Ignition system

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Jerr46

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Any suggestions on what is the best spark ignition for the hoglet engine and where to purchase?
 
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bluejets

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Make your own......cost maybe $40 with off the shelf bits on ebay etc.

Bits include 12V dc black box.... Gy6 cdi coil....hall effect and a couple of minor mod components.

If need a twin system, use 2 or DOC has a simple multispark diy system using a Ford coil on his Hoglet.
 

danallen

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As recently as a few months ago Roy at CNC was still selling his waste fire CDI ignition system. I bought one for my Hoglet.
 

peterl95124

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the Sage Geddy design is by far the best, you can either build it yourself (I have made several) or buy it ready made. It uses IGBT transistors which are designed for high current and fast switching, and the circuit has built in timeout so it doesn't matter if the engine stops with the points closed, and it can be used with either traditional points, micro switches, reed switches, hall effect sensors, optical sensors, or what ever.

CDI is a much more complicated design which isn't necessary unless you're running a multi-cylinder engine at very high speed, a problem I've never had, even my V12 Merlin engine, with a pair of Sage Geddy circuits one for each bank of 6, runs as fast as I'll allow with a wooden prop in front.
 

Jerr46

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Check out my Hoglet build playlist on my YouTube channel:
I provide details of the ignition I used.
Have fun!
Andrew
Hi Andrew First off thank you so much for your video’s, love them and have learned so much from them. I am in the process of building the hoglet engine and was wondering how is the small gear attached to the crank pin? It doesn’t really show it being keyed to the shaft and I doubt that some sort of adhesive would be good enough. Thanh’s again.
 

AndrewW

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Hi Andrew First off thank you so much for your video’s, love them and have learned so much from them. I am in the process of building the hoglet engine and was wondering how is the small gear attached to the crank pin? It doesn’t really show it being keyed to the shaft and I doubt that some sort of adhesive would be good enough. Thanh’s again.
Hi
The small gear is attached to the crankshaft front end. This has a slit in the end. The crankshaft locking screw is tapered and opens up the end to fix it to the gear. Not the greatest of designs but I think it worked for me.
Good luck with the build.
Cheers
Andrew
 

Jerr46

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Hi
The small gear is attached to the crankshaft front end. This has a slit in the end. The crankshaft locking screw is tapered and opens up the end to fix it to the gear. Not the greatest of designs but I think it worked for me.
Good luck with the build.
Cheers
Andrew
Thank you for the info, I see and understand it now. Can’t wait to watch your next project.. take care.
 

dsage

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Thanks for the vote of confidence Peter195124. It has proven to be a very reliable circuit.
The info to build the ignition circuit is slowly getting buried on this forum so I'll attempt to bring it to the top.
The link below will take folks to the (current) most recent posts. If you scroll down the page to post 211 I posted the schematic and circuit board layouts. And if you read through the subsequent pages you'll find a suggested layout for a perf board layout. I can't vouch for that one but it may work and be easier to build.
I would suggest reading as much of that whole thread as possible. There is a lot of good info contained in it and reading it will answer a lot of questions.
As mentioned somewhere the complete build article is available from
Model Engine Builder Magazine Issue 34


 
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