Webster Engine re-design & (hopefully) build:

[lucky13dave]

Turns out we're changing that. Reason for that was for assembly.

We had made a change to the cylinder. In short we incorporated another part , and as a result the length of the portion that inserts into the frame was increased. The flywheel at this point wasn't stepped, and it's moment of inertia was too high. We had planned to remove material to bring that in.

We realized that since the flywheel needs to be installed before the cylinder, this design would be impossible to assemble. The stepped flywheel makes it possible to assemble, but it's moment of inertia was too low. The steps are essentially clearance for the geometry of the cylinder. Take a look at the top view, that's where you can see the geometries the best.

But the moment of inertia is too low now. We removed the 2 steps from the flywheel, then brought the OD down until it had the same moment of inertia of the rotating assembly from the original design. We are making changes to the frame and cylinder as well. So there will be more pics of models soon.

 

[IronHorse]

Nice job on the redesign. I to was thinking of ways to simplify the design. I am working on a version that eliminates the points. I noticed that on gas weed eaters and other small gas appliences that they do not usually use points. They "time" the engine with the coil to Flywheel magnet position. I am going to mount the coil on a moveable plate for timing adjustment. The magnets would be installed on the flywheel. With this arrangement I can save using points and eliminate external ignition parts like a battery. You would get 2 sparks per cycle, but that is how most 4 cycle lawnmowers work anyway.

IronHorse

 

[lucky13dave]

Nice job on the redesign. I to was thinking of ways to simplify the design. I am working on a version that eliminates the points. I noticed that on gas weed eaters and other small gas appliences that they do not usually use points. They "time" the engine with the coil to Flywheel magnet position. I am going to mount the coil on a moveable plate for timing adjustment. The magnets would be installed on the flywheel. With this arrangement I can save using points and eliminate external ignition parts like a battery. You would get 2 sparks per cycle, but that is how most 4 cycle lawnmowers work anyway.

IronHorse

Thanks! There are more updates to come, I'll try to post them soon.

We're planning on using a CDI ignition from CH Ignitions. I ordered one to play around with, & just received it.

Sounds like you're describing a magneto system?