Ignition Box

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awake

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Following the lead of Brian Rupnow and others, I decided to make an "ignition box" to hold a battery and automotive coil, with leads that can be hooked up run to an engine that has points and condensor ignition.

What I came up with is a 3d printed box and lid:
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One side of the box has three connectors, one each for ground, points, and spark. The other side of the box has two connectors, ground and 12v, and a SPDT switch with center off. When the switch is moved to the "CHG" position, the battery is connected directly to the GND and 12V connectors, allowing it to be charged with an external charger. When it is moved to the "RUN" position, it is wired up to run the engine. And in the middle, of course, nothing is connected, allowing a way to switch off the engine:

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Yes, as you can see, I need to do some tuning on my 3d printer to reduce the "ringing"! And I need to put some white paint in so that the letters are more visible / readable. But it works!

It is not obvious from these pictures, but the box is printed so that there are recesses in the box itself and in the lid that "capture" the battery and the coil and hold them in place. You can see a bit of that in the next post, where I have a picture of the box being printed.

Meanwhile, here it is, hooked up to my first engine, the "Steel Webster":

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Here is the underside of the wooden platform, showing the wiring running through channels, held in place rather sloppily with some hot glue:

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In case you are interested, here are a couple more odds and ends. First, a picture at around 20 hours into printing the box (out of about 22.5 total):

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And a video of the box being used to run the Steel Webster, just because I can't ignore any excuse to run it!



Finally, in case anyone is interested in printing out this design, I've attached links to the .STL files - they are too large to upload directly to the forum:

http://www.wakefieldphd.com/hobbies/ignition_box.stl
http://www.wakefieldphd.com/hobbies/ignition_box_lid.stl
 
Singles sound so uniform running at slow idle. I'll be taking mine off the self to run a couple tanks thru before it get too hot in the garage. Very nice awake!
 
Thank you for sharing the video. It has a nice sound. Mine sounds similar and has a lighter flywheel made from a weight lifting plate.

Cheers,

Andrew in Melbourne
 
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