ENGINE NACELLES

I started by constructing the plywood boxes which the engine, retracts and tanks all mount onto. Take care to make these with the correct offset for the inboard and outboard mountings. Next, I built up the balsa sides and then mount the complete nacelle on the wing, making sure of the correct down and right thrust. The retracts I used were Robarts mounted on the rails as shown on the plan but the legs were turned at 45 degrees as the undercarriage folds rearward inside the engine nacelles. Take your time with the retracts and they will give reliable service.

I decided to use separate servos for the throttles and mounted them in the nacelle under the retract. I used Hobby Electronics micro servos coupled with Dubro servo savers. Take time to adjust these for the transition of the throttles from idle to full throttle, especially keeping the engine revs the same at low throttle. Nylon radial mounts worked well with the engines side mounted and I fitted 180ml tanks in the space provided. The cowls are made from balsa block as shown on plan, carved, shaped, and mounted with three screws. Finish off the nacelles and then epoxy the entire inside to seal for fuel leakage.

FUSELAGE

The fuselage on this model is relatively simple to construct as there are no complications of engines or tanks. I began construction with sheet balsa sides, added the stringers then the formers F3 - F9. After the sides were aligned correctly, I added the top stringers and the turtledecking. The easiest way I have found to curve sheet balsa is to first use a squirt bottle to soften the wood by spraying it with water and ammonia (50% mixture).

After this, glue the wood to the airframe using thin cyno. Fit the wing next and drill the holes for the front wing dowels through the former F3 with the wing in place. This makes the job easier and more accurate. Then add the wing bolts.

Next the wing fairings are added and then shaped to suit. The canopy frames can now be added as well as the bottom sheeting. The nose is built simply in balsa and is a good area to add ballast because of the space available forward of the centre of gravity.