Balsa Machining Service (BMS) also sells a Gyroc clone kit that uses standard 18mm engines. The BMS kit has the original elastic ties on the flaps.
The illustration to the left (From the ERockets website) shows two notches on the rear of the flaps. A rubber band is set into the notches and over the rudder fins on the wings. This arrangement allows changing the rubber band if it looses elasticity.
The problem with the original Gyroc has always been the weakening (over time) of the flap pull elastic. Even with an engine out of the model the elastic is still under tension. Here's a simple solution allowing removal of the elastic between flights and a change if the elastic stretches out.
Here's my Gyroc with the stretched out elastic. The elastic is weak and doesn't pull the flap up to the rudder fins.
On the right is the elastic looped through the rudder hole. This hole will be cut through to the leading edge making a notch.
The old elastic was cut off.Using a thin razor saw, a narrow notch was cut into the rudder fin from the leading edge down to the original hole.
The hole on the flap fin was cleaned out (but not enlarged) with a small rat tail jewelers file.
More in next post -
I recently acquired a Semroc Gyro - looking forward to building it. My original Gyroc didn’t live near long enough for the elastic to wear out, I don’t remember if the Sky Gods or a rocket eating tree got it - probably built it 1971-72 time frame so after 40-ish years memory fails me!
ReplyDeleteEstes used to give these away as free kits when you spent above a certain amount on your order. I must have built 3 or 4 of these. Painted in a barber shop pole pattern, so it would look cool spinning down. Lost every one. Thought it was due to windcocking, but since others have gotten it to fly straight, might be due to my pre-adolescent building skills, or lack thereof. Ah, memories.
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