Posts: 1003
Joined: 5/24/2003 From: Atlanta, GA, USA Status: offline
Jeez Greg....who sponsers all these conversions and where do I sign up I have looked at this one too for conversion. It should be pretty simple. Good luck.
HTS085MG Hitec HS-85 "Mighty Micro" Metal Gear Servos (4)
RCD120 Hitec "Electron" 6 Ch. Micro FM Receiver
HT0096 Aileron "Y" Connector and two HLAE322 24" Extensions
PM41001 Aluminum Motor Mount for AXI 41 Series Brushless Motors
MJ4706 Collet Prop Adapter for 6mm Shaft, M8
KFS001 Ultimate BEC
DEA1300 Deans Ultra Plug connectors, pair
I will be experimenting with various APC prop sizes from 13x8 to 15x8. At this time, I am not 100% sure which AXI motor mount will work best on the Skylark so I have both to try. It is possible that the PM41001 mount may not fit in the fiberglass cowl. I'll report on that later.
Posts: 4310
Joined: 5/24/2003 From: Rochester,
NY, USA Status: offline
The assembly starts by gluing in the pre-installed aileron hinges. There are 4 hinges per aileron.
I roughed up the nylon and metal pin hinges with sandpaper and then glued them in place using Aileene's Tacky white glue. First, I coat the inside of the slots in the aileron and then the wing. Next, I coat the hinge itself and insert it into the wing. Once all 4 hinges are installed, I attached the aileron and press it on as far as it will go.
The wing halves are then glued together with a rather thick balsa spar that runs between custom openings on each wing half. You need to orient the spar properly as it has a front and top side.
The spar and wing halves fit together perfectly without and sanding! I used 5-minute epoxy to first glue the spar correctly into one wing half, and, after it dried, I glued the two wing halves together making sure that every surface was covered with a coat of epoxy.
I decided to pay close attention to make a perfectly strong wing joint because I would skip the fiberglass reinforcement step that followed. After studying the wing frame and mounting scheme to the fuselage, I decided that I had plenty of strength for my electric conversion.
Posts: 4310
Joined: 5/24/2003 From: Rochester,
NY, USA Status: offline
Before gluing the wing halves together, I decided that it would be easier to run my aileron extension lines first since there were openings in the center end of each wing to aid in the cable run. The wings and fuselage come with strings inside to guide in routing the servo cables so skipping these steps as I did is not necessary.
My Skylark wing assembled perfectly aligned and strong. There is 54mm of dihedral built into the wing frame to aid in flight stability.
Here you can see solid fuselage design, pre-drilled firewall, and attention to details like access compartments and string guides to pull servo leads and antenna wire.
Posts: 4310
Joined: 5/24/2003 From: Rochester,
NY, USA Status: offline
The Skylark wing mounting scheme is precise and solid. The plastic fasteners are screwed into place on the fuselage into custom channels. The wing leading edge uses a hardwood spar from each half that was glued together. The trailing edge is then reinforced with additional hardwood plates which is also used to mount the saddle.
The result is a seamless joint between the wing and fuselage that is locked in place with perfect incidence.
Posts: 4310
Joined: 5/24/2003 From: Rochester,
NY, USA Status: offline
To mount my AXI 4120 motor on the Skylark, I initially tried using the PM41001 Aluminum Motor Mount but found that the frame did not fit in the custom fiberglass cowl. I then tried the PM41002 Radial Mount Set, and, although it did fit in the cowl, the length was too short.
The length problem was easily solved by using a common piece of PVC available at any home improvement store or hardware store. The 2" coupler (Schedule 40) was a perfect fit. I used 10-32 hardware with 3" long screws and Tee nuts to secure the assembly. I'm sure that #6 or #8 hardware would also work but I didn't find the 3" length screws at Home Depot.
A small ridge runs along the inside of the coupler center that needs to be filed flat where each screw passes. It is a simple job with either a round file or Dremel tool sander.
The motor mounted easily and is rock solid. I used a little Locktite inside the Tee nut threads to help keep it secure. Note that both down thrust and right thrust are built into the firewall.
Posts: 4310
Joined: 5/24/2003 From: Rochester,
NY, USA Status: offline
The Skylark landing gear mains are mounted into pre-cut channels in the wing bottom. The pre-bend spring rod presses into the channel with one end going straight into a hole. The assembly is held firm with a few straps screwed into the wood frame. No glue was used.