Gary Manuel Posted February 3, 2017 Author Share Posted February 3, 2017 Posted by john stones 1 on 03/02/2017 23:21:17: You put loctite on as you go ? lovely control runs John Yes - apart from the bolt through the ball joint which has a nyloc nut. Quote Link to comment Share on other sites More sharing options...
Rich too Posted February 4, 2017 Share Posted February 4, 2017 Good progress Gary Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 4, 2017 Author Share Posted February 4, 2017 Made some more progress today. Wings this time - and they are whoppers! Again, it's pre-hinged, so no work to do here. Plenty of throw on them. Covering cut away from servo holes and ironed into the hole. Plenty of lite-ply for the servo screws to bite into. Draw string provided from the root to the outboard servo position, passing the inboard servo position on its way. I only needed to make one servo extension lead as the inboard one reaches the ..... ...... Powerbox Micro Match. More on this later. Output 1 used for the inboard servo and output 2 for the outboard one. Servo lead lengths are just right. The Micro Match will be fastened inside the wing, with the servo lead passing into the fuselage to be connected. The other lead is for programming the Micro Match via a USB adapter plugged into the PC. Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 4, 2017 Author Share Posted February 4, 2017 Servo arm fastened to the best servo spline not quite parallel to the hinge line. Normally, I'd adjust this on the transmitter sub-trims, but I won't do that here. The arm is straightened using the Micro Match at centre position. Very easy to do and explained very will in the instructions so I'll not go into detail here. 90 degree position marked for the centre position ....... ..... and the full deflection position. I finished up with 3 marks on each servo position - one for centre, one for full up, one for full down, presumable because the geometry wasn't quite right. The line with the cross hairs is the average position and is where I'm going to drill the hole for the control horn. Edited By Gary Manuel on 04/02/2017 21:53:33 Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 4, 2017 Share Posted February 4, 2017 I see you've left room up front then...that for the towbar Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 4, 2017 Author Share Posted February 4, 2017 Now to match the servos, but before I do that, I need to modify an extension lead to allow the servo current to be measured. I just added a big blob of solder to each end to make it easy to clip onto the cut red wire. Meter showing steady state current with ONLY THE INNER SERVO CONNECTED. The outer push rod was left disconnected at one end. The maximum current I saw was about 0.9 amps, when moving the aileron at full speed from one extent to the other with just 1 servo connected. If I get the servos balanced properly, the current should never exceed this when I connect the second one. Centre position adjusted mechanically - the bolt can easily be slid straight in and out. Before adjustment, full deflection one way suggests that the control rod is too short ..... .... deflected the other way suggests that the control rod is too long. This confirms that I have approximately the right amount of mechanical control throw. If the rods had looks too long on too short on BOTH sides, that would have suggested that I needed to adjust the length of the fulcrum by screwing the rod in or out of the threaded horn. Edit - Ignore the above paragraph. I can improve things by adjusting the fulcrum length. I'll have another go some other time now I know what I'm doing with the Micro Matches. This is where the Micro Match comes in. By holding the transmitter stick hard to one side and then pressing the "START" button on the PC, the Servo holds its position when you let go of the stick. You can then adjust the servo throw by clicking up or down buttons (fine and course buttons provided) on the PC screen until the throw is how you want it. Then press START again and the servo returns to centre. That's it - the full deflection is now matched in that particular direction. Bolt can be slid in and out nice and easily. Repeat for the other direction and you're done. Bolts can now be fitted and current carefully checked throughout the full range. I also kept my fingers on the ball link to check that it wasn't tight at any point. OK in centre position. OK going one direction. ..... and the other. The current was similar to when the aileron was being driven by one servo. I never saw the meter read more than 1A regardless of the speed I moved the sticks. I'm well chuffed with the Micro Matches. Hope they prove to be reliable. Fingers crossed. Matching pair. Edited By Gary Manuel on 04/02/2017 22:35:40 Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 4, 2017 Author Share Posted February 4, 2017 Posted by john stones 1 on 04/02/2017 22:17:59: I see you've left room up front then...that for the towbar I'm going to have a trial fit into the car before I put the rudder on. There's the option of having a removable rudder just by replacing the hinge pins by a length of piano wire. That will also mean that the rudder control rods / wire (not decided yet) will need connecting at the field prior to flying each time. I suspect that the rudder height will be a problem anyway - even if it will fit lengthways. Edited By Gary Manuel on 04/02/2017 22:35:07 Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 4, 2017 Share Posted February 4, 2017 What about the servo wires, you've some long ones in there, do they present any problem. John Edited By john stones 1 on 04/02/2017 22:38:34 Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 4, 2017 Author Share Posted February 4, 2017 Posted by john stones 1 on 04/02/2017 22:38:08: What about the servo wires, you've some long ones in there, do they present any problem. John Edited By john stones 1 on 04/02/2017 22:38:34 What problems are you thinking about John? Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 4, 2017 Share Posted February 4, 2017 I'm no lecky expert as you well know, heard many a time long leads can be a problem, and ferrite rings used to prevent glitching on servos? John Quote Link to comment Share on other sites More sharing options...
Rich too Posted February 5, 2017 Share Posted February 5, 2017 Great post on the servo matching, something I will need to get my head around, so it's good to see how it's done. Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 5, 2017 Share Posted February 5, 2017 Excellent servo matching tutorial Gary Quote Link to comment Share on other sites More sharing options...
