Fylingdales Flyer Posted October 22, 2017 Share Posted October 22, 2017 Having flown my electric powered Ben Buckle Mini Super only once, I have decided to convert to four channel by adding ‘barn door’ ailerons. I ordered a pair of, what I thought would be suitable, servos from Servo Shop, but inadvertently ordered micro servos instead of Mini servos. The Futaba S3114 servos that arrived yesterday seem to be very small and I don’t think that they are suitable. Anyone care to comment? I do have a pair of unused older Sanwa SM-411 Mini servos, which look about right. The plugs don’t fit the sockets on the Futaba ‘Y’ lead, but I can change to a Futaba plug. Question is, will the Sanwa servos operate OK with the Futaba receiver, given that Sanwa use a different pulse length? The wiring colours on the Sanwa servos are different i.e red,black,black. How do these match up to the Futaba black red white? Graham Edited By BayNavigator on 22/10/2017 23:56:14 Edited By BayNavigator on 22/10/2017 23:57:35 Quote Link to comment Share on other sites More sharing options...
Nigel R Posted October 23, 2017 Share Posted October 23, 2017 From memory, analogue servos just average out the pulse train to get a position signal. So they should work. Sort the polarity on the plug, connect up and find out... Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted October 23, 2017 Share Posted October 23, 2017 At 1.6Kg/cm the Futaba 3114s do look a bit wee. These would be better at 2.5kg/cm (at 4.8v) and I have bought quite a few of these to good effect in small models like this. My only other thought is that the dihedral of the three channel wing might prove to be a bit much with the ailerons fitted, aka they might not work that well. Reducing the dihedral a tad would be advised. Short of sawing through the wing, difficult to achieve, might be better building a new wing. Edited By Piers Bowlan on 23/10/2017 14:18:32 Quote Link to comment Share on other sites More sharing options...
Fylingdales Flyer Posted November 6, 2017 Author Share Posted November 6, 2017 Apologies for the delayed response and many thanks for the advice. Nigel, I've had no success getting the Sanwa servos to work with a Futaba receiver. The servos heated up quite alarmingly when connected and did not respond, so I think I will buy the ones suggested by Piers. Piers, thanks for the suggestion, I'll order some. The Mini Super was built from a Ben Buclkle kit, but is a tail dragger as was the original Boddington design. However, it does have the reduced dihedral of the Ben Buckle plan, about 3/4" under each wing tip, so I'm hoping it will be OK. The wing covering was damaged when something was dropped on it, so I thought I would convert to ailerons whilst re-covering it. Quote Link to comment Share on other sites More sharing options...
Geoff S Posted November 6, 2017 Share Posted November 6, 2017 Sanwa servos will operate OK on a Futaba receiver provided the connections have the positive battery connection to the centre. If they're old Sanwa servos with the connection lead with the 0v (or negative battery) connected to the centre pin you've burnt them out with a reverse polarity connection. If you have other Sanwa servos it's quite easy to move the connection to be the same as everybody else's ie signal/ batt +ve/ battery -ve. I would have thought 1.6kgcm servos would be OK if there's one/ aileron. It was common to use a single Futaba 148 servo for both ailerons and they're only about 3kgcm IIRC. 2 x 1.6kgcm should be fine. After all I don't think a vintage style model is going to need violent or large aileron movements. Geoff Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted November 7, 2017 Share Posted November 7, 2017 You are probably right Geoff, a 1.6kg/cm for each aileron would be enough, but with more powerful 12g servos of reasonable quality/low price available nowadays, I would tend to use the s3114s in indoor or park flyer models. More to the point, these tiny servos have very small plastic gears which are easily damaged. That is just me though. 3/4in dihedral under each wingtip sounds ideal. A bit of differential aileron can be a good idea too. Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted November 7, 2017 Share Posted November 7, 2017 I have used Turnigy 9 gram servos with metal gears on models with .52 four strokes without problems. The Mini Super will not apply huge loadings on them. Quote Link to comment Share on other sites More sharing options...
Jimbo565 Posted November 7, 2017 Share Posted November 7, 2017 BN This is my Mini,built many years ago,Built a new wing with flaps and ailerons with reduced dihedral and it flies a treat although it can be a handful on the deck. As you can see from the pic I made the ailerons too narrow and they did not have a lot of authority but the model still flew well. I have since re.built the wing with ailerons the same width as the flaps,should have better response as it has not been flown since the mod.I used Hitec HS 82 servos for flaps and ailerons. Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted November 7, 2017 Share Posted November 7, 2017 Another very tidy model from Jim . Hitec HS82MG, a good suggestion, if possibly overkill? ( I have used plenty of those!) Quote Link to comment Share on other sites More sharing options...
Jimbo565 Posted November 7, 2017 Share Posted November 7, 2017 Quote Link to comment Share on other sites More sharing options...
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