I was having a hard time finding bushings that fit the tower stub so I decided to make them myself out of plastic. I did a bit of research and found that people were using Ultra High Molecular Weight (UHMW) plastic for this type of thing. UHMW appears to have a very low friction coefficient and is much cheaper than nylon or any other exotic and more expensive plastic. I figured it would also do less damage to the tower stub and frame than bronze. Here are the specs on the thrust bearing and bushings…
Thrust Bearings:
– 1/4″ Thick UHMW polyethylene plastic
– 1-1/8″ hole saw for the inner diameter
– 2″ hole saw for the outer
Bushings:
– 1″ Thick UHMW polyethylene plastic
– 2″ hole saw for the inner
– 2-5/8″ hole saw for the outer
I’ll probably use two of the 1/4 thrust bearings on top so they can rub against each other and they should last longer that way. Hopefully there isn’t too little friction though using this plastic instead of bronze. I don’t want the wind turbine to jitter back and forth seeking the exact direction of the wind. The wind turbine will apparently produce more power if it yaws less and just points more into the predominant wind. We will just have to see. Also, I’ll probably put PVC between the three bushings in order to hold them in best position. I think this plastic should last a good long time…at least between yearly maintenance. Here are a few pictures…
