Leaving the soldering iron and landing gear alone for a while, let’s switch gears a little and break out the ZAP glue and build some wood parts again. The build of any model airplane is based on certain tasks that need to be done in order for other tasks to take place. With the Sopwith Camel, I need to properly space the fuselage top/aft turtle deck formers properly between the cockpit area and the horizontal stabilizer. To do this, the tail feathers have to be built up. Let’s get to it.
As you may remember, I designed the Camel with my CAD program, (Ashlar Graphite9). I printed out PDFs of all the drawings and went to the local print shop and printed them all out full size to build with. Also, since the CAD program is very accurate, I used the files and had all the wood parts laser-cut to speed up construction. So the first step for building the tail feathers is to lay out the plans and cover them with Great Planes clear plastic “Plans Protector” material.
Here’s the vertical Fin and Rudder details cut from the side view plans sheet.
Here are the Laser-cut parts used for the curved outline of the surfaces. Notice they are laid out so the balsa grain runs lengthwise with the individual parts. Once glued together, this makes the outline very stiff and resistant to warping.
Here you get the idea how they will go together, just like a kit build. These parts are 3/8 inch thick and the wood comes from Trillium Balsa, (www.trilliumbalsa.com) and the quality of the cuts and of the wood is first rate.
Here’s the vertical tail surfaces have been assembled and pinned to the building board. Of course the straight stick stock parts (also from Trillium Balsa,) are not laser-cut. I use TiteBond wood glue for most of my structural glue joints as I am not in a hurry for them to dry. It takes about an hour or so for them to setup. While this parts dries, I went on to build the horizontal stabilizer and elevators.
The horizontal surfaces are built mostly from straight balsa stick stock with only four laser cut parts making up the tips. Here you see the leading edge pinned in place with the 1/8×3/8 inch plywood reinforcement strip glued into place. I use ZAP medium CA to glue the plywood to the balsa parts.
Here you see a similar plywood center strip is glued in place reinforcing the trailing edge.
Between the two plywood center strips is the 1/8-inch plywood base plate. This reinforces the attachment points to the fuselage. Four 4-40 cap-head screws and blindnuts will be used to hold the horizontal stabilizer in place.
I filled in the area above the plywood base plate with 1/4-inch balsa sheet. I used TiteBond for this.
Here the center balsa filler pieces are glued into place. Later I will drill the four attachment holes through the balsa and plywood layers for the screws. Then with a sharpened brass tube, I will cut 1/4-inch diameter holes in the balsa centered on the smaller holes. This will allow the screw heads to set flush with the top of the horizontal stabilizer for a cleaner appearance.
Here one of the laser-cut tip pieces has been glued into place between the LE and TE strips. The tips are 1/4-inch thick so 1/16 inch shims are needed to center them between the LE and TE.
Here’s one of the elevator tip pieces along with a 1/4×3/8 inch ribs in place. The trailing edge is rough cut to length and will be sanded to shape later.
So here’s the completed tail surfaces ready to remove from the building board. Five minutes on the belt sander will finish the job by rounding all the corners and smoothing any bumpy glue joints.
Next we’ll install the horizontal stabilizer and begin on the fuselage turtle deck formers. Click here: http://www.modelairplanenews.com/blog/2014/06/30/workshop-build-along-sopwith-camel-part-8-tail-surface-attachment/
To see the previous installment, click here: http://www.modelairplanenews.com/blog/2014/06/23/workshop-build-alone-sopwith-camel-soldering-landing-gear/