The fuse is where the most work is to be done i.e. fitting the rudder servo tray, fitting the rudder pull-pull system, the undercarriage, tail wheel, the battery mounting system, motor mount, ESC mount, receiver mount, receiver pack mount, receiver regulator mount and last but not least, the CRS mount.
I tackled the rudder servo tray mounting first. The rudder servo tray is laser cut from 2mm light ply. A doubler is also supplied for the servo cut-out and this was glued in place with CA. I found the tray to be more flexible than I liked so balsa bracing was added to the sides and across the tray. See photos. This modification easily reduced the tray's flexibility by 400%! Once glued to the fuse sides it will be even more rigid. The rudder servo used is a Futaba BLS452. The servo was fitted to the tray and the mounting holes were marked and then drilled. Because of the nature of the rudder tray, a drill press was used.
The rudder tray was located directly under the rear edge of the canopy opening. See photos. You could mount the rudder servo further forward if wanted but that option may require a wider plate to be made. Had the factory fitted the tray this flexibility in mounting position would not be so easy. The rudder tray was glued in with 30 minute epoxy. Note: The balsa stiffening bracing I added earlier also increased the surface area to be glued to the fuse sides.
The Allure includes a pull-pull rudder kit. I elected to fit rudder horns purchased from Ralph Schweizer along with Dubro Ball ends at the servo and Dubro Precision clevices at the rudder. The factory supplied cable was used in conjunction with Sullivan Eye bolts. A Secraft 2.5" rudder servo arm was also used.
The rudder horn will need to be fitted to the rudder. First, locate the hard point in the rudder. I used some masking tape to mark out the hard point location. I then marked the middle of the hard point on both sides. The rudder horns come with a washer that the nut locates into. The washer has a cup and the nut has a rounded end. This allows for a neat fit on the tapered rudder. The edge of the washer was located on the bevel of the rudder leading edge and a marker was then used to pinpoint the hole centre. Now the tricky bit, drilling thSe hole for the rudder horn. Here's how I did it... I used a small drill to make the first holes from both sides of the rudder. If you were careful with your measurements and the angle which you drilled at, the holes will intersect. Then it's just a matter or slowly opening the hole out to 3mm to match the rudder horn.
You will need to cut the rudder pull-pull cable exits in the fin. I made a jig to do this. To make the jig, I traced out the path of the cables on the work bench. The span of the Secraft rudder servo horn is known and the rudder horns are the same width. We can also measure the distance between the servo and rudder horn. The rudder cables are crossed in the fuse. With all this information it was quite easy to draw up the whole pull pull system on the bench. Then I made a balsa jig that matched the lines drawn on the bench. The jig was made to straddle the rudder evenly and then the length of each finger was adjusted until it neatly fitted on the fin. This is the cable exit point.
The next task to be tackled was the Contra drive soft mount. Now on this model the nose had been pre-cut out by the factory to suit the contra. In future, the contra and electric Allure will be one and the same thing.
IMPORTANT NOTE: The canopy opening is the datum or zero reference for the Allure.
So, first thing to do is check that the factory has set the nose in the model correctly. The nose should have 0 degrees right thrust and -0.5 degrees down thrust. After setting the datum on the canopy opening, I found that only a minor adjustment was needed to get the down thrust bang on -0.5 degrees. The side thrust was checked with reference to the wing tube using a ruler. No problems were found here. Now that the nose was set up correctly, it could be used as a base for gluing in the RS soft mount firewall in place. The ply firewall required a little adjustment with the Dremel. The adjustment involved bevelling the outer edge to match in better with the fuse profile. Once the Dremel work was done, the CRS mount was dry fitted to the fuse along with the CRS and a 2.5mm hard balsa spacer. The spacer was used to keep the gap between the CRS spinner and fuselage constant. Once happy with the fit, 30 minute epoxy was used to glue the firewall into place. The CRS rear mount was fitted / constructed next. Ralph supplied a sheet of 1mm carbon to make the rear mount wings (for want of a better description). Templates were made using hard balsa and once happy with the fit, carbon duplicated were cut from the 1mm sheet. The carbon wings were then glued to the fuse sides with 30 minute epoxy. Note: The spinner spacer must remain in position until the rear mount is finished. This ensures the thrust angle is maintained.
A tail wheel assembly is included in the kit. The actual tail wheel itself is not included. As I didn't have a tail wheel laying around in the shed, I decided to fit an MK Tail Wheel assembly. Fitting the tail wheel is pretty much self explanatory, the only thing I did a little different to normal is place a small piece of silicone fuel tube between the bottom of the rudder and the tail wheel arm to prevent chaffing.
