In order to allow easy removal of the stabs and an installation method similar to all my other Comp-ARF models, I chose to mount the elevator servos (JR3401) in the stabs themselves on their side. This involved cutting a square out of the underside stab skin (50mmx30mm) and building a little framework to clamp the servo in place. It was then simply a case of dropping the servo 'box' through the hole and expoying it to the upper wing skin in a position that allowed a nice straight linkage to the elevator horn. NB I removed the web on the mounting lugs so that I could get the servo lugs to be a a nice tight fit between the wooden posts that hold the servo in place. When everything is in place, the 50mm x 30mm skin is trimmed to allow room for the servo arm and simply held back in place with some clear tape. The photos below are fairly simple to follow.
I chose to fit stab adjusters too my model for a couple of reasons. Firstly, I didn't trust myself to get the incidences set perfectly accurately and secondly I like the idea of incidence adjustment on the stab as it allows the most flexibility in getting a perfectly dialled in model. I used the gator stab adjuster items but had to find where/how I could mount them! After a lot of head scratching I chose to fit them up against the stab tip side of the ply root rib. I made up a false ply rib to which I screwed the adjuster and simply glued it in place as far back into the stab as the adjuster's height would allow. This was to ensure the anti-rotation pin was applying the maximum anti rotation force as possible. I also tried to ensure that the centre line of the adjuster was as close to the centre line of the stab as possible. This would ensure I had the maximum amount of adjustment in either direction. Following this, I marked the points on the top and bottom of the stab for the small 2mm holes needed to alter the adjusters and drilled them - fortunately they lined up perfectly.
Having got the adjuster in place, I needed to mark the point of the hole in the fuselage for the metal anti rotation rod. I placed the rod into the adjuster and clamped it tightly so that approx 2mm of the bar protruded from the stab root. The tip of the metal anti-rotation pin was coated in black ink, the stab put on the fuse and held at as close to 0 degrees incidence as possible before pushing the stab up against the fuse so that the ink on the metal pin marked the fuselage where the hole needed to go. This process was repeated on the other side and the two holes drilled in the fuselage. The metal pin was installed in similar fashion to the stab tube i.e. with two ply donuts holding the pin in place inside the fuselage. Remember to roughen up the metal pin where there is to be glue contact.
N.B The photos below show the installation tack glued prior to the final application of Aeropoxy
Further photos to follow.
Mounting the aileron servos looked like it was going to be a nightmare but proved pretty easy! Before you do anything make sure you centre your servos remembering to check for any programming which may alter the true centre, then fit and secure the servo arm. (I use SWB double-loc servo arms). I also added an appropriate length extension lead, securing it with some heatshrink tubing as per the photo below. I now needed to get the servo in situ. I found a length of small chain that I fed down into the wing, into the hole behind the servo cut-out and then back through the servo cut-out and back out the wing. Next I taped the servo plug to the end of the chain that went through the round hole and pulled the lead through. A little bit of wiggling and prodding with a 60cm long 6mm carbon tube had the servo fall into the cut-out. Next came the screws which again were surprisingly easy. I simply taped a magnetic screwdriver bit to the end of my carbon tube and used it as a screwdriver and Voila, they were in! Due to the way in which the SWB arms sit on the servo (i.e. much nearer the case top) I needed to open the servo arm slot slightly and that was it - finished!
Next up was the fitting of the U/C mounts/formers/legs in the fuselage. The formers are very nicely cut from a carbon/ply/carbon sandwich. Firstly, the slots were cut in the fuselage for the for the U/C legs following the indentations marked on it during the manufacturing process. Next I fitted 4mm captive nuts to the u/c mounting plate and transferred the hole positions to the carbon u/c legs. I drilled 5mm holes in the u/c legs so that the slightly protruding captive nuts in the u/c mounting plate would not stop the legs from sitting flat on the mounting plate. The u/c formers were trial fitted in the fuselage, slightly sanded for a snug fit and then glued together using epoxy. Once cured, the formers were placed in the fuselage and epoxy used to secure them in place. The u/c legs were then bolted in place using 4mm bolts and washers.
Firstly, a 4mm hole was drilled in the carbon leg using the factory provided indentation. A 4mm hole was also drilled in both sides of the spats, again using the factory indentations as a guide. Next, the outer hole of the spat was opened up to a size that allowed the bolt head of the axle to just pass through it. A scrap piece of ply was glued inside the spat on the surface nearest the u/c leg approx 3mm above the axle hole.
The wheels were then mounted. The order on the axle was washer, wheel, washer, spacer, 4mm locknut, spat, carbon leg, washer, 4mm locknut. With everything nearly tightened it was time to set the angle of the spat remembering to either fit the tailwheel first or at least prop the rear of the fuse up accordingly. When I was happy with the angle I drilled through the carbon leg and spat and into the ply piece I had previously glued inside the spat. A small screw was then used to screw through the leg and into the ply thus securing the angle of the spat and stopping in from moving.
I chose to fit an MK tailwheel unit. A 1/8" ply plate was epoxied in the fuselage as shown to give me something substantial to screw into. The MK unit is a nice piece of kit and comes recommended!!
I chose to get the canopy mounting out of the way next. First of all I cut the 2mm wide slots for the phenolic 'hooks' and glued them in place with epoxy. Be sure to allow enough of a gap under the 'hook' for the thickness of the fuselage and the phenolic U shaped guides. Next I marked the slots on the fuselages to accept the 'hooks' in the canopy. These were carefully measured, marked and cut. Next up was the canopy latch. It was a simple case of cutting a slot to allow the latch pin to be pulled back and a hole for the latch pin to protrude from. The latch was held in place with a puddle of epoxy. The final part of securing the canopy was the front retainer. This used the same method as the cowling i.e. a 4mm bolt head through a hole and then the 4mm bolt shaft sliding along a 4mm wide slot. The pictures explain it better than I can! With everything in place there was a little bit of time tweaking the various parts/slots to ensure a rock solid fit.