jpg
Views:	215
Size:	162.2 KB
ID:	316815  
Reply With Quote
The Following 2 Users Say Thank You to Ronald E. McClellan For This Post:
  #7  
Old 08-21-2018, 11:57:55 AM
Jake Jacobs Jake Jacobs is offline
Registered-II
 
Join Date: Jul 2006
Location: Spring valley, Illinois
Posts: 379
Thanks: 1
Thanked 338 Times in 161 Posts
Default Re: Single Coil Magneto Magnet Charger

Quote:
Originally Posted by Boris View Post
I have designed and built a single coil magneto magnet charger that is compact and powerful. It uses a single horizontal coil consisting of 160 turns of 12 gauge wire. It is powered by a 12v car battery and draws about 100 amps during the charge pulse. It weighs 15 lbs and is 8” tall. It is controlled by an ignition key switch witch activates a starter solenoid for the current pulse. The top armature pads can be adjusted from 5/16” to 4” gap, as well as set at angles.
The horizontal single coil design makes it compact, easier to build, and reduces the magnetic flux path length compared to the more common two vertical coil design. It has worked very well. I can post performance measurements and construction details if people are interested. Comments and suggestions much appreciated. Thanks, Robert
construction details please. thanks
Reply With Quote
  #8  
Old 08-21-2018, 02:58:02 PM
Boris Boris is offline
Subscriber
 
Join Date: Oct 2006
Location: Ripon, Wisconsin, USA
Posts: 57
Thanks: 1
Thanked 93 Times in 23 Posts
Default Re: Single Coil Magneto Magnet Charger

The coil core used in this charger is a 1” x 4” mild steel rod. The side and top armature pieces are 1 1/4 x 2 1/4 x 3” iron blocks. The 2 flux conductor blocks are also the same size. I ordered the 6 blocks precut from a local metal supply company. I flew cut the mating surfaces of the blocks with my mini-mill for a close fit but the blocks from the supplier came cut quite square. A good filling to smooth them out would be sufficient. Everything is bolted together using 10-32 flat head screws. This minimizes the removal of metal in the flux path. The armature assy is screwed to a 1/4” aluminum plate 6” x 8”. An aluminum 3 x 5 x 7” box encloses the circuit below. I plan to add a wood base.

The core is wound with about 60 ft of 12 gauge solid THHN building wire. A 100 ft spool can be purchased at your local hardware store for around $25; no need to use expensive hard to find magnet wire. I used my mini-lathe to hold the assembly while I hand wound it; took me about a 1/2 hr. A second person could be used instead of a lathe. The wire was stripped bare for the first 2-3 turns of the coil to provide the ground connection for the beginning of the winding. No insulation was needed around the core rod or sides; the wire insulation is rated at 600V. 5 layers were wound.

The circuit is built with a generic remote mount starter solenoid and garden tractor 3 position ignition key switch. A 4 guage jumper cable set provides the power connection to a standard car battery which almost everyone has (just pop the hood and connect it). The ground connection of the cable is bolted to the al plate underneath. The + cable is connected to one side of the solenoid; the other side of the solenoid is connected to the end of the coil winding wire from the top layer. The ignition switch is hooked up to the solenoid in the standard way. 2 LED lights were used for indicators. No diodes are used to suppress induced reverse currents and so far haven’t had any trouble with that.

Before use you need to determine the polarity of the top armature pads. Use a compass about 6” away and pulse the unit to see what the polarity is and mark it. Adjust the top pads to accommodate your magneto and arrange the flux blocks if needed. Search the web to see how your magneto is charged. Activate the charger with the key switch for no more then 1 second per pulse. I use three pulses. The coil will get warm but not hot. Never hold the key on for more then a few seconds. Its frequently stated that a keeper must be installed after charging a bare magnet. I have found that it is not necessary. You can’t do that anyway when you charge up a complete magneto.

