I figured I'd post a follow-up on this project now that I have been using it a little more than a year. I have put a good many hours on this thing now and am just thrilled with how well it works and how useful it is. It was critical for running the compressor while we framed up a new garage (remember this place is off-grid). One of my favorite features is the ability to increase the engine RPM a little with the middle-sized pulley. This gives me the ability to super charge tools as needed. In other words, if I need a little more power out of an electric power tool, I can tweak the voltage up a little higher by giving the engine a bit more throttle. I have pushed it up to 150 volts without any issues. Sure, it also increases the frequency, but that's no issue. I have a small portable Hitachi table saw that runs fantastic at 150 volts. I know, I'm taking some risk that I could burn out the motor, but I'm willing to experiment and live with that risk. What I know so far, is that the saw cuts like my larger 2hp table saw does running on grid power wired for 220 volts. The Hitachi running at 150 volts has shown no sign of motor overheating, or any other issue. The middle sized pulley will run anything I need, and if it struggles, then I give it some additional RPMs, but I never go over 150 just because that's the limit I have set, and the meters on the generator don't go much higher than that.
The only downside to the design is that it hangs off the front of the tractor and is quite low to the ground. One time I wasn't paying attention while I moved the tractor, and cracked one of the wood frame members. I fixed it and it's like new again.
This summer the generator failed and I found that the capacitor inside had died. Picked up two new caps (now I have a spare) on ebay and it's back to life now.
