Extreme Flight RC EXTRA 300EXP User manual

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85" EXTRA 300EXP 50cc ARF
Assembly Manual
Copyright 2019 Extreme Flight RC

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Congratulations on your purchase of the Extreme Flight RC 85" Extra 300EXP ARF! Purpose built for
the multitude of 50cc engines on the market, this brand new airframe is the perfect complement to these
venerable power plants that have been neglected for far too long. Our design team started with a very
specific goal with careful consideration of weight, wing area and performance parameters to make sure
we delivered the ultimate light weight 50cc performance machine. We are happy to report that our lofty
goals for this airframe were not only met but exceeded!
Precise, agile and aggressive yet super stable and light on the wing, the 85" Extra excels in all modern
aerobatic flight regimes. With reduced control surface throws the Extra is a big pussycat and makes a
great sport flyer. Crank up the rates and prepare to be amazed by the truly unlimited potential of this
airframe!
The 85" Extra 300 EXP is loaded with features including advanced use of composites for a super strong,
rigid, yet light weight airframe, carbon fiber wing spars, main gear, tailwheel assembly, wing and stab
tubes. It features a 2 piece removable stab with internally mounted elevator servos. The Extra is
available in 2 high visibility Oracover color schemes with high contrast bottom colors and a pro quality
hardware package including genuine Dubro ball links. Elevators and ailerons are pre-hinged and hinge
lines are sealed with Oracover, facilitating a quick assembly. Experienced modelers should be able to
finish assembly in a couple evenings of relaxed shop time.

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Please take a few moments to read this instruction manual before beginning assembly. We have outlined
a fast, clear and easy method to assemble this aircraft and familiarizing yourself with this process will aid
in a quick, easy build.
Please read the following paragraph before beginning assembly
of your aircraft!
THIS IS NOT A TOY! Serious injury, destruction of property, or even death may result from the
misuse of this product. Extreme Flight RC is providing you, the consumer with a very high quality model
aircraft component kit, from which you, the consumer, will assemble a flying model. It is beyond our
control to monitor the finished aircraft you produce. Extreme Flight RC will in no way accept or assume
responsibility or liability for damages resulting from the use of this user assembled product. This aircraft
should be flown in accordance to the AMA safety code. It is highly recommended that you join the
Academy of Model Aeronautics in order to be properly insured, and to operate your model at AMA
sanctioned flying fields only. If you are not willing to accept ALL liability for the use of this product,
please return it to the place of purchase immediately.
Extreme Flight RC, Ltd. guarantees this kit to be free of defects in materials and workmanship for a
period of 30 DAYS from the date of purchase. All warranty claims must be accompanied by the original
dated receipt. This warranty is extended to the original purchaser of the aircraft kit only.
Extreme Flight RC in no way warranties its aircraft against flutter. We have put these aircraft through
the most grueling flight tests imaginable and have not experienced any control surface flutter. Proper
servo selection and linkage set-up is absolutely essential. Inadequate servos or improper linkage set up
may result in flutter and possibly the complete destruction of your aircraft. If you are not experienced in
this type of linkage set-up or have questions regarding servo choices, please contact us at
[email protected] or 770-887-1794. It is your responsibility to ensure the airworthiness of your
model.

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A few tips to ensure success
1. We are very pleased with the level of craftsmanship displayed by the builders in our factory. Through
hundreds of grueling test flights containing maneuvers that no aircraft should be subjected to, our
prototypes have remained rigid and completely airworthy. Having said that, it is impossible for us to
inspect every glue joint in the aircraft. Take a few minutes and apply some medium CA to high stress
areas such as the aileron servo mounting trays , landing gear mount, anti rotation pins, wing and stab
root ribs, etc.
2. Having survived the journey half way around the world while experiencing several climate changes, it
is not uncommon for a few wrinkles to develop in the covering. Fear not! These are not manufacturing
defects, and are easily removed with a little bit of heat. Use a sealing iron to go over all seams, stripes
and sharp points in the covering scheme. You may want to apply a drop of clear fingernail polish at
the tip of all sharp points to prevent them from lifting. To remove wrinkles use a 100% cotton tee-
shirt or microfiber cloth and your heat gun and heat the covering while gently rubbing the covering
onto the wood with the t-shirt or cloth. Be careful not to use too much heat as the covering may shrink
too much and begin to lift at the edges. Take your time, and a beautiful, paint like finish is attainable.
3. By the time your aircraft arrives at your door step it will have been handled by a lot of people.
Occasionally there are small dings or imperfections on some of the surfaces. An effective method to
restore these imperfections to original condition is to use a very fine tipped hypodermic needle to
inject a drop of water under the covering material and into the ding in the wood. Apply heat to the
area with a sealing iron and the imperfection will disappear. Deeper marks may require that this
process be repeated a couple of times to achieve the desired result, but you will be surprised at how
well this technique works.
4. DO NOT SKIMP ON SERVOS! Your aircraft is equipped with very large control surfaces that deflect
well over 45 degrees. A lot of servo power is required to prevent flutter and to maintain the required
deflection for maneuvers. We absolutely recommend the use of METAL GEARED servos with a
minimum of 400 oz. inches of torque.
5. Use a high quality epoxy for installing the composite control horns. We highly recommend the use of
Pacer Z-Poxy 30 minute formula. We have used this glue for many years with zero failures.
6. You may want to add a bead of RC-56 Canopy glue to the intersection of the canopy/hatch and its
wood frame for additional strength and resistance to vibration. DO NOT USE CA here as it will fog
the canopy.
7. Your aircraft is built using very modern construction techniques and is very light weight for its size.
As with any high performance machine, regular inspection and maintenance is a must. While
disassembling your aircraft after a flying session, pay close attention and inspect glue joints, linkages
and loose covering to be sure the airframe is sound. A few minutes spent doing this will help ensure
airframe longevity.
8. Be sure to put a drop of blue Loctite thread lock on every bolt on this aircraft! Failure to do so may
cost you your aircraft! This includes servo arm screws!
9. The basic assembly process of the Extra is very similar to that of our previously released 50cc and
100cc aircraft. Some of