Hope this helps. So far I’ve pulsed it over 100 time with good results and no problems. I have done some performance tests that I will post later.
Attached Thumbnails
Click image for larger version

Name:	MC rear.jpg
Views:	180
Size:	167.5 KB
ID:	316837   Click image for larger version

Name:	MC inside.jpg
Views:	205
Size:	187.2 KB
ID:	316838   Click image for larger version

Name:	MC winding.jpg
Views:	185
Size:	143.2 KB
ID:	316839  
Reply With Quote
The Following 7 Users Say Thank You to Boris For This Post:
  #9  
Old 08-24-2018, 12:41:37 AM
cobbadog cobbadog is offline
Registered-III
 
Join Date: Aug 2009
Location: Coopernook. N.S.W. Australia
Posts: 1,381
Thanks: 2,682
Thanked 579 Times in 405 Posts
Default Re: Single Coil Magneto Magnet Charger

G'Day Boris, thank you for sharing this great design for a magneto charger. I now have to ask some silly questions, sorry!
1 - Is 'Iron' the same as "mild steel' ?
Just so when I go to the metal supplier I look as silly as I am.
2 - You mentioned that you stripped the insulation off the wire for the first 3 layers, but you pic of it in the lathe does not show that just insulated wire. Is the bare wire under a cover?
3 - I can almost figure out in my head your wiring but I'm not sure where the second end of the coil wire is connected. Do you have a schematic diagram please that also identifies the positions on the solenoid?

Sorry to annoy you with these questions but this looks like a project I need to do.
Cheers Cobba. (John).
Reply With Quote
  #10  
Old 08-24-2018, 06:49:30 PM
Boris Boris is offline
Subscriber
 
Join Date: Oct 2006
Location: Ripon, Wisconsin, USA
Posts: 57
Thanks: 1
Thanked 93 Times in 23 Posts
Default Re: Single Coil Magneto Magnet Charger

I love silly questions!
My metal supplier had 1 1/4 " cast iron bar stock which is what I used. I have since found out that wrought iron is better for magnetic applications, and mild steel is better yet (and easier to work with). So try to find mild, low carbon steel for the armature structure around 1" thick. Thick armature structure conducts the magnetic flux better.

Look at the left hand side of the core rod in the lathe pic. You will see at least one bare winding. I drilled a small hole 1/4" deep on the inside of the armature just above the core rod. I then stuck the bare end of the wire into it, bent it over, and started the winding. The back side pic of the charger shows on the right the other end of the 12 guage wire passing through the side armature and passing down through the aluminum base plate which is then connected to the solenoid.

The starter solenoid you get should have two large high current connections and two smaller connections to activate the internal solenoid switch. If you look at the wiring pic on the left side you will see the red wire from the coil connected to the top large bolt on the solenoid. The bottom large bolt is connected to the red + of the battery jumper cable.
I will try to draw up a schematic of the charger and post it.
Reply With Quote
The Following 2 Users Say Thank You to Boris For This Post:
Reply

Bookmarks


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

F o r u m Jump

Similar Threads Chosen at Random
Thread Thread Starter F o r u m Replies Last Post
Maytag flywheel magneto magnet charger pole blocks Lloyd H Magnetos, Ignition Coils and Spark Plugs 1 07-21-2015 01:31:59 PM
Magneto Magnet Charger Jimmy049 Magnetos, Ignition Coils and Spark Plugs 1 01-22-2015 11:01:54 PM
Is this a magneto magnet Charger Kris Eckhoff Antique Gas Engine Discussion 3 08-30-2013 08:35:27 PM
American Bosch Magneto (Magnet) Charger with Table Jim Martin Antique Gas Engine Discussion 2 03-03-2013 12:08:44 AM
Magneto Magnet Charger Tom Antique Engine Archives 7 08-26-2004 10:53:07 PM


Use "Ctrl" mouse wheel to change screen size.
All times are GMT -4. The time now is 06:30:12 AM.

Smokstak and Enginads site search!


All use is subject to our TERMS OF SERVICE
SMOKSTAK® is a Registered Trade Mark - A Community of Antique Engine Enthusiasts
Copyright © 2000 - 2016 by Harry Matthews P.O. Box 5612 - Sarasota, FL 34277