Quote from: k4zep on July 05, 2008, 09:27:54 PM
That motor setup was NOT a failure, look what you learned!!!!!  Most impressive........I bet your next one WILL work....That 35 degrees AFTER TDC looks more and more like a viable setting.

Ben

Hi Ben,

Thanks. Yes there is much more to learn about applying this process to get a real combustion engine working. One thing I just remembered regarding why the initial normal ignition spark can be dampened to the point of not being able to be strong enough to discharge the capacitors in the discharge circuit. Years ago I did a great deal of high voltage discharge testing in a vacuum chamber. A HV low current spark such as that from an ignition coil is incredibly strong and can travel far greater distances in a vacuum. This is because there is no air and air can be insulative to the high voltage. So from this understanding it does make sense that we have quite the opposite effect going on in the cylinder of a cumbustion engine. It seems the pressure of compressed air will dampen the ignition spark and this can create problems for the discharge circuit being able to discharge. So once again, this analysis does back up the idea that a stronger ignition pulse will be required for this process to work in a combustion engine. This may mean that most people may have difficulties if trying to apply this process to an unmodified magneto type of ignition system.

Regards,

Ossie

Maybe it's best that experimenters get their electric circuit refined to the point where they can blow up plastic bottles first - that would be easier, and more encouraging than trying and failing to get a motor going.  Proof of a powerful expanding pressure would mean that the engine designs are just a design issue. 

Bumfuzzled - your ignorance on things electrical is likely to be a self-fullfilling prophesy.  You can chose to "ignore" the wealth of knowledge all around you, or you can chose to start learning.  At the very bottom if you must - but don't blame your ignorance an anything other than your own choice.

Ignition timing is going to be a big issue for most experimenters.  It might be an idea to forget the conventional ignition circuit and build a new one.  Perhaps an optical sensor that can detect a 

Went to my dad's and found a very old Kohler 8 HP lawnmower that is battery ignition with points and a regular canister style coil. So this will be my new test mule if I can get it to run on gasoline first, it's really old. At least I can reverse the polarity on the coil on this one and see what happens.

Ossie, when you say point the diodes toward the magneto does that mean the flow of electricity should go to the magneto or be blocked from going to the magneto?? Seems like I tried that with a string of diodes but I can't remember at the moment.

Quote from: greendoor on July 05, 2008, 10:37:25 PM
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Bumfuzzled - your ignorance on things electrical is likely to be a self-fullfilling prophesy.  You can chose to "ignore" the wealth of knowledge all around you, or you can chose to start learning.  At the very bottom if you must - but don't blame your ignorance an anything other than your own choice.

Hey at least I'm out there trying to figure this out instead of sitting behind a keyboard criticizing people who are actually trying to get things going. If you'll read up a couple posts you'll see the man that came up with the circuit that I'm using had trouble getting it to work on an engine too at first. Are you an electronics wizard? If so did you learn it overnight? You know how long I've been learning about electronics? About a week now so unless you have something useful to say to me then please leave me out of yer posts.

Some thoughts on the 4 stroke single cylinder engine:

The ignition pulse comes from the magneto.
This creates a voltage pulse with EVERY single revolution of the output shaft.
Every 2 strokes of the piston completes 1 revolution of the engine.
There are therefore 2 ignition pulses to every 4 strokes of the engine.
This creates what is called a "waste" spark. This is not a problem for a gasoline powered engine.
That is because of the "burn rate" of gasoline..... which is SLOW compared to hydrogen (10X faster!)

This slow burn rate is the REASON that the spark is set to occur before TDC.
It actually ignites the fuel/air mixture before the top of the compression stroke so it can complete the (slow) burn within the power stroke.
(It is, by the way, why gas engines are so inefficient... the premature combustion pushing against a piston that's trying to come up!)
It does this to create more TIME for the gasoline to completely combust.

Engines with points essentially run off the cam shaft which is turning at HALF the speed of the crank/output shaft.
The points are then set to spark only ONCE for every 2 revolutions of the output shaft (and 4 strokes) of the engine.

I think ultimately, we are going to want to take advantage of the extremely FAST burn rate of the hydrogen/plasma/water explosion.
We are going to want to time the spark to occur PAST TDC to get the most power and efficiency out of the engine...... when the piston is on its way DOWN on the power stroke.

Therefore, if we move our timing past TDC (by adjusting the magneto), we will find ourselves setting a 2nd spark to the INTAKE stroke.... very bad for valves.
The waste spark must be dealt with (imo).
@bumfuzzled
That old Kohler is a real find because of the points ignition setup, I don't believe you will have to deal with the waste spark and you should be able to play with the timing and set it past TDC..... nice score!