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**Modifying balsa sticks   **Installing Ikara Props   **Installing Teflon washers 
**Ribs & Airfoil    **Winding a rubber motor
Turnertoys sells all supplies referred to on this page at our balsa or supplies pages. 
     Additional excellent advice about trim is available here. 
The article discusses lift and angle of attack, among other topics.  Read it!!

Try this experimental idea for better performance.
     When a motor stick is under the linear and torsional load of a fully wound motor, it may bow or twist slightly. This results in a change in the angle of the stabilizer relative to the wing, and may cause erratic performance during the critical first seconds after launch. Symptoms include
1) airplane dives on launch.
2) airplane rotates (rolls) left and dives at launch (added wash-in on the left wing can help)
3) airplane hardly climbs and flies in "pylon turns" at relatively high speed.
4) airplane climbs slightly during the last seconds of flight then enters a stall.
     Tom Sanders has offered a truly elegant solution. Instead of attaching the  tailboom to the end of the motor stick, use a longer tailboom of sufficient thickness and attach it at the front on the top of the motor stick, approximately where the prop hanger is mounted. This isolates the stab from distortions of the motorstick caused by motor loading.
 
Taper-sanding balsa sticks
If you are building a Sorcerer, you may want to replace the motor stick with a 1/4" sq balsa stick, and use a longer motor stick and tailboom. Try a 1/8" square stick for tailboom. Most sticks and spars can be tapered to the end, left thick in the middle, to maximize strength and reduce weight. Breakage is caused by flexing past a material's elastic limits. Bending stress is maximal at the center of a span, so ends can be thinner.  Almost any stick in a kit or plan can be tapered to improve strength/weight, except the thinnest (e.g.,wing spars). Start with a heavier stick and taper to make weight or even lighter.  
     Use sanding block or hold stick flat on sanding sheet on table with finger pressure to be sure sanded side remains parallel and square. Do not taper the surface where stabilizer or tailboom will be attached - sand on other side. Do not sand where wing will be attached. 
    Some non-commercial high performance plans call for longer distance between prop and stabilizer, using longer tailbooms, and motor sticks as long as 14+". Read the tournament rules and ALWAYS BE SURE YOUR DESIGN IS LEGAL! 

		You can use a rocking motion so more wood is removed progressively from center to end. If stick is thin, sand from center toward end only, not back and forth, to avoid breakage.  BE CAREFUL NOT TO SAND END THINNER THAN YOU WANT!  Be patient and check progress and measure frequently. Count strokes so equal amount of wood is removed from both sides.
		Notch motor stick on both sides to receive  Ikara prop hanger. A similar section is cut for rear motor hook. Cut gradually and check fit frequently.  If you take off too much wood, you cannot put it back! You can do finishing touches with jeweller's file. Lightly shave notch so thrust angle is correct and sides are straight, flat and parallel. Shape stick for maximum contact with plastic part.
		Note slight angle on center section to provide counterclockwise prop thrust angle during flight. IF YOU HAVE NOT CARVED WOOD BEFORE, YOU SHOULD PRACTISE ON SCRAP FIRST. Slow, accurate work will pay off. Ikara prop hanger installed on tapered motor stick.  NOTE: We have found that mounting hanger on a small block of balsa added to motor stick to increase clearance between stick and rubber motor allows more even unwinding.
Similarly shape section of motor stick where the plans call for rear motor hook. Glue plastic parts with Cyanoacrylate, epoxy, or 2-part urethane.		When glue hardens, simply plug prop in and attach motor. Use rubber O-rings to attach motor to hooks.
Tapered 1/4 x 3/16 motor stick with hanger and hook

Glueing plastic parts to balsa:
You cannot use Cellulosic glue such as Ambroid, or water-based glues to attach plastic hanger. Use cyanoacrylate (CA), epoxy, or 2-part Urethane (Potentially messy and requires accurate mixing - not for the unskilled). Score mating surfaces of plastic hook or hanger with sandpaper, file, or Xacto knife to hold glue. 

