Gary Manuel Posted February 2, 2015 Author Share Posted February 2, 2015 Yes Bob - I think it's one of the best colours for orientation. John Stones' Atom is also yellow and he flies at the same club as me, so that could be a problem. From reading the reports on learning to fly these things, I think it's unlikely that they will ever be in the air at the same time It would be nice to do a bit of formation flying though. The truth is that yellow is only my base colour. I intend using other trim colours on top. I'll add the trim when I've covered the tail. Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 2, 2015 Author Share Posted February 2, 2015 This is the down-side of a 3 rudder tail. Covering it took almost as much time and effort as building it. I always start with the corners because it makes the larger surfaces much easier. This is the top..... and the bottom. and the finished tail. I still have the three rudders and three blades to cover when my back stops aching through bending down for 4 hours solid!. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 2, 2015 Share Posted February 2, 2015 Mines blue + yellow they won't look anything like each other the yellow you used looks like it could have come off same roll as mine If you bet with Iqon get money down first, he has short arms n deep pockets John Quote Link to comment Share on other sites More sharing options...
Chris Bates Posted February 4, 2015 Share Posted February 4, 2015 Will 1.8kg servos work. ATB Chris Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 4, 2015 Author Share Posted February 4, 2015 I don't see why not as long as they live up to their rated torque and are metal geared. These are the servos I've used, as suggested here by Richard Harris (the designer) which are rated at 2.2kg Hobbyking 929MG 2.2Kg Metal Geared Servos You might be better asking Richard for his advice. Quote Link to comment Share on other sites More sharing options...
Chris Bates Posted February 4, 2015 Share Posted February 4, 2015 Thanks Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 4, 2015 Author Share Posted February 4, 2015 Three rudders covered using the same yellow base colour as the fuselage for now. Rudders set up in centre position with the wires nice and tight. Clevices fitted to servo end. I have chosen to cross the pull-pull wires for best geometry and to keep them out of the way. stick pushed left - wire nice and slack ..... and right - same again. I have not adjusted throws yet. These are on 100% at the moment. JR tranny goes up to 125% so it looks like I've got plenty of movement. Cowl is sprayed with a (almost) matching base colour. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 4, 2015 Share Posted February 4, 2015 Looks like a fighter/bond version Gary, like it John Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 5, 2015 Author Share Posted February 5, 2015 Top of blades coloured like this. Bottom coloured like this. Amazing what difference a bit of colour makes. I'm happy with this as it suits the pilot who is actually a Pokemon called Infernape (don't tell my son). The finished article. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 5, 2015 Share Posted February 5, 2015 Great job Gary, no problem seeing that one coming/going John Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 6, 2015 Author Share Posted February 6, 2015 As I have declared my Atom Special to be finished and the weather was pretty good today, I decided to take her to the field for final setup, taxi around the field and possibly a maiden flight if all went well. Final checks went OK - so lined her up on the field pointing directly into the wind. The wind was causing the blades to turn without any help but only very slowly, certainly nowhere near fast enough to take off. I gave the blades a bit of a turn by hand and slowly opened the throttle enough to get the model moving slowly across the field. I was in two minds whether to just taxi round for a while, or go for a take off. I noticed though, that the model was tracking true and straight and the blades were spinning faster and faster so I decided to go for it. I pulled the stick back expecting the worse, but she rose very slowly off the ground and kept flying at a nice climb in a straight line, up to about 60 feet high. I noted that I did need to hold a fair amount of up elevator in to hold level flight. I then gave a little left rudder and was surprised that it wasn't the nice flat turn to the left that I was expecting but a rather tight bank and the nose down. Must remember to put opposite aileron and a bit more up elevator in when I turn, I thought. Eventually leveled her out, now heading down wind and I noticed quite severe shaking, which wasn't there on the up wind take off. I didn't understand what was causing this and I initially thought it was the blades not balanced right - but how could it be? They were OK when flying upwind. I later worked out what was wrong - I think. I'll come back to this later and ask a question to the more experienced gyro-nuts. So here I was, flying down wind, shaking quite violently and me holding quite a bit of up elevator in. I went for another left hand turn, this time I kept it quite flat, and