This one I actually put a bit of planning into. It has three cylinders, all vertical, all joining the axle at 120 degrees to each other. I started planning this model as soon as the prototype was finished, because the prototype wasn't really satisfactory, and built it the next day. It doesn't bend under the stress and at full pressure the cog is very difficult to stop by hand. Also, it runs much more smoothly than the previous one, although it is still a little jerky.