Table of Contents
Advertisement
Quick Links
Instructions for Final Assembly
Thank you for purchasing the new Modeltech Extra 300 ARF. This is a stand-off scale .25-.36 size
model of the full size Extra 300. Aerobatic pilot and aircraft designer Walter Extra developed the Extra
300 in 1987. The Extra's shape epitomized the modern, sleek unlimited aerobatic monoplane.
Utilizing a powerful 300 horsepower 6 cylinder engine, an airframe built of Aluminum, Carbon
Fiber, Plexiglass and Honeycomb materials all added up to a lightweight airframe with a considerable
power to weight ratio. This combination is perfect for aerobatics.
Now you can share the same excitement as the full size Extra pilots. The Modeltech Extra 300
comes factory prebuilt using only the finest grades of balsa, plywood and adhesives. Covering is heat
shrink polyester, just like you would use on a model you built yourself. A molded plastic top deck and
belly pan, molded fiberglass cowl and molded clear canopy help accentuate that sleek, aerobatic look.
The Extra comes complete with all the hardware you need, including a fuel tank, spinner, wheels, C/A
hinges and much, much more. It's amazing that all this can be designed into such a small package,
but Modeltech has done it again. But don't let the small size of the Extra fool you. This Extra is big on
performance, just like the full size Extra it's modeled after. It's also easy to assemble. You'll be doing
lomcevaks and inverted snaps in no time!
Version
V1.0
6-99 MTN
Modeltech ARF Kit # 123672
1
All Contents © Copyright 1999
Advertisement
Table of Contents
Subscribe to Our Youtube Channel
Related Manuals for Model Tech Extra 300
Summary of Contents for Model Tech Extra 300
- Page 1 Instructions for Final Assembly Thank you for purchasing the new Modeltech Extra 300 ARF. This is a stand-off scale .25-.36 size model of the full size Extra 300. Aerobatic pilot and aircraft designer Walter Extra developed the Extra 300 in 1987. The Extra’s shape epitomized the modern, sleek unlimited aerobatic monoplane.
-
Page 2: Table Of Contents
Kit Contents..............2 Throttle Linkage............14 Additional Items Required..........3 Installing the Throttle Linkage.......14 Tools and Supplies Needed..........3 Servo Installation............14 Field Support Equipment Needed........3 Installing the Fuselage Servo Tray......14 Metric Conversion Chart..........3 Installing the Fuselage Servos........14 Wing Assembly..............4 Installing the Aileron Servo Plates......15 Install the Dihedral Brace........4 Installing the Aileron Servo........15 Joining the Wing Halves..........4... -
Page 3: Kit Contents
This instruction manual is designed to help you build a straight, great flying airplane. Please read this manual thoroughly before beginning assembly of your new Extra 300. Use the parts listing below to identify and separate all of the parts before beginning assembly. -
Page 4: Additional Items Required
{1} Hitec 4 or More Channel Radio w/4 Servos FOR 2-STROKE ENGINE {1} Dubro Foam Rubber # 513 {1} Magnum XL .25 - .28 Two Cycle {1} Global Fuel Line # 115923 {1} Propeller To Suit Engine {1} Dubro Fuel Filling Valve # 334 {1} Thunderbolt Glow Plug # 115493 {1} Dubro In-Line Fuel Filter # 340 OPTIONAL ITEMS... -
Page 5: Wing Assembly
Please trial fit all the parts. Make sure you have the correct parts and that they fit and are aligned properly before gluing! This will assure proper assembly. Since the Extra 300 is hand made from natural materials, every airplane is unique and minor adjustments may have to be made. However, you should find the fit superior and assembly simple. -
Page 6: Wing Mounting
brace. Make sure to cover the top and bottom as well the forward bulkhead in the fuselage. Push the wing as the sides, and use enough epoxy to fill any gaps. as far forward as possible. The center of the leading edge should fit tight up against the bulkhead. -
Page 7: Installing The Wing Bolt Doubler
Drilling out only these holes will allow easier INSTALLING THE WING installation of the blind nuts in the next step. 13) Place the wing back into the wing saddle. Se- cure the wing in place using the two 3mm x 25mm 7) Install the two 3mm blind nuts from underneath machine screws and two 3mm flat washers. -
Page 8: Aligning The Belly Pan
10) Using a pen, mark the locations on the bot- ALIGNING THE BELLY PAN tom of the belly pan of the two wing hold down 4) With the wing securely attached to the fuse- screws. The two holes will be located 1/2” in from lage, trial fit the belly pan to the bottom of the wing. -
Page 9: Mounting The Horizontal Stabilizer
5) Attach the wing to the fuselage. Align the When cutting through the covering to remove centerline mark on top of the stabilizer with the cen- it, cut with only enough pressure to only cut terline of the fuselage at the rear. When that is aligned through the covering itself. -
Page 10: Mounting The Vertical Stabilizer
3) While holding the vertical stabilizer firmly in place, use a pen and draw a line on each side of the vertical stabilizer where it meets the top of the PARTS REQUIRED fuselage. {1} Wing w/Ailerons & Hinges {1} Vertical Stabilizer w/Rudder & Hinges {1} Tail Wheel Assembly 4) Remove the stabilizer. -
Page 11: Install The Tail Wheel Wire
cure for about ten minutes. Once cured, the aileron 12) With the rudder tight against the stabilizer, may be stiff and difficult to move. This is normal. rotate the rudder to one side about 45º. Apply six Gently move the aileron up and down about five to drops of Kwik Bond Thin C/A to the exposed area ten times to free it up. -
Page 12: Installing The Gear Bracket
7) Slide one 3mm flat washer onto one 3mm x INSTALLING THE GEAR BRACKET 35mm machine screw. Slide one 50mm diameter 1) Using a modeling knife, remove the cover- wheel onto the machine screw, up against the washer. ing from over the three predrilled gear mounting holes. Two holes are located 15/16”... -
Page 13: Engine Mounting
bracket and into the side of the wheel pant. Do this ALIGNING THE MOTOR MOUNT for both wheel pants. See photo # 20 below. 5) The engine is mounted at a 45º angle in rela- tion to the firewall. The motor mount beams should Photo # 20 be parallel with sides of the engine mounting box. -
Page 14: Mounting The Engine To The Firewall
9) Hold the motor mount assembly up to the over the tubes at the front of the stopper and slide the firewall and double check that the four intersecting 15mm diameter rear squash plate over the tubes at the rear of the stopper. Insert the 3mm x 20mm ma- lines line up with the four predrilled holes in the motor mount. -
Page 15: Fuel Tank Installation
FUEL TANK INSTALLATION 9) Slide the fuel tank into the fuel tank com- PARTS REQUIRED partment in the front of the airplane. The top of the {1} Fuselage Servo Tray D-15 tank should face the top of the fuselage and rest just {3} Aileron Servo Mounting Plates W-24 up against it and the stopper assembly should engage INSTALLING THE FUSELAGE SERVO TRAY... -
Page 16: Installing The Aileron Servo Plates
5) Test fit the throttle servo in the preinstalled 10) Hold the two plates in position and trace servo tray behind the forward bulkhead. The servo around them using a pen. Remove the plates and us- should be mounted with the output shaft towards the ing a modeling knife, remove the covering from just right side of the airplane. -
Page 17: Rudder Pushrod
hole in the servo arm. You may need to make a slight 3) Mount the control horn to the rudder by in- bend in the pushrod wire to allow it to align level serting the 2mm x 15mm machine screws through the with the servo arm. -
Page 18: Elevator Pushrod
11) With the rudder and rudder servo in neutral, into the backplate. Tighten the screws, but do not install the servo arm onto the servo. The arm should overtighten them. You do not want to crush the wood. be positioned perpendicular to the servo and face the INSTALLING THE ELEVATOR PUSHROD middle of the fuselage. -
Page 19: Servo Hatch
10) Thread the wire into the pushrod. You can INSTALLING THE AILERON LINKAGE thread the wire in further, or back it out, until the servo 1) Thread one nylon adjustable control horn arm aligns with the output shaft of the servo. onto each aileron torque rod. -
Page 20: Cowl Installation
6) While holding the blocks firmly in position, use a pen and trace around each block . Remove the PARTS REQUIRED blocks and use a modeling knife to remove the cover- {1} Molded Fiberglass Cowling ing from just inside the lines. {2} Cowl Mounting Blocks D-30 {3} 3mm x 6mm Wood Screws 7) Using Kwik Bond Thick C/A, glue the blocks... -
Page 21: Pilot
14) Apply a couple of drops of Kwik Bond Thin C/A into each of the three cowl mounting holes. This PARTS REQUIRED will harden the wood and keep the wood screws from {1} Molded Plastic Pilot Head coming loose during flight. PILOT ASSEMBLY 15) Slide the cowl back onto the fuselage and 1) Using a modeling knife or Lexan Canopy... -
Page 22: Pilot Installation
6) After the filler has dried, sand it smooth and repeat as necessary until any gaps are completely filled. Paint the pilot head, pilot bust and cockpit to INSTALLING THE RECEIVER AND BATTERY suit your tastes. 1) Plug the four servo leads and the switch lead into the receiver. -
Page 23: Balancing
Moving the clevis toward the control surface will in- but less responsive. Do not fly the Extra 300 be- crease the amount of throw. yond the recommended balance range or an un-... -
Page 24: Preflight Check
Do the opposite if there is not enough throw. The Extra 300 is designed for those pilots who are experienced in flying sport models. It is in no way a C) The ailerons should move 1/4” up and trainer. -
Page 25: Notes
____________________________________________________ In the air, the plane flies like any other sport aero- batic plane. Loops, rolls, low passes and most all ______________________________________________ other maneuvers are all possible. Because of the ______________________________________________ sometimes excessive control throws used for aero- ______________________________________________ batics you must be aware of high speed stalling. This _____________________________________________ is when the airplane is at full power and too much up ______________________________________________... -
Page 26: Trim Chart
After you have test flown and done the initial trim changes to the aircraft, use the Trim Chart below to begin trimming your airplane. Following and adhering to this chart will result in the ability to diagnose trim problems and correct those problems using the simple adjustments shown below. Making these observations and related corrections will result in a truer, straighter and better flying airplane. -
Page 27: Product Evaluation
Simply fold this form on the dotted lines, seal with tape and mail it to us. Do not use staples and make sure our address faces out. 7) Was any of the assembly difficult for you? If 1) Kit: Extra 300 ARF .25-.36 (# 123672) yes, please explain. 2) Where did you learn about this kit? - Page 28 Post Office will not deliver without proper postage Global Hobby Distributors Attn: Customer Service Department 18480 Bandilier Circle Fountain Valley, CA. 92728 Fold along dotted line...
Need help?
Do you have a question about the Extra 300 and is the answer not in the manual?
Questions and answers