Some more thoughts to muddy the water: Yes, Large diameter , heavy flyweheels can be turned slower and yes, you can power them with a "small engine, however, a flywheel by nature, starts slowing down as soon as it starts to do any work. The engineering formula for them uses a no load speed and a speed when they have completed their task, and the percentage one to another determines the "capacity" of your system. Large heavy wheels have tremendous initial force, but they still slow down, and herein lies the rub. You need a decent "recovery" time. If your wheels take 10 seconds to spool back up once you have split a log, then your split time savings become pointless. If you do not let your wheels recover, you just keep going slower and slower.And the your recovery time will be long indeed. So if you use a big wheel, and you want fast recovery, you need horsepower. If you use smaller wheels and spin them faster, you will lose much more rpm as you perform your task, but your recovery time is short. However your cycle times become ( in my opinion) too fast unless you use some sort of reduction. I have a friend who is into antique tractors big time. Some of those old steam tractors have flywheels that are 6ft. across and turn so slow you wouldn't think they would do anything, but their rim speed is tremendous. What a log splitter they would make!!
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