The same Leaf Blowerairframe (above left), but with the EDF unit removed. The fuselage has been modified for a motor/prop installation (above right), the
¼-inch balsa is used for the two booms, and the bottom of the fuselage and the bottom of the booms are level and parallel to the wing center line, the motor thrust line, and the stabilizer, for easy alignment of the whole assembly on a flat building surface. Any low temperature iron-on plastic film covering will work on the foam wing. I like the SLC material sold by The Core House. It’s light and accepts about any kind of paint. Of course you don’t have to paint this airframe, and could trim it up a bit with some light colored plastic packaging tape. Hinging the ailerons and elevator is done in the usual sheet foamy manner with 2- inch wide clear plastic packaging tape. The leading edges of the ailerons and the eleva- tor are cut and sanded at an angle, and the tape applied to the upper surfaces first. Then, with the control surfaces folded up- ward, the tape is applied to the bottom side, pushing it into the hinge gap and sealing it to both surfaces.
This provides free movement and a com- pletely sealed hinge gap. I didn’t bother with rudder control to keep things simple, but you could use two servos with straight pushrods to the two rudders if you think it’s worth the effort.
wing tips and tail surfaces modified, all for a sort-of-scale deHavilland Vampire/Venom/VixenBritish warbird look.
The servos are mounted by cutting holes in the foam so the servo is a push fit, and it is secured in place with a few dabs from a hot glue gun. Or, epoxy some 1⁄8-inch ply- wood mounting pads into the foam and mount the servos with the usual screws.
Slots are cut in the control surfaces and the 1⁄16-inch plywood control horns epoxied in place. I use .047-inch wire for the pushrods, with a Z-bend on one end and DuBro’s mini- EZ link on the other end. Hot glue short pieces of plastic tubing to the boom to keep the elevator pushrod from flexing. The ESC, receiver, and Li-Po battery are mounted to the fuselage with hook and loop material, and I cut slots in the fuselage for a hook and loop strap to secure the battery pack in place. The ELE 70mm EDF unit comes with the brushless outrunner motor installed with an 8-bladed fan, and it re- quires a 40-amp ESC. I used a 3-cell 2200 mAh Li-Po battery pack and lightweight Co- rona servos, all available from BP Hobbies. The EDF unit is held in place with a few dabs from a hot glue gun.
If I paint a foamy model, I use water based acrylic craft paints—easy to use, available in lots of colors at arts and crafts stores, and they’re low cost. A low cost, simple airbrush
works fine and with a fairly large nozzle on the airbrush, thinning the paint with water works fine. A Sharpie marker pen can be used to draw a few panel lines on the air- frame for some detailing if wanted. This plane flies easily out of an underhand hand launch, and on short, dry grass, it slides easily across the ground and jumps into the air. It’s fun to see those ground takeoffs! Now to explain some of the other photo-
graphs you see with this article. After I had a lot of fun with my Leaf Blower, I removed the EDF unit from it for use on another jet warbird model. My friend, Lou McGuire, took the airframe, reshaped the fuselage adding some material to it, rounded off the fin/rudder shape, rounded off the wing tips and stab tips for an overall sort of British de- Havilland Vampire/Venom/Vixen warbird look, and put a motor with prop in the nose for power.
A system of about 150 watts provides good performance. We like to use the BP Hobbies 2212-13 motor, BP’s 18-amp ESC, an 1800 to 2200 mAh 3-cell Li-Po battery pack, and a 9–5 prop. It flies fine! Painted up as a war- bird with military insignia, it’s another way to go if you like the warbird look. Hey this stuff is fun!
Both version of the Leaf Blower, the EDF (above left) and the prop version (above right), feature proportions typical for a sport/aerobatic model. Twin
FLYING MODELS
boom design and swept wings help the jet fighter look. The bottom of the airplane is clean and smooth, takeoffs are easy on a dry, short grass field.
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