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  • #16
    For stab linkage, used a Z-bend at the servo and an L-bend at the surface, made long enough such that it cannot become disengaged with the stab mounted. The arrangement is rock-solid with no slop whatsoever.
    Last edited by tewatson; 01-08-2019, 01:23 AM.
    Tom

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    • #17
      Looking good, Tom!

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      • #18
        Simple and extremely reliable setup Tom, Thanks for posting the pictures, I know Rick was explaining the setup but his photos didn't show on the forum...
        Len Buffinton
        Team Horizon Hobby

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        • #19
          Tip on installing/removing the stab with this arrangement: Before disassembling, input full "up" and then power off the plane. The rearward position of the surface horn and link makes it easier to access.
          Tom

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          • #20
            Nice work! Scale Models just keep getting better and better. We are so lucky in this hobby. Having the wing servos preinstalled was a good idea. I don't enjoy wing servo installation on a 10 servo wing...

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            • #21
              The rudder servo bracket, pushrod and control surface horn are factory-installed. It was just a matter of mounting the servo and connecting the pushrod ends. Kept things simple with a clevis at the rudder and a Z-bend at the servo.
              Tom

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              • #22
                Landing gear setup was next. The retract assembly is a work of art. It looks to be superbly engineered with a drum brake, integral servo mounts and carbon fender. The retract servo is factory-installed with linkage fully adjusted. The gear door spring arrangement is left to the builder.

                Completing the retract assembly setup just required mounting a brake servo and connecting the cable. I used a 4-40 clevis and rigging coupler for adjustability, with the cable secured by dual crimp ferrules and a dab of JB Weld to ensure nothing slips.
                Tom

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                • yyz
                  yyz commented
                  Editing a comment
                  The quality of that retract looks amazing. Are there shocks?

                • tewatson
                  tewatson commented
                  Editing a comment
                  No actual shocks, but the aft end of the unit is bolted to rubber bushings that have some give.

              • #23
                Landing gear door springs required a bit of thought, as there was no room at the forward end of the retract assembly, and limited room at the rear. Tried mocking up a torsion spring, but the full-length hinge setup resulted in too much physical spring displacement for that to work. My pal Dennis Brandt suggested coil springs with an overhead support rod, so did a test setup and it worked perfectly.

                Used a small-diameter carbon tube with ply support blocks on both sides (one side is captured, other side is slotted to allow removal), soft long-throw springs for light but even tension, and #1 dress hooks on the doors. Very simple and functional. The final assembly will include a larger tube over the support rod, in between the springs, to maintain proper spacing.
                Tom

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                • #24
                  Moving forward to the nose area, poached an idea from Steve Condon's JS-1 and fabricated a tray arrangement that mounts the tow release servo and batteries, while also providing a compartment for nose weight. Aircraft ply bulkheads hold a removable ply shelf with a dado slot at the forward end, and socket screws at the aft end.
                  Tom

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                  • #25
                    With the major fuse arrangements solved, it's time to finalize and secure the wiring. Using the PowerBox Champion SRS unit for battery and RX management, with dual (redundant) JR DMSS RXs. The unit accommodates serial bus communications with multiple radio brands, so it does not lock you into using just one manufacturer's equipment. This is a huge advantage for future flexibility. More on this unit later when the cockpit area is finished out.

                    The retract is reinstalled and all wiring harnesses are routed and connected. Everything is secure, and arranged such that maintenance will be easier. RX and battery placement is next up.
                    Tom

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                    • Mark Taylor
                      Mark Taylor commented
                      Editing a comment
                      Really nice!

                    • tewatson
                      tewatson commented
                      Editing a comment
                      Thanks Mark.

                  • #26
                    Using dual redundant JR 812BX DMSS serial bus RXs, with additional diversity satellites, for a total of eight antennas. Protective sleeves (un-shrinked shrink tubing) are used where other wires could touch the exposed coax ends. These pics also show the power/programming switch for the PowerBox unit mounted to the battery tray. It is bulkier than standard switches, but another feature I like is it cannot be inadvertently switched on/off; it requires pushing two buttons simultaneously to operate.
                    Tom

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                    • #27
                      Batteries are lithium-ion, using four 3,500 MAh cells each, in a 2S2P configuration for 7,000 MAh per pack. Leads are 14 gauge.
                      Tom

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