 |
Ok, on with the build. Trace the formers on to A4 paper and stick them using a glue stick to the ply. Some are big so stick some formers inside others. I did try a home photocopier but it shrank the formers a bit, then tried scanning and printing and that made it worse hence reliable pen and paper.
Took my sheet of ply, covered with stuck down formers, round to my friends as he has a Screwfix scroll saw. 2 1/2 hours later all the formers are cut out and a few other ply bits.
|
|
 |
To avoid building a banana fuz one makes a jig. Here is the start of the fuz jig with the vertical wood where the formers will go.
In case you are wondering how it works. The fuz is basically longerons and diagonal bracing and rather flimsy. On the plan one draws a long staright line a bit under the fuz, parallel to the datum line. Then at each of the formers one measures the height to the bottom of the former on the plan. Then these measuremments are transferred to the jig, so effectivley the fuz formers rest on these bits of wood. I need to add a piece of 1/4 x 1/4 (6mmx6mm) wood at the top of the jig each side. Across this will go wood to support the formers while I build
|
|
 |
When the Jig was fInsihsed I clamped in the formers to the horizontal bars so it is all square, then added the rear keel piece and some strengthening at the back and the rear longeron at the tail. |
|
 |
I then added the lower front lonegerons. These were glued with white glue and clamped up with clamps and camping straps. Plans called for 3/16 sq longerons, I used 1/4" sq, simply because I have one of those Permagrit 1/4 sq tools. It cuts the holes nicely for a nice tight fit |
|
 |
Once this has all dried then I can remove the horizontal support bars and add the top longerons. Oh and loads of other bits as well
|
|
 |
Fuz is taking shape nicely now. Got to the stage when I need to consider putting the battery, tow release and rudder elevator and tow release servos up front and the wing roots in the middle and the tailplane and rudder mounts at the back. |
|
 |
I made the elevator which was left overnight to dry with pegs holding it together. I now need to round off the LE and cut slots for hinges as the hinge line is just infront of the rear of the LE. Also I have to add 1/64 ply gussets to secure ribs to LE of elevator
A tip for these large elevators and tailplanes. Drilling the holes for the rear of the tailplane and the LE of the elevator together makes lining up a lot easier.
Parts of the TP and fin were now left to dry overnight
|
|
 |
I finished off the TE Spar of the tailplane with 1/32 ply with 3/32 sq spruce top and bottom on the rear face. On the front face is a bit more 1/32 ply. Ohh and lightning holes. To be honest I am not sure it was worth the effort as the whole thing weighed a little over 1oz and only very slightly less once I removed the holes.
Picture shows the ply doubler, bellow it is the rear side. The spruce is just about visable, |
|
 |
A fin has now been made. The wood at top is some pine to take the screw of the pintel. At the rear is 3/32 sq spruce to attach the 1/64 sheeting to give a shroud at the rear.
There is ply 1/64 sheeting and a balsa leading edge to be added as well as a bottom as well. This will be done when the rear of the fuz is done so as to get a neat fit. The tongue fits into the fuz and will be secured by a pin through the fuz and the tongue. On the rear of the fin will be a brass tube, a bit like a wing joiner except there will be a tube in the fuz as well, so the fin is removeable.
|
|
 |
Here is the rudder, the leading edge is 1/8 balsa, trailing edge is 1/32 ply with 1/8 balsa sanded down to give a nice sharp TE. The ribs are all 1/16 balsa (apart from bottom one), with 1/64 ply gussetts. The bottom rib is 1/8 balsa and the bottom is balsa tapered from LE to TE.
The horn needs to be added and the the brass tubes on the front of the LE for the pintels, then the LE added and rounded off. finally a bit of 1/64 ply at the bottom of the rudder.
|
|
