Close up of the motor and prop installation (at left). Some careful surgery would be needed to install a brushless motor in a pre-built model. The EasyStar Lite (above), finished with modifications and ready to go.
seems to give 50 to 100% better performance; not a rocket ship, but significantly better rates of climb than with the original motor. I mounted the new motor on a 1⁄16-inch ply- wood ring of 13⁄8-inch outer diameter, with the large inner hole allowing cooling air to the motor, and then CA’ed the disk (with
motor assembly attached) into a slot about 1⁄16 inch deep cut into the inside wall of the motor nacelle, positioned to put the prop just outside the nacelle. Care is needed not to CA the motor. Note that the result does not really provide for an easily removable motor; the 4–40 bolts simply hold the assem- bly together.
The motor leads must be extended to reach the nose cavity where the battery, Rx and ESC reside. Although I was originally tempted to place the 12A ESC just up be- hind the motor, I gather that is not good for noise pickup. It’s better to keep the ESC/battery wires short and lengthen the three motor leads. The new motor and
mounting disk saved 29 grams over the old brushed motor. I found very little weight to be saved easily in the fuselage and tail assembly without be- coming fanatical. I did install a couple of cooling holes into the bottom front of the bat- tery compartment, with an exhaust channel carved out at the rear of the removable canopy, since Multiplex doesn’t provide any. For the record, I used HXT900 9g servos (1.6kg-cm) from Hobby King, which are a bit smaller than the kit’s holes, so a little balsa wedging was required. I wrapped them with masking tape and CA’ed them in place. I chose a 3S Turnigy 1000 mAh battery
which is quite light at 87 grams, and is more than adequate for several climbs to altitude and overall flight times of more than 30 min- utes. This light battery results in the c.g. be- ing about 1⁄2 inch behind the kit’s recommen- dations, but, other than a bit of down trim required, it has caused no apparent changes to the flight performance.
So all told, I directly saved about 56 grams, chose light components for servos and battery, left off extraneous decals (sor- ry Multiplex!) and have ended up with a unique EasyStar with an all-up flying weight of about 470 grams. Since that’s al- most 100W/pound, you can tell the per- formance will be good.
For comparison, a friend’s stock EasyS-
tar with a 3S 1500 mAh battery weighs over 600 grams; whereas those “Angry - Stars” (without ailerons) come in at about 730 grams. The new EasyStar II is quoted as being about 700 grams. Thus my EasyS- tar Lite is about 20% lighter than a stock EasyStar; and about 35% lighter than the “AngryStars”. In terms of sink rate, since it is proportional to the square root of the weight, that translates into 10% and 17% improvement, respectively. As for flying, this EasyStar Lite flies a treat, climbs well, soars like a bird, and makes a pretty sight in the sky.
PHOTO: TOM JORY
Dave holds the recently completed EasyStar Lite(above left) in a picturesque setting. A bit hazardous for flying. The EasyStar Litein its element (above right)
FLYING MODELS
in a clear blue sky. Weighing in at 470 grams gives the EasyStar Litea distinct advantage in efficiency compared to a stock EasyStar II.
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