steve9534
Key Veteran
Location: yakima, wa.
| Belt drive?I asked Curtis about this once, and his response was that a belt drive would slip. I've personally had some problem with every belt tail drive heli I've owned except the last Freya. Most would slip. I had a couple from 15 years back that broke the belt. The Vigor belt didn't break, but the t/r output shaft did when I got the belt tight enough so it didn't slip too much. The first Freya I had slipped the belt, but only after a lot of time. I sold it, then bought another when I was offered a great deal on an used one. On this last one I've run the belt pretty tight, and it's not slipped yet after 30 flights or so. The new belts are clearly stronger than the old Hirobo/Legend belts were, and the Freya has a numerically high t/r gear ratio that reduces the torque loads. This may be the magic combination, but if I were to design one, I'd do the front like the Raptor 50 - simple, light, and the larger pulley in front has enough teeth engaged with the belt that it will never slip. The rear I'd do like the Shuttle which uses an idler pulley to allow the use of a larger driven pulley, again allowing the belt to engage more teeth and reduce the risk of slippage. I'd also use at least a 5:1 ratio of main shaft to t/r shaft speed. I'm not so sure that an even higher ratio wouldn't help the tail holding power, allow the use of shorter t/r blades that would be less affected by side winds, and further reduce the load on the belt/shaft. steve. |
Been lookin at 90s for a while.
