Igniters

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Brian Hutchings

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Does anyone know about igniters, as used by Henry Ford on his Quadricycle? I'm close to finishing a 1/4 scale model and have had some advice on the ignition but I'd like, if possible, to keep it as authentic as possible. I'm not looking for performance or even long running times, if it runs for 30 seconds or so at a time then I'll be well pleassed.
Brian
 
Brian,
Igniters are a common part of ignition systems used on the old hit & miss engines. I'm far from knowledgeable in them, but I know where you can find lots of information about them, www.smokstak.com
I know I have info saved away, but can't find at the moment. Attached is one article I did find (it probably came from smokstak.com).
 

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  • LowTensionIgnition.doc
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Brian

I have just (almost anyway) finished a Fairbanks Morse R80 which is a three cylinder engine and it is fitted with three igniters.

The principal as to how they work is simple however, making them so small is something else. Mine are oval in shape approx 12 x 8 mm. I have plenty of info and drawings etc if you are interested.

Send me an email to [email protected] and I will send you what I have.

Bruce
 
Last edited:
Brian,
Igniters are a common part of ignition systems used on the old hit & miss engines. I'm far from knowledgeable in them, but I know where you can find lots of information about them, www.smokstak.com
I know I have info saved away, but can't find at the moment. Attached is one article I did find (it probably came from smokstak.com).
WesPete,

I enjoyed the article on building a coil very much, and have been wanting to wind my own low tension coil for a couple years, but I’m slightly confused on one point in the instructions posted in the article. He mentions that after you reach the end of the first pass (and I assume every pass), that you wind back to the beginning and always wind the wire in the same direction. Does this mean to just lay the wire back to the starting point to start winding again, or should you reverse course and lay the second (and succeeding return courses) opposite to the direction run first.

Sorry if this seems obvious to most, but this is an excellent article and a good start for my first coil. I just have never taken one apart before to see how they’re wound.

Thanks in advance for any clarification you can provide.

John W
 
John W

You just wind back the other way. Providing the turns are all in the same direction, it really doesn't matter how you go about it. You are only using low voltage so the voltage difference between turns is minimal. If you were winding a high tension coil that would be a different matter. You are using DC so the current is limited by the resistance of the winding wire. For an igniter, you need a minimum of 1 amp preferably 2 amps at 12 volts in order to saturate the iron core. It is the collapsing flux that creates the high voltage ( eg around 200 volts ) spark when you open the igniter points.

Bruce W-S
 
John W

You just wind back the other way. Providing the turns are all in the same direction, it really doesn't matter how you go about it. You are only using low voltage so the voltage difference between turns is minimal. If you were winding a high tension coil that would be a different matter. You are using DC so the current is limited by the resistance of the winding wire. For an igniter, you need a minimum of 1 amp preferably 2 amps at 12 volts in order to saturate the iron core. It is the collapsing flux that creates the high voltage ( eg around 200 volts ) spark when you open the igniter points.

Bruce W-S
Thanks Bruce! While I’ve dabbled in making circuit boards and installing components, it’s always been to someone else’s plan so I’m no electrical engineer!

thanks again for the explanation,
John W
 
One thing nobody mentioned is that good igniters all seem have some way to snap the points open very quickly. If the points open slowly the spark in the gap is too tiny to light the mixture and will dissipate by the time the points get wide open.
 

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