The undercarriage legs will require drilling for their mounting screws and for the axles. The factory U/C plate comes with blind nuts for two M3 screws on each leg. Edit: The U/C plate now comes with three blind nuts for each leg. I highly recommend fitting an additional screw to each leg. Tip: Use a small piece of paper cut to match the U/C leg profile to transfer the U/C plate mounting holes to the U/C leg. Simply place the paper on the plate and then use a pencil to poke holes into the paper wher the blind nuts are. Then transfer these punched holes to the associated U/C leg, centre pop and then drill. I used a drill press for this purpose. The U/C mounting plate was reinforced with some epoxy/glass filings underneath and four carbon tows on top. Photos below including a picture of what the factory is now doing to the gear plate. The factory had used epoxy/micro balloons in this area which I think is inadequate for the purpose so it was removed prior to laying the carbon tows. I recommend reinforcing this area to prevent failure in a hard landing. Yes, we all have a bad landing every now and then... I used TY1 65mm wheels. These wheels are very light and are also narrow. This narrow style wheel helps improve the longevity of your wheel pants.
I use a slightly different method to most for mounting the wheels and pants to the U/C legs. It makes for a strong and durable wheel pant install. The wheel pants supplied in the kit are nice and light and made out of fibreglass. To improve rigidity, I added two pieces of 3oz carbon cloth to the inside of both pants. The U/C leg needs to be drilled to suit the kit supplied Aluminium axles. Start off with a 3mm drill bit and then counterbore the side that interfaces with the pant to suit the axle. 10mm above the axle hole centre, dill another to suit a 4-40 Screw. This will be used to hold the pant on later. Next I made some blind nut plates using 2.5mm ply cut to 10mm x 20mm dimensions. Make two of these small plates. Then draw two diagonal lines corner to corner. This marks the centre. Make a centre pop and drill to suit a 4-40 blind nut. Then insert the blind nut and push home in a vice. Add a drop of thin CA to secure. You may need to grind down the blind nut so it sits flush with the ply plate. The Dremel makes short work of this task. Next, we make the axle end supports. I made theses out of 6mm ply cut to 10mm x 15mm dimensions. Make two of these support plates.Then draw two diagonal lines corner to corner. Again, this marks the centre. Drill a 4mm hole in the support plate to suit the axle. By now the carbon cloth epoxied to the inside of the wheel pants should be cured. This assumes you work as fast as me i.e. slowly... If it's not cured you work too fast! Firstly, make sure the wheel opening is large enough for your wheels and is positioned the same on both pants. Adjust using the Dremel as required. Now we need to ensure you have a left and right wheel pant. Place some masking tape on the side that will interface withe the U/C leg. The tape wants to be on the centre of the wheel opening. Now measure the half distance of the wheel opening and mark it on the masking tape. Place the pant on a flat surface and extend the mark vertically. This will be the axle centreline. Make a second mark 10mm up this line from the bottom of the wheel pant. Centre pop this mark and then make an 8mm hole. I normally use a suitable grinfpding stone in the Dremel for. this as it makes a nice neat hole. We can now dry fit the axles, wheels and pants to the U/C legs. Now sit the model on the bench as it would sit on the ground at the field. We'll now set the angle of each wheel pant. To set the angle of the pants I place a 10mm spacer under the back edge of the pant. Then, with a suitable marker or a drill bit, mark the hole above the axle onto the wheel pant. Repeat for the other pant. This marks the position of the fixing hole on the pants. Centre pop these marks and drill a 4-40 hole. Yep, it's a long winded process but the results are worth it....
Now we get to use some glue. The ply plates with blind nuts need to be glued to the inside of the wheel pant. Rough up the inside with some sand paper and the glue the plates on with 30 minute epoxy. I assemble the pant to the leg with the 4-40 screw to hold it all aligned and clamped while the epoxy cures.
The 6mm ply end supports we made earlier will need a little shaping to match the wheel pant profile. The Dremel makes short work of this task. Once shaped correctly, it will comfortably fit on the axle and up against the inside of the pant. Again, rough up the inside of the pant with sand paper and then glue it to the pant with 30 minute epoxy. Assemble the pant completely to glue the outer support. You may also use some small clamps to hold it against the pant side.
Once all epoxy is cured, you can then assemble the whole pant with your wheels and collars. You'll probably need a plastic 4mm spacer to position the wheel centrally in the pant opening.
The kit is supplied with a battery tray assembly. I elected not to use this in preference over making my own tray that also holds the ESC and Safety Power Switch (SPS). This makes the whole thing modular. The carbon tubes that come with the factory battery tray were used along with some 6mm ply blocks glued to the fuse sides.
Cooling holes were cut in the underside of the nose and some exit holes were cut under the rudder tray. I believe that future kits will have these particular holes already cut for you.
We now have a light-weight accessory kit in the shop. This replaces most of the factory supplied hardware with items made from Titanium and Aluminium.