Tony Read Posted September 18, 2012 Share Posted September 18, 2012 Been having fun with a tricycle set of electric retracts. Before I fitted them to the plane I tried the rear two together on a servo tester and they worked fine, all the time. Buoyed up by this success I connected the three together in the plane. The rear 2 have a factory fitted Y lead, so I just used another Y lead to connect to the front and to the receiver. Operating the retracts I had the following effect: All three would drop down together. The front and only one rear would pull up. Drop the retracts again. All three would pull up. This cycle could be repeated time and time again, with the same rear retract only pulling up every other time. I pulled the front retract lead off and the rear two worked fine together. I then tried all three on a servo tester and I got the three down/two up/two down/three up routine again. As I could get two working all the time I decided to connect the front retract to Aux 1 and mix to the gear channel. This has cleared the fault but what has caused this problem in the first place? Any thoughts? Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted September 18, 2012 Share Posted September 18, 2012 What make are these Tony, as I have a set of the E-flite ones for my forthcoming Apache and haven't tried them yet but will if yours are the E-flite ones too? Curious fault though.... Quote Link to comment Share on other sites More sharing options...
Chris Poulton Posted September 18, 2012 Share Posted September 18, 2012 sounds a bit like a voltage drop or a faulty connection to me, try swapping the y leads over, or a battery pack with a bit more capacity. would be interesting to see what voltage they are designed to work at, and what battery you are using. good luck. Quote Link to comment Share on other sites More sharing options...
Tony Read Posted September 18, 2012 Author Share Posted September 18, 2012 They came from Century UK and are for the Max Thrust Mig 15. I suspect they are a cheap generic set of retracts. I was using a 4s 3300 lipo in the plane and a 2s with the servo tester. I did try the two rear, then the front and one rear together with no problems. It was only when I went up to three retracts that the problem occurred. I was going to replace them with an E-flite set but the nose retract has to be buried much deeper into the foam to be hidden and I was worried about the integrity of the fuzz at that location. Quote Link to comment Share on other sites More sharing options...
GrahamC Posted September 18, 2012 Share Posted September 18, 2012 Try them on the gear channel of your radio before you do anything drastic! It might be that they don't like the graduated Input from the servo tester. Quote Link to comment Share on other sites More sharing options...
Tony Read Posted September 18, 2012 Author Share Posted September 18, 2012 Hi Graham, I've tried them with my Tx/Rx and with a servo tester, but with the same results. I thought I might be over driving the retracts so have reduced the travel on the Tx, but this does not appear to make any difference to the operation of the retracts. As I said earlier the problem was solved when I used two channels on the Rx, so I don't think it was a connection issue. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted September 18, 2012 Share Posted September 18, 2012 When I fitted electrics to my AT-6 I was testing them using an esc and LiPo and had similar problems - sometimes one worked, sometimes neither. When I swapped to a dedicated NiMh pack for them they worked a treat. I suspect they take quite a lot of current to start moving, though I've not put a meter on them. Quote Link to comment Share on other sites More sharing options...
Idris Francis Posted September 25, 2012 Share Posted September 25, 2012 You will find a great deal of information on problems with E flite electric retracts, from me and others and including link to US sites identifying similar problems, at **LINK** In brief: Lead screw drive is dreadfully inefficient leading to high currents, voltage drops, need for overload tripsn which then trip out and cause the units to cycle. Also machining tolerances have to be very good indeed due to the forces involved and there being little power/torrque to spare - and unfortunately they are not, with various parts tight and prone to stick. It became all too clear to me that mine would never be reliable, enough to fly, but as it would then have been difficult to substitute a different type removed the electric system and fitted a powerful retract servo to each unit - now works perfectly, though not yet quite ready to fly Also - I was puzzled when working on them that every time I turned the wing over the leads came apart - turned out that the fits were so slack thhat they were unsafe. Quote Link to comment Share on other sites More sharing options...
Idris Francis Posted September 25, 2012 Share Posted September 25, 2012 This one just to tick the box for notification of any response Quote Link to comment Share on other sites More sharing options...
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