Former Member Posted February 5, 2017 Share Posted February 5, 2017 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 5, 2017 Author Share Posted February 5, 2017 Thanks for the feedback fellas. Servo matching is very simple with these Micro Matches and is quite a bit cheaper than JR's MatchBoxes. From what I've seen so far, they are a very useful piece of kit. I must have been getting tired when I wrote this statement bit earlier..... Posted by Gary Manuel on 04/02/2017 22:23:24: Before adjustment, full deflection one way suggests that the control rod is too short ..... .... deflected the other way suggests that the control rod is too long. This confirms that I have approximately the right amount of mechanical control throw. If the rods had looks too long on too short on BOTH sides, that would have suggested that I needed to adjust the length of the fulcrum by screwing the rod in or out of the threaded horn. Edit - Ignore the above paragraph. I can improve things by adjusting the fulcrum length. I'll have another go some other time now I know what I'm doing with the Micro Matches. It is obvious to me NOW that the control rod driven via the aileron by the other servo has too much travel in both directions. All I need to do to reduce this travel is to screw the control rod further on to the control horn. It is quite possible that I may be able to match the servos by just doing this and using a regular Y-lead, without the need for the Micro Matches. The current measurement will tell me whether they are properly matched or not. I'll have a go at this out of interest, but I'll leave the Micro Matches on as they are embedded in the wing now and I don't need them for anything else. Regarding the servo extensions - they are actually only 50cm long and are twisted to minimise interference. The elevator (and rudder?) ones will be longer. As Percy says, it shouldn't be an issue with 2.4MHz. The one servo I will add a ferrite ring to is the throttle, which is pretty close to the ignition unit and HT leads. Edited By Gary Manuel on 05/02/2017 10:17:00 Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 7, 2017 Author Share Posted February 7, 2017 Next job is to decide what I'm going to do with the tail end. The main factor that will decide this is whether I can get the model into my tiny A-class Merc. I've tried to fit it in and the good news is that I will be able to fit it in diagonally, with the rudder fitted - just. The bad news is that I will have to take the tailplane / elevators off for transport. I don't mind this - far easier to fit the two elevator halves (similar to a 2 piece wing) rather than having to fit the rudder, which would involve making the servo connections on site. This is how the rudder is held in. Supplied length of piano wire just dropped in from the top and fed through the hinges. I'll permanently fasten this down later - maybe by in-setting it and ironing some covering over it? Next decision I need to make is where to mount the rudder servos. They are designed to go inside the canopy but I would prefer to mount them at the rear if the CoG will allow. I loosely assembled everything to find out where the CoG is - It's well forward and lends itself to rear mounting the rudder servos. Here's a picture of it assembled. This is where the rudder servo's are going. There is no proper hole cut out for it but ...... ..... this will do. It's larger than a servo and is an irregular shape. It is also just balsa, so it will need strengthening a bit. Servo shaped hole cut into a doubled up piece of birch ply. Ply plate glued to the inside of the fuselage. Another piece of very thin birch ply cut out with a servo shaped hole. Covered with white film ....... ...... leaving plenty of bare wood on the other side. Covering removed from around the hole. Servo plate glued in. I also squeezed a bit of filler between the 2 plates at the narrow ends where the screws will go. Not quite invisible but I'm happy with it. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 7, 2017 Share Posted February 7, 2017 Can't say as i blame you, make the weight work for you and positive control. John Quote Link to comment Share on other sites More sharing options...
iqon Posted February 7, 2017 Share Posted February 7, 2017 I`m surprised you havent used red covering I would have put the servos in the red bit Edited By iqon on 07/02/2017 20:31:17 Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 7, 2017 Author Share Posted February 7, 2017 Posted by iqon on 07/02/2017 20:30:12: I`m surprised you havent used red covering I would have put the servos in the red bit Edited By iqon on 07/02/2017 20:31:17 Red bit is too high up. Don't forget that the tail wheel needs to be driven. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 7, 2017 Share Posted February 7, 2017 Aye put em in red bit where you can see em n spoil the looks He's just jealous Gary ignore him. John Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 8, 2017 Author Share Posted February 8, 2017 2 rudder and 2 elevator servo wires run, protected and tie-wrapped into the fuselage. Rudder control horns. Rudder hinge wire sunk into the top of the rudder. I'll cover it when I'm sure it doesn't need to come off for any reason. Elevator and rudder controls all working. I used a MicroMatch on the rudder to get them working in sync. Canopy glued to the canopy frame. I didn't bother with a pilot due to the tinted canopy. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 8, 2017 Share Posted February 8, 2017 Frightened his head would fall off again more like John Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 8, 2017 Author Share Posted February 8, 2017 Posted by john stones 1 on 08/02/2017 18:29:45: Frightened his head would fall off again more like John As far as I know, that problem is confined to Seagull Model pilots. Quote Link to comment Share on other sites More sharing options...
Rich too Posted February 9, 2017 Share Posted February 9, 2017 How long is the fuse Gary, around 100"? And how did you get the zip ties in the rear of the fuse ? Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted February 9, 2017 Author Share Posted February 9, 2017 Fuse is about 90 inches, wingspan about 107 inches. The fuselage is wide enough to shove one arm down. That's how I did the tie wraps, with a little difficulty for the furthest two. I clipped a mini-clamp onto the former, passed a long tie wrap through it, then through the hole in the former. This held the open end of the tie wrap in place for me to thread the other end back through it. Quote Link to comment Share on other sites More sharing options...
Rich too Posted February 9, 2017 Share Posted February 9, 2017 Does that include the rudder and spinner? Quote Link to comment Share on other sites More sharing options...
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