Hi John, I watched the videos, I feel your frustration, what you describe in taking video is what I've experienced with digital pictures, the camera takes the picture when it's ready, not when I push the button. I haven't built a solenoid engine since I was a small boy, but the inverse force/distance relationship has always been the stumbling block for electric motors of every sort, even three phase motors which have their most torque at start up, opposite that of single phase motors. I was thinking that perhaps if you allow the solenoid plunger to go past TDC, you would then have the plunger in the middle of its stroke when it has the greatest pull, and if you opened the contacts as the plunger crossed fully enclosed, and added a capacitor, the current would reverse in the solenoid at that point, and the capacitor would provide current to pull the plunger back into the solenoid, and in effect, make it double acting as a steam engine. There is no doubt that running it on d.c. is the most efficient way unless you get it running syncronous to the frequency of the a.c. current, in which case, you might be able to have the plunger go past TDC during the zero current cross-over point, and then the next "peak" would be pulling the plunger back in. I can't say I've ever tried it, but I will if I can shoe-horn it into all the other projects. A very interesting proposition though, and worthy of further investigation.
Cheers, mad jack
