Kilo3D Prototype 1 Pre and Post Flight Briefing Tagged with: 3D, Aerobatic, Building, Designing, Kilo3D, Video, XPS Saturday, May 12th, 2012 08:51 am GMT -7 Saturday, May 12th, 2012 08:51 am GMT -7Saturday, May 12th, 2012 08:51 am GMT -7 I finished building the Kilo3D first prototype and then flew it. Share this: Recommend on Facebook Share on Google+ Tweet about it Tell a friend Related posts: Kilo3D Prototype 1 Build Kilo3D Prototype 2 Wing Build Kilo3D Prototype 2 Planned Changes Foam Model Airplane Wing Spar Design Kilo3D Flight 2 and Briefings Kilo3D Part 1: Goals and Background Kilo3D Part 4: 3D Training Videos Kilo3D Part 3: Design Refinements Kilo3D Part 2: Preliminary Design Pickerel Flying Video 2 Is Foam Better than Balsa for Building? Introduction to RC Airplane Foams Logging In... Add Comment Register Profile cancel Sign in with Twitter Sign in with Facebook or Name EmailNot published Website Comment Sure! Also send me the free email newsletter. 2 Replies 2 Comments 0 Tweets 0 Facebook 0 Pingbacks Last reply was Sunday, May 13th, 2012 07:37 pm GMT -7 mjcmyers View <abbr class='timeago' title='2012-05-14 01:19:18Z'>Sunday, May 13th, 2012 07:19 pm GMT -7</abbr> Check out this video I made of my servo problem I had on a DT foam 3D plane. http://www.youtube.com/watch?v=4YLbuQP8HZ4 I posted it to RCGroups looking for help and actually had every reason you suggested as the potential problem. I have never had this happen on any plane before or after this one. Go figure? Carlosreplied: View <abbr class='timeago' title='2012-05-14 01:37:42Z'>Sunday, May 13th, 2012 07:37 pm GMT -7</abbr> That is exactly the problem I ran into! I had never seen that or heard about that, either. It looked to me like a self-induced flutter. With Kilo3D, I started out by using the tiny (3.4 g) BMS-303 servos. I had the jitter on the rudder and flaperons, just like you. These are analog servos with poor centering, so I figured that must be the problem. I switched to 6 gram digital servos, which were much better, but were still jittering. Then I switched to Cirrus 5.4 servos (also about 6 g), which were almost okay, but one of the flaperons would still jitter once in a while. That is the point where I was when I shot this video. I thought the problem might be slop in the control linkages. I cut the control rod length in half, but that hardly made any difference. I then decided to bring in the big guns. I installed Hitec HS-86BB+ servos on the flaperons. These weigh about 20 grams and have about 40 oz-in of torque. This is about twice as much torque as the other servos. Problem gone! These are rock solid. My conclusion is that the smaller servos just were not strong enough to maintain the position. These are relatively heavy control surfaces. The mass of the control surface would start an oscillation that the servo just could not tame. Thank you for writing! At least I am not alone!