Monday, August 26, 2013

Needle 115 assembly

Nothing special to say about the assembly of my Needle. In the fuselage the work consist in installing the servos tray. I made a longer one in order to go almost up to the wing root as reinforcement. The tray is glued first with epoxy, with some carbone in the corners. Then I applied 2 layers of 110g.m2 fiberglass going on the side of the fuselage to make the traya nd the fuselage as one piece. I do this on all my F3F ships and I'm very satisfied with the robustness it gives. The Elevator servo is a MKS DS 6125-H a,d the rudder one is a MKS DS 6125-e. I used a tiny RG611B  receiver, DMSS modulation, 6 channels. The battery is an hyperion LiFe 2100 mAh which fits very well in the nose. The Zepsus magnetic switch is connected between the battery and the receiver. This means I'm in HV, no voltage regulator in front of the receiver. For this reason, I installed 2 S-BEC in front of the rudder and elevator servos.

I didn't follow the standard servos installation in the wing, using epoxy horns and fixed metal rod, bended at the exact size, like on my Needle 100. For the N115, I wanted to reused the system I have on my 2 Pikes Precision and that give me entire satisfaction as after 2 seasons of intensive use, I have still no slop at all on the servos !
The system consists in using the RDH and Fu-Fix external ball bearing, mounted on MKS DS 6125 Mini on the ailerons (with a 1.5A S-BEC in front) and MKS DS 6125 glider on the flaps (with a 2A S-BEC in front) . This requires more attention during the installation, but the result is absolutely slop free. On the ailerons/flaps side, I now used MPjet brass horns as I have been disapointed by the MPX metal horns which can bend, then break during hard landings. The M2 MPX clevis is perfect to use with the MPjet brass horn. Of course at the end you see the clevise exiting on the upper skin, but I prefer a good servo and slop free installation than a invisible one that gives flutter, and some maintenance at the end.

With the preproduction fuselage, I needed lots of lead in the nose to obtain the recommended CoG at 89 mm. The N115 weights 2371gr. With the production fuselage, I think it is possible to end around 2200gr which is ideal for F3F.

For the maiden flight, I programmed the settings quickly, knowing that I will need ajustement. Let's go the slope !!!


  1. Hi Pierre!

    I am just working on my needle 115, trying to install 2xMKS 3125miniH Servo for elev and rudder. But obviously the height of these servos is at or beyond the limit set by the small nose. How did you arrange to use those 29mm (height) servos? Might it be the case your needle has a thicker nose design as you got one of the first planes (prototype?).


    1. Hello Michael,
      I have the standard fuselage, and the mini-H can be installed. Of course it is not easy, but possible. the servo tray must be installed at the right height, this is maybe the problem you have. Don't hesitate to modify it a bit if needed. On my new needle I succeeded to install a bigger servo, the MKS HV 737.