Ikara Props:
1. Our Ikara Props are now pre-assembled with bearing, shaft, and motor hook. It is designed to plug into included matching prop hanger. A rear motor hook is also included. Use a larger motor stick than provided in Sorcerer (see above) and taper and cut notch to fit prop mount and motor hook. Mark area a little outside where you expect wing posts or saddle to go, and sand only fore and aft of that area. Use sanding block or hold stick flat on table with finger pressure to be sure sanded side remains square. Do not taper the surface where stabilizer or tailboom will be attached - sand on other side.      

2. Adding a Teflon Washer We will be including an envelope of two 1/8" teflon bearings with each order of Ikara Props (2-packs). You will have to disassemble the prop to insert one.
	Use small needle nose pliers to straighten wire shaft.  Use newer pliers in better shape than shown here. Use 2 pliers, one to hold shaft and other to bend hook, to avoid bending shaft.
	Remove red bead and slip on teflon washer with tweezers.  Be careful not to bend or kink washer.
	Replace red bead and check wire for straightness. Straighten it if needed. Replace prop and re-bend right angle. Use 2 pliers to avoid bending shaft. Yes, we did a less-than-perfect job on this sample. You can do better! When you are finished, prop should rotate evenly without eccentricity (moving side-to-side). Mechanics call this "run-out".

HERE'S ANOTHER IDEA, TO USE WITH A "BARE" IKARA PROP (NO ASSEMBLY).  
     Use the wire in the Sorcerer kit or buy a piece to make shaft/hook. Use the plastic prop mount supplied and attached to the small black prop in the sorcerer kit.  Note that the included prop mount has a down thrust, which you may not want. Adjust by shaping stick so that prop shaft is parallel to stick when installed.
     Either bulk up the fore end of motorstick (Sorcerer) or sand end of 1/4" x 3/16" motor stick made from separate piece of balsa. Tapering the ends of 1/4" sq motor stick is the best way. See photos above.

Cutting Ribs for Airfoil on Wings & Stabilizer
Some of the most sophisticated indoor designs use asymmetrical airfoils.  The ribs have more curvature toward the leading edge, flatter toward the trailing edge. Additionally, you can use a shaped spar on the leading edge to provide sharper, less wind resistant leading edge.  The Harlan kits and Sorcerer use  symmetrical ribs. The new Banks Leading Edge uses asymmetric ribs and shaped leading edge. You can cut your own ribs out of 1/16" balsa sheet. 

WINDING A RUBBER MOTOR FOR COMPETITION FLYING: (Also see Last year’s Cruiser directions)
Important: You MUST attach an O-ring (SOLD BELOW) to the tail end of the motor to facilitate removing and replacing the motor from the motor hook for winding.
* Have an assistant hold the front of the model by pinching the nose of the model and the propeller hub with the thumb and forefinger of the left hand.
* With the one hand, the assistant places a cardboard sheet between the motor to be wound and the model. This will protect the model in the event that the motor becomes loose or breaks during the winding procedure. NOTE: Should the motor snap back to the assistant's hand, the assistant must insure that the model is not dropped or released. THE ASSISTANT’S JOB IS VERY IMPORTANT IN CONTRIBUTING TO THE SUCCESS OF THE TEAM.
* The motor must be stretched out approximately 3 to 7 times its normal length (6 to 7 ft) and should be at a 10-30 degree angle away from the plane’s motor stick.
* Begin turning the crank handle in a clockwise motion to wind the motor. For the first few flights put in approximately 300 turns into the rubber motor (divide the motor turns by the gear ratio to arrive at the number of crank handle turns). After the first flight is completed, and adjustments are made, add an additional 100 turns into the motor. As the last of the 100 turns are finished, the person winding the motor should slowly walk toward the rear motor hook so that the rear o-ring is at the rear motor hook at the completion of the winding process. 
THE ASSISTANT NEEDS TO BE SURE THAT THE O-RING IS SECURELY IN PLACE ON THE REAR HOOK PRIOR TO RELEASING IT FROM THEIR CONTROL. FAILURE TO EXERCISE DUE CARE COULD RESULT IN A DESTROYED MODEL.

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