If you are wondering why this hub failed, you might consider how you are using it compared to what it was designed for. These ball bearing hubs were designed for 26-28" diameter wheels that travel at a maximum or 50 mph or 1880 to 2030 rpm. If your winch retreives at 30 feet per second this means that the hub with its diameter of .58" must spin at 11,900 rpm. This might explain why they are so noisy. Although the radial load is a lot less in this application, I think the speed is a bit over the design expectations, don't you.
Tim Bennett ----- Original Message ----- From: "James R MacLean" <[EMAIL PROTECTED]> To: <soaring@airage.com> Sent: Monday, March 21, 2005 7:53 PM Subject: [RCSE] Retreiver bicycle sprocket > Sunday our club is having a monthly contest and this time it is > sailplanes. I have been promoting glider flying in our club for about the > last five years and the club contests now draw about 20 souls who are > getting much more competent with their planes. It was a nice day and no > one broke anything. Most made their times and all had a good time. > > But, on saturday we checked out the equipment and the retreiver bicycle > sprocket bail was broke! This is a Rham retreiver which has given us > good service for about five years. No problem I think. Just go down to > Bob's bicycle shop and buy a new one. Oops. They laugh and say where > did you get that old timer! Some time later, the new sprocket bearing is > ready with their help and some luck looking in the back of some of their > junk drawers. We are OK for now. Where do you go to get an old time > front sprocket or at least some new ball bearings to rebuild the > sprocket? And the 9/16 " thin open end wrench needed to tighten the > locking nuts. > > Advice and thoughts appreciated. Jim MacLean, Melbourne, FL > RCSE-List facilities provided by Model Airplane News. Send "subscribe" > and "unsubscribe" requests to [EMAIL PROTECTED] Please note > that subscribe and unsubscribe messages must be sent in text only format > with MIME turned off. Email sent from web based email such as Hotmail and > AOL are generally NOT in text format RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
