Plane 1 - FireFly
Our search led us to www.instructables.com - where we got some detailed plane building plans using readily available parts (pipes, tubes, corrugated boards, thermocol, etc). That's all we needed - print-outs of plans, sheet of 6 MM thermacol, paper-cutting knife, fevicol, clear tape - all from the local stationary shop - to start our scratch built plane.
The first model we build was a foamy called the Fire-fly (also known as Warp). The build was relatively simple and we completed the project in less than 4 man-hrs. At this point we did not have the high-speed motor, servo, or fancy transmitters. We decided to pull the motor from my nephew's toy RC car, purchased a 6x3 propeller from the Indian Hobby Center and proceeded to test the model for its aero-dynamics.
What did we learn - a whole lot indeed! Firstly, our motor was way tooooo slow and did not have sufficient tourque to pull the weight of the light weight foamy. Our model also did not have any glide properties - it simply took a nose-first dive after we chucked it in the air. No wonder it crashed on in's maiden flight. We brought the model back to the drawing table and adjusted the rudder and the tail wing - this made the air-craft more stable and gave it decent glider-like properties.
Plane 2 - SPUD
For our next built, we decided to try our hands at SPAD (Simple Plastic Airplane Design). The design elements of such planes are developed keeping in mind that the modeler should be able to use various easily available plastic derivatives such as a PVC pipe, corrugated sheets (used for display ads outside stores), etc. We researched various forums and settled upon the Micro Slow Stick - with good in-air stability. We wanted a model that we can use for free-flights and then add 2 servos (rudder and elevator), a 3channel transmitter and use as a Thermal Glider. Once we get our hands on a Brushless Motor and matching ESC - we would convert this into an all electric 3 channel park flyer. The Micro Slow Stick serverd our purposed quite well.
We procured the corrugated sheet from a local Banquet Hall (Ridhi-Sidhi - Bangur Avenue, Kolkata), the fuselage was built using a aluminum channel, an old 9Volt battery from Sudeep's collection, few high-strength rubber-bands from the office.
We procured the corrugated sheet from a local Banquet Hall (Ridhi-Sidhi - Bangur Avenue, Kolkata), the fuselage was built using a aluminum channel, an old 9Volt battery from Sudeep's collection, few high-strength rubber-bands from the office.
We wondered the streets of Calcutta searching for servos and high-speed motor - but received no success. Finally, we used my Iphone GPS to locate the last hobby-parts supplier on our list - Kadet Models, Kolkata. The owner, Avdhesh Khaitan was kind enough to speak to us and provided some great advice. He inspected our plane and suggested to increase the tail wing and rudder size. That was a great tip...and it gave the plane more balanced flight. Additionally, we were able to buy some Balsa wood from his work-shop for our next model. Avdhesh also suggested, if we need additional guidance... he would be willing to help.
Plane 3: TUFFY
My third attempt at building a model led me to RCforums, where I found plans and instructions to build a Pusher Prop Model called TUFFY. This model has a Pusher Prop design and a glider like profile, which makes it a great electric plane for beginners like me (especially those who are prone to crashes). My Tuffy's specs are :
Wing Span: 41''
Chord length: 7"
Dihedral: 1.5" (each side or total 3")
Radio Set-up: 3ch (motor, rudder, elevator)
Material: High-density thermocole, fevicol, tape, wooden skeewers, toy-car wheels, etc
Model Weight: 225 gms
Estimated AUW: 550 gms (using brushed motor & NiHm batteries)
My third attempt at building a model led me to RCforums, where I found plans and instructions to build a Pusher Prop Model called TUFFY. This model has a Pusher Prop design and a glider like profile, which makes it a great electric plane for beginners like me (especially those who are prone to crashes). My Tuffy's specs are :
Wing Span: 41''
Chord length: 7"
Dihedral: 1.5" (each side or total 3")
Radio Set-up: 3ch (motor, rudder, elevator)
Material: High-density thermocole, fevicol, tape, wooden skeewers, toy-car wheels, etc
Model Weight: 225 gms
Estimated AUW: 550 gms (using brushed motor & NiHm batteries)
These pictures of the model's progress till its' initial glide test. The model has proved to be a stable during the glide and simple motor tests. I plane to complete this model in the next few months.