January 10, 20196 yr Author Finally, yesterday I received the 3rd pack of the 4 I ordered for the contest. Unfortunately there is no chance to receive the 4th pack before Monday, which contains important bent liftarms and all the 3L red axle-pins necessary for the chassis. Anyway, I couldn't wait any more, and yesterday I started to build the aircraft. Some modules and attachments could be built, but there is no way to start the main body before next week. Anyway, at least I have something from real bricks. So far I had to make only little adjustments. On 12/17/2018 at 12:10 PM, Rudivdk said: I worry a bit about possible slack in the control system due to the gears, u-joints and long control axles. On 12/24/2018 at 2:20 PM, Xewyz2001 said: However, as Rudivdk mentioned earlier, there is going to slack owing to the cardan joints, even one of them introduces a slack of a few degrees, and adding the slack from the gear systems most probably will reduce the movement angles a bit. On 12/22/2018 at 5:45 PM, Erik Leppen said: One thing that I'm slightly worried about is the sharp angle of the universal joints used at the sides. They might introduced a lot of slack, and make the rear azure-color-coded control surfaces "hang" or make their movements jerky. I hope that in reality it's acceptable. I also tested some functions with real bricks. I did not understand, why all of you earlier said, that the u-joints will introduce a lot of slack. I never experienced that, however, never used them in such a sharp angles as in the wing. I could not test it earlier, because all of my u-joints were built in to a models I didn't want to disassemble yet. But yesterday I tested the u-joints, and now I understand why you said it could be problematic and could introduce a lot of slack... A u-joint alone, bent in 53 degree suffers huge wobbling. Then I built a test frame copying the same geometry how the u-joints are used in the wing, and interestingly I didn't experienced any slack. Any control turn resulted in immediate reaction at the other end. I don't really understand it yet, but happy with the result. The controls will probably work. I will know more at next week.
January 17, 20196 yr Author Aircraft completed. Unfortunately the controls are limited by the tight cabin interior, but otherwise works as expected. It was a real pain to set up and center the elevon system, took at least four hours. It is very hard to access the gears, and the slack had to be counted in when setting up each gears cog-by-cog precision. Gravity applies constant torque on the control surfaces (same for landing legs), which turns all the control rods, gears and u-joints relative to the designed reference position and consumes all the slack. When I positioned the gears so that this tilt is counted, then the control system started to work fine with minimal slack. The aircraft is larger and heavier than I expected, so a stand is a must have, otherwise I won't be able to show the functionalities and make a video. And making much better images. But I still have one month until the deadline.
January 17, 20196 yr I like its current flowing form. I do think it should be a manual system for VTOL system though. Only my preference.
January 31, 20196 yr Author OK, the deadline is closing so I completed a stand and make some better photos. See more in my flickr album The rotor is spinning, ready to take off. No compatibility issues between PF and the old 9V system, converter cable works fine. I also tried to take a photo about the spinning front propellers, but they are spinning faster, and completely homogeneous black, so they just appear as a slightly darker spot before the background (quasi invisible). I already completed the 3 entry photos as well, but will only publish when submitting the aircraft to the entry topic. Only one bullet point left: the video. Definitely my biggest weakness...
January 31, 20196 yr Very unique build, wasn't sure about its feasibility at the beginning, and now I really like it! You have my vote for sure.
February 1, 20196 yr Excellent, this is one of my favorites. I can't wait to see the video with all of its functions.
February 10, 20196 yr You chose a very challenging design to try and replicate in Technic. The final result definitely beat my expectations on how it would be achieved. Really nice video for the competition entry. Edited February 10, 20196 yr by nigel1975
February 12, 20196 yr It turned out very nice! Really beautiful flow in the bodywork, and a good and realistic set of functions! And your presentation is pretty as well, love the pics and vid This contest is getting better and better
February 12, 20196 yr While this model is well built and intricate, there is on thing wrong with the tail. The Elevon Roll is backward. The Picture below is how it should look.
February 12, 20196 yr Author On 2/12/2019 at 10:00 PM, Aventador2004 said: While this model is well built and intricate, there is on thing wrong with the tail. The Elevon Roll is backward. The Picture below is how it should look. Yes, true. There are two ways to do it correctly. Either, one of the 20t gears on the side has to be driven instead of the middle one, or the differentials have to be reversed. Both solves the problem. Kind of... Because driving the side gears causing slack on the other side (works correctly, but not too elegant). Or reversing the differentials, but then the middle 16t gear can sometimes stuck with the edge of the 28t differentials (so its not reliable), or the middle gear can be changed to a half conical 12t gear, but it can sometimes slip/jump (so its not reliable). I tried all the versions, and the decision was to use the backward roll. Maybe not the best decision, and driving a side gear would be better, like on this old concept from the beginning of the topic. Unfortunately there is no perfect solution, at least I couldn't find one.
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