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Construction (Page 2)


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Tail Feathers:
The construction of the tail went off with very few problems. The stab lined up fairly well to the wings. Only minor adjustments were required.
My first step was to glue in the tail wheel plate. The plate supplied is a piece of 1/4" aircraft ply that is glued in to support the tail wheel. The first thing I did was lighten up the plate a bit, by drilling in a few holes in key areas where I felt it was safe to do so.  Once the tail wheel plate was glued in, I then took a few measurements on the stab, and how it lined up to the wings.
Like the wings, I now had to calculate the wing incident of the stabs. Again, I set the whole fuse to 0 degrees, and used an incident meter to set the stabs to 0 as well. Once everything was lined up, I then drilled a hole in the fuse, and glued in anti rotation donuts, exactly in the same manner of the main wings. The only difference is that instead of using two donuts per side, I used only one donut per side. (The stab only needs one)
The next step was to glue in a support former to stiffen up the whole tail section. This former was supplied in the kit. It's a piece of 1/4" balsa that when installed will sit at 45 degrees to the tail post. Again, and like the tail plate, I decided to lighten it a little more.
        Once the support former was dry, the next step was to glue in the tail post. The tail post supplied is a piece of 3/4" balsa. After looking at the tail post and rudder, I decided that I wanted to double bevel the rudder, for 3D type control throws. In order to achieve this, I only set the rudder post in by 1/2" thus leaving a 1/4" to protrude, giving me some wood to bevel back. I used clamps and an old hockey stick as braces while the glue set.
Once the glue was dry, I had another look at my rudder, and decided that I wanted a larger counter balance. In order to achieve this, I had two options. Either add a piece of balsa on top of the rudder, or cut the fin and add a piece of balsa under the counter balance. I decided to cut the fin. I don't want to make the fin any larger then it already is, I just want more counter balance. So what I did was cut about 2 inches off the top of the fin, then glue in a piece of 1/8" light ply to reinforce the cut. Once that was done, I temporarily tacked on a piece of balsa to the top of the fin (see photo) I then sanded it to the shape of the fin. Once the shape was achieved, I then glued the rudder to it, broke off the temporary glue joints, and had my larger counter balance.
Once all that was done, all that was left is to hinge, and create my double bevels as in this photo.

Fuse formers and Canopy:
When building models we all make mistakes, or perform a step and say after the fact "shoot, I wish I could do that over!" Well I'm no exception, and if I could do my canopy installation again, I would think over the process a bit better. (laughs)
Zn line supplies you with a nicely tinted canopy and a fitted canopy frame, that fits very nicely into the canopy opening of the fuse. The idea here is to fit the canopy frame to the fuse, then glue on the canopy, making set up easy. right? That is if you follow those steps. Unfortunately, while I was waiting for my tail post to dry, I figured why not fit and glue the canopy onto the frame. The problem is that now it makes fitting the frame to the fuse a lot more complex especially with the canopy already attached to the frame.
Since the canopy is already attached to the frame, I had to get a little creative in getting it to fit. After looking at the opening, I figured that 2 dowels in the front of the canopy, and 2 hold downs towards the rear were how I was going to hold it in. My first step was to drill two holes into the fuse at the forward canopy opening. These holes are to accept the 2 dowel pins that are going to be glued into the front of the canopy frame. I made the holes a little oversized so that I can adjust the fit of the canopy. Once the holes were drilled, I then glued in two 1/4" dowel pins into the forward part of the canopy, making sure that the pins were angled to fit parallel to the opening on the fuse. I then fit the frame onto the canopy opening, adjusting it to fit. Once it fit nicely, I then glued in 2 donuts, similar to the way I aligned the wings and stabs. I had to get to them from the firewall opening of the fuse (good thing I haven't mounted the motor in yet!)
Now that the front end of the canopy is mounted, the trick is to mount in the hold downs at the rear end of the canopy.
My first step was to glue in half inch dowels inside the fuse as shown in the picture. The reason for these dowels is to support the screws that will be used to hold down the canopy. Now the trick here was to get the hold down tabs to line up with the canopy. So I drilled and installed the tabs, blind nuts, and screws before attaching in to the frame. I used a little 90 degree angles I made out of some scrap wood to get the tabs to align. Once everything was dry and aligned, my next step was to attach the tabs to the frame.
        I then cut little slits into the bottom of the canopy frame to accept the tabs, thus allowing the tabs to protrude from inside the canopy. Once I got that to line up, the final step was to glue the tabs to the frame. Again, this was a little tricky, and I had to use an epoxy brush, taped to a long stick, and from the opening in the front of the fuse, I very carefully applied the glue, allowing the tabs and frame to set up in the right position. Once everything was dry, I took the canopy off, sanded the glue joints a bit, and re-applied a bit more glue to make sure it was attached properly.
I did get a good fit, but all of this could have been avoided if I would have not glued the canopy on to the frame. Lesson learnt for next time.
Now that the canopy was attached, I decided to finish off the remaining fuse formers.
The kit comes with the formers shown in these pictures, and I installed them as they were meant to be installed. The only difference is that I decided to drill them out to save a little weight. Other then that, there wasn't too much deviation here. The whole concept here is to create a frame inside the fuse. The one former in the rear turtle deck, is attached to side rails, which are attached to the main wing tube. I think that this is an adequate set up, and needs little more.

Main and Tail wheels
The main and tail wheels, are both pretty straight forward. I used a Graupner carbon fiber tail wheel, that is very light and strong.
The mains were set up fairly straight forward as well, with one slight twist for all you weight conscience modelers out there. This is a trick that was shown to me from a local modeler here in Toronto.
I took a standard 1/4" Dubro axle, and with a hammer/center punch knocked out the main axle, thus only leaving the threaded skirt. Once I removed the axle, I then made an axle from 6 mm carbon fiber rod. (The rod was slightly smaller, but I used a little tape and glue to get it to fit nicely) The end result was a savings of about 3/4 of an ounce per axle. Not bad!

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Last Updated 05/03/2007