Martyn K Posted November 11, 2019 Share Posted November 11, 2019 I am going for a rudder and now having third thoughts about flaps. I'll probably not bother though as its quite a draggy airframe Yep - Crow is as you described - an effective lift and speed shedding formula Martyn Quote Link to comment Share on other sites More sharing options...
Martin Gay Posted November 11, 2019 Share Posted November 11, 2019 I would recommend fitting the flaps. Yes, it is a draggy airframe but it is also a quick model. Just because you have them doesn't mean you have to use them all the time, however, once you get the hang of using CROW (flaps down and ailerons up), you will be happy you have them fitted. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 11, 2019 Author Share Posted November 11, 2019 Thanks chaps, obviously this all adds complication and additional servos..... all increasing the wing loading. But I appreciate you sharing your experience and will do as you suggest. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Martin Gay Posted November 12, 2019 Share Posted November 12, 2019 A couple of 13g servos and linkages will not increase the wing loading by much. The prototype Sabre was 4lb in weight and roughly 2.78 square feet if wing area which works out to be 23oz per square foot wing loading. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 12, 2019 Author Share Posted November 12, 2019 Hi Martin, you are talking to someone that is fanatical about saving weight I hope to use RDS for both the flaps and the ailerons, possibly even the rudder too. never used RDS for a rudder this model should prove a good platform to try that and my new 3D printed RDS adaptors. I noticed on Daves Sabre thread you talked about stencils, if anybody does the Luftwaffe Sabres I am happy to share the masks I cut, if it helps somebody else Put in my SLEC order today, not quite as cheap as I expected, but what the heck, you can't take it with you..... Cheers Danny Quote Link to comment Share on other sites More sharing options...
Flyer Posted November 12, 2019 Share Posted November 12, 2019 Hi Danny, Any chance doing a few post about the RDS adaptors; I'm sure this would be useful. Especially as quite a few of the lads have access to 3D printers. Cheers Ade Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 12, 2019 Author Share Posted November 12, 2019 Hi Ade, yes sure. I actually get a friend to print them for me as I haven't taken the plunge yet. But the beauty of this design is that they will fit any servo and are not restricted by spline size/type. Should be able to mount all four servos in the wing root, with the RDS rods at 45 degrees to the surfaces. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted November 13, 2019 Share Posted November 13, 2019 How robust are the RDS adapters Danny? I have found that PSS models tend to get more abuse due to the less clinical environment compared to a neat flying field. Assembly of models is usually out the back of the car and landings can sometimes be better described as ditchings, especially in heather and clumpy grass! There is an RDS adapter on Thingyverse here. Is that anything like yours Danny? Quote Link to comment Share on other sites More sharing options...
David Sack Posted December 21, 2019 Share Posted December 21, 2019 Hi Guys, I want to go down the RDS route too. The only accessible versions I found were on the Graupner site. https://www.graupner.com/RDS-Servo-lead-duct/JR/3925/ A bit pricey perhaps, especially with postage. This seems to be the right size but I am no expert and was hoping to tactfully, but unashamedly, follow someone elses experience. If someone is printing these adapters and sharing - count me in ! Edited By David Sack on 21/12/2019 08:40:27 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted December 21, 2019 Share Posted December 21, 2019 RDS are used quite a bit in the F5 / F3 areas, have a look on Hyperflight Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted December 21, 2019 Author Share Posted December 21, 2019 This is my implementation. I have got some 3D printed adaptors for the servo output arms. The bit that will wear and cause slop is the torque box. I line mine with melamine so that it is very hard wearing. Maybe this will help? Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted December 21, 2019 Author Share Posted December 21, 2019 A friend (Eric Strefford) is printing these for me. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted December 21, 2019 Author Share Posted December 21, 2019 The problem with commercial RDS adaptors is that they are manufactured to fit specific servos, more accurately their splines. These that I use are universal and bolt onto a supplied cross output arm, which virtually all servos come with. When set up correctly they are very robust. But be aware of the weight, the longer the piano wire the more weight you are adding, so short lengths are good. I make the bearing that the torque rod rotates and passes through, out of hardwood, not metal to save weight. Cheers Danny. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.