Some of my self-made machines.

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I uploaded a video of my No. 3/2024 Hit & Miss engine "Musa-Retrol HM 01) today.
Unfortunately, the file is too large to show directly here.



I have slightly enlarged the central bore in the carburetor so that the engine can be operated with the cap closed in miss mode. To run at full speed and continuous ignition, you only need to move the blocking lever for the breaker and open the throttle cap a little.The engine starts very easily.

The engine runs with a mains connection for the ignition, but can also be switched to battery power.
 
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That is an impressively slow engine in hit-and-miss mode, especially for a small engine.
Everything is finished out very nicely !
Nice looking and good running engine.
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Yes, I like it very much. But I had a few problems with the contact ignition at first. These original contact plates were very difficult to set so that the ignition was triggered at the right time. I removed these contacts and fitted a microswitch. I also fitted a holder with an adjusting screw to the control rod of the exhaust valve. This allows the ignition timing to be set very precisely.
 

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If you want to retain the vintage look, you could crack one microswitch open and mount the internals on a phenolic piece. Not sure if that is a "Schnapsidee" :) At least it would not be too expensive to have a look what is inside. :cool:
 
If you want to retain the vintage look, you could crack one microswitch open and mount the internals on a phenolic piece. Not sure if that is a "Schnapsidee" :) At least it would not be too expensive to have a look what is inside. :cool:
Whether I use an open switch, Hall sensor or micro switch on a model motor like this doesn't really matter to me. What counts for me is the safe function at the end of the assembly.

Other owners of the HM 01 engine had the same problems. These two original reeds can only be adjusted correctly by bending them. However, this can only be done when the engine has been removed.

You have to make compromises with such small engines. I don't think anyone would install a magneto ignition on this scale.


On another motor there are two Spring contacts, or a Hall sensor.
 

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