Belt Tension

[GreenCello]

How do you guys set your belt tension and how much tension is correct? I am working on the tail box for the first time. When I removed the left side I could see that there was a fair amount of belt tension on the shaft gear. My tail box is seated all the way forward and I guess that I need to move the boom forward and assume that the 4 screws thru the frame into the boom blocks bite into the boom. Correct?
Thanks

[rotorhead58d]

How do you guys set your belt tension and how much tension is correct? I am working on the tail box for the first time. When I removed the left side I could see that there was a fair amount of belt tension on the shaft gear. My tail box is seated all the way forward and I guess that I need to move the boom forward and assume that the 4 screws thru the frame into the boom blocks bite into the boom. Correct?
Thanks

that's right. it's not a science. just snug it, but not too tight. everything should spin freely. you just have to try it out. hard to describe on the internetz

[small.planes]

yes, the 4 screws and a little friction are all that hold the boom in.
I judge my tension by prodding it between the maingear pulley and the idler with a small screwdriver. Its a feel thing, but I think that if you hold the maingear still it should be just possible to turn the tailshaft over, so it skips a tooth. Thats possibly a little on the slack side, but you dont want it to tight, and the belt has teeth for a reason ;) The tailrotor shouldnt be stalled during flight anyway, and in a crash this tension might save a snapped belt?
no doubt there will be more opinions along shortly.

Dave

[Snoobab]

You might find this article helpful: 'Adjusting Gear Mesh & Belt Tension' http://www.rchelimag.com/pages/howto.php?howto=7&page=3 Cheers.