As suggested in the RDS website http://www.proptwisters.org/rds2/, for heavy duty applications, and I would consider DS just that, Walt Dimick's hardened and tempered drive shafts would be best-suited. If you really want precision, use the matched pockets. When we were working this out together, we found that 1/10,000 of an inch made a difference in getting the perfect fit.
For my own use, in traditional thermal ships I get along fine with 3/32" stainless steel shafts I bend and pockets I made up as the website shows. However, where only the best will do, or where you just prefer to buy things ready to use, Walt's accessories can't be beaten. Andy Smith wrote: > I have made an EPP slope plane that uses RDS. It is 1.4 m span uses a SD6060 > and has a good turn of speed. The wing has a carbon spar (Arrow Shaft) > mounted close to the bottom of the wing with the servos (HS85mg) mounted > just behind.( The spar is about C of G) The drive shaft runs in a tube just > over the spar. To date I have not had any issues. I find the system works > very well and has less slop than typical systems. > > I suspect if you build the plane to withstand the DS loads an RDS will be > fine. > > If required I can send some pictures. > > > Andy Smith > > > > >From: Steve Witt <[EMAIL PROTECTED]> > >To: sloppymoeley <[EMAIL PROTECTED]> > >CC: [EMAIL PROTECTED] > >Subject: Re: [RCSE] RDS in EPP > >Date: Sun, 24 Mar 2002 21:40:39 -0800 (PST) > > > >On Sat, 23 Mar 2002, sloppymoeley wrote: > > > > > I am about to start construction of an EPP foam plank/wing for > > > dynamic soaring. I was considering using the Rotary Drive System on > > > the elevons to keep drag to a minimum and help protect the servos > > > from damage. However, I think that the EPP may not provide a rigid > > > enough surface to mount the servos to as the "squishiness" of the > > > foam may allow some rotational play. This play might cause some slop > > > and flutter. > > > Has anyone had experience with this system in EPP airplanes? How > > > were the results? > > > Thanks for your time, > > > Joe Morley > > > >I've never used an RDS system, but I've built 7 or 8 EPP airplanes with > >wing-mounted servos. I'm not sure why the torque developed in a servo > >twisting an RDS linkage to the elevon would be any different from the > >torque developed in a servo pushing a conventional control rod. If there > >was no (or small) friction in the RDS linkage and the elevons were hinged > >similarly, it would seem the same force would be necessary to deflect the > >elevons, resulting in the same torque back at the servo that the wing > >would have to resist. > > > > > >RCSE-List facilities provided by Model Airplane News. Send "subscribe" and > >"unsubscribe" requests to [EMAIL PROTECTED] > > > _________________________________________________________________ > Send and receive Hotmail on your mobile device: http://mobile.msn.com > > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