I noticed straight away that the shaking had stopped - strange! I did a couple more uneventful circuits (thus securing my £20 wager ) with too much up elevator to trim out, each time noticing the shaking on the downwind leg. I decided that the best thing to do was land and adjust the pitch controls. The landing was not the prettiest I've ever done. I landed on the wheels, but then tipped over as it was coming to a halt. No real damage, but one of the pull-pull threaded adapters has pulled out of the clevis. The thread on the HK adapter on inspection was not very good - looked like faulty workmanship because the lock nut also spun on it if overtightened. I decided to cyano the adapted onto the clevis and renew it when I got home. This would allow my to adjust the throws and have another go. I also loosened the blade securing bolts a bit, in case the blades were too tight and not self balancing properly, causing the shaking. Took off for second flight and after the first left hand circuit, I went to adjust the elevator trim, which still needed a bit of up. While I was fiddling about trying to find the trim, I inadvertently turned RIGHT into quite a steep banked dive. I must have accidentally applied a bit right aileron. I tried to recover, but was unable to and my poor Atom did a nose first landing into the adjacent ploughed field. Fortunately, the ground was very soft and the only damage was a broken mast, directly above the fuselage, a broken prop and a damaged cowl. I see the broken mast as being a GOOD design feature, because it prevented damage to other more expensive / difficult parts. I have now cleaned the model up and am happy that all I need to do is replace the mast and make a new cowl (or leave it off). Back to the question about shaking on the down wind leg. I think it may be because on the up-wind leg, all three blades would be at negative angle of attack and therefore reasonably balanced. On the down wind leg, the blades may have been alternating between positive and negative angle of attack as they cut into / against the wind. My question to the gyro-nuts is, is this normal behavior, or am I doing something wrong? Edit - typo's corrected Edited By Gary Manuel on 06/02/2015 19:53:09 Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted February 6, 2015 Share Posted February 6, 2015 Gary, Well done on the maiden , you are a brave man to carry on flying with up stick held in to maintain a level flight. Try slackening your blade mount bolts off a little, you should be able to move them easily with the just a bit of resistance. A classic sign of a blade/blades mounting bolts being a touch tight is a 'wobble on' as the blades slow down on the down wind leg. Rich Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 6, 2015 Share Posted February 6, 2015 Glad it's not too serious Gary quick fix so you'll soon be back. I have some hardwood if you've none left. John Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 7, 2015 Author Share Posted February 7, 2015 Thanks Rich. I will slacken them off a bit more to see if the wobble reduces. Another advantage of the Mk2 flex plate is that you can get your finger onto one of the flat surfaces to spin the blades up rather than having to go on the actual blade. This probably allows blades to be a bit slacker. I'll let you know right here how it goes after the next flight. John, It'll be fixed on Sunday. I have plenty of spruce left for the mast thanks. Hopefully yours will be ready by the time I fly again, so we can do some formation taxi-ing. Gary. Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted February 16, 2015 Share Posted February 16, 2015 Gary, if you fly it in a light breeze you won't need to spin the blades by hand at all! Check all nuts and bolts for tightness, especially after experiencing some vibration, and if any are loose undo them a little and apply a bit more threadlock. Helis literally shake themselves to pieces through similar vibration if not checked! Re-maiden soon? Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 16, 2015 Author Share Posted February 16, 2015 Chris, It's ready to Re-maiden as soon as I get rid of this cold and right weather presents itself. I know what you mean about not needing to spin the blades up in a breeze. On the day I did the maiden flight, it practically flew out of my hands when I pointed it into the wind and slightly tipped backwards! I'll take this opportunity to post a couple of post-maiden pictures. This is the model after a bit of a clean up. This is the bit that had the main damage. I like to think that this is working as designed, as it prevented further damage. This is cosmetic but not re-usable. Easier to make a new one as I still have the plug. Here is the rebuilt model with a new mast and cowl - ready for a review of the centre of gravity and final adjustments to control geometry before I have another go. I have slackened the blade bolts off a bit as suggested by Richard. I'm going to pick a really calm day next time, to take one of the variables out of the equation and give me more time to analyse what's going on. Quote Link to comment Share on other sites More sharing options...
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