Maurice Lester Posted November 30, 2017 Share Posted November 30, 2017 I have just completed this model and on final assembly cannot get the motors to run although all other controls work correctly. Before adding final sheeting each wing was checked and everything worked including motors.Since each motor has its own ESC all four sets can't be faulty the problem seems to be 'common' and therefor in the fuselage. I assume it can't be a faulty throttle channel on the Rx because all other channels work ok. There are no beeps from ESC's which suggests no power is getting through.Wiring has been checked several times and is ok with no crossed cons. Does anyone have any suggestions? Another issue is rudder deflection. TN plans say this should be 40mmm which seems a lot but his build blog says rudder control is very important in flight.With the small servo's used movement is only about 20/25mm unless I cobble together a longer arm for the servo which may result in other problems! Any comments from flyers of this model would be much appreciated Maurice Lester Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted November 30, 2017 Share Posted November 30, 2017 Have you tried closing the throttle trim before connecting the battery? Did you check the motors individually or all at once before adding the final sheeting? Does each ESC have its own BEC - have you disabled the BECs? First things that spring to mind. Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted November 30, 2017 Share Posted November 30, 2017 Like Piers says, trim the throttle down To continue, if the props are fitted, then tether the model firmly, or better still, take the props off Now try reversing the throttle, and again trim down, way down Quote Link to comment Share on other sites More sharing options...
Maurice Lester Posted December 1, 2017 Author Share Posted December 1, 2017 Thank you both for advice - unfortunately there is no change! The wings were built first and one at a time with each pair of motors being checked together along with the other controls before the wing was sheeted At this stage the Rx and fuselage gear was a loose temporary mockup for the test. BEC's in the ESC's were disabled with a separate "fuselage" BEC supplying the Rx. Direct battery power is definitely onto each wing and I have no reason to think it is not reaching the ESC's although I do not have access to check at present without some surgery - this may be the only option if all else fails. Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted December 1, 2017 Share Posted December 1, 2017 Stick to 40 mm rudder deflection Maurice, as this amount is not much when you consider 6 foot wingspan and 4 motors. Assumption now is one exit from your RX to the motor controls. If there is just one extension From the RX to Y leads then this lot needs checking by some form of substitution Quote Link to comment Share on other sites More sharing options...
onetenor Posted December 1, 2017 Share Posted December 1, 2017 #Are you using Y cons ? Check for breaks under the insulation.I use a little mini screwdriver type thing with a window and 2 little buttons. Run it along the wiring with all live and a lightning flash shows in window which disappears when you come to break..There are various types available look on market stalls for them or in hardware / electrical shops in arcades etc.Very cheap and very handy as it reads voltage as well if you touch the tip to a contact point.Best 50p I ever spent. Quote Link to comment Share on other sites More sharing options...
Allan Bennett Posted December 1, 2017 Share Posted December 1, 2017 I don't think you've mentioned what radio gear you're using. I have read of some instances where receivers have been unable to supply enough signal strength to operate 4 ESCs Y-leaded into one channel, even though they work perfectly with 1 or even 2 ESCs. If that's the case, the answer is to use more than one channel for the throttles. So try your motors in pairs first, and see if that works. Quote Link to comment Share on other sites More sharing options...
Maurice Lester Posted December 2, 2017 Author Share Posted December 2, 2017 Many thanks for the advice guy's. Radio gear is Spektrum via a DX9. I need to do some shopping for bits before I can continue! Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted December 2, 2017 Share Posted December 2, 2017 Can you check each motor with a servo tester? That should at least tell you whether or not the connections in the wing are sound. Quote Link to comment Share on other sites More sharing options...
Robert Parker Posted December 2, 2017 Share Posted December 2, 2017 Hi Maurice, I have had the exact same problem when I built my Short Stirling. I traced it back to a faulty "Y" lead. The TN Lancaster flies like a trainer. On her maiden flight I was doing low passes and she felt very stable. I', not sure if I managed to get 40mm travel with the rudder. after all it is a bomber which does need rudder in the turns to get a scale like turn. Are you using the 4 max power setup or something else. Having built a few multi-engined aircraft I make sure I can get at all of the connections via hatches after learning the hard way. My TN Lanc is awaiting major repairs after coming in with a massive power loss which resulted in a very heavy landing ripping out the u/c and breaking 3 of the nacelles. Here she is on her maiden flight Hope to been of some help Regards Robert Quote Link to comment Share on other sites More sharing options...
Maurice Lester Posted December 2, 2017 Author Share Posted December 2, 2017 Hi Robert, Thanks for info - yes it's a 4 max setup and from comments so far it is looking more and more likely to be a problem with multiple Y leads in some form. I will go with the 40mm travel or as near as I can get. As built the plan only allows 30mm so in addition to longer servo arms I also need to trim off the elevators. As you say 'experience counts' - this is my first multi and if I build another it will certainly have more access! Hope my Lanc looks as good on its maiden, Quote Link to comment Share on other sites More sharing options...
Maurice Lester Posted December 3, 2017 Author Share Posted December 3, 2017 YIPEEE!!! Hi all. - it now all works ! Problem was with the Rx/ Y lead combo. Having ditched one Y and connected each wing into its own "throttle" channel all motors now work. I would never have thought of this solution myself so live and learn as they say. Thank you all for your help. Quote Link to comment Share on other sites More sharing options...
Rob Ashley Posted December 12, 2017 Share Posted December 12, 2017 Hi Maurice, Has she flown yet? Quote Link to comment Share on other sites More sharing options...
Maurice Lester Posted December 12, 2017 Author Share Posted December 12, 2017 Hi Rob, Not flown yet! Although build is complete I still have to finish the painting, detailing, and balancing etc. Not much time at moment with Xmas in the way! Will keep you posted in due course. Quote Link to comment Share on other sites More sharing options...
eflightray Posted December 12, 2017 Share Posted December 12, 2017 Posted by Maurice Lester on 03/12/2017 13:05:42: YIPEEE!!! Hi all. - it now all works ! Problem was with the Rx/ Y lead combo. Having ditched one Y and connected each wing into its own "throttle" channel all motors now work. I would never have thought of this solution myself so live and learn as they say. Thank you all for your help. If using separate channels for each side, you could always add differential throttle, (mixed with rudder, but preferably switch able on or off), for good ground steering. I did on my scratch built Lanc, (but then I didn't fit a steering tail wheel) . Ray. Quote Link to comment Share on other sites More sharing options...
Maurice Lester Posted December 13, 2017 Author Share Posted December 13, 2017 Thanks for the suggestion Ray. I have fitted a steerable tail wheel so should be OK. Quote Link to comment Share on other sites More sharing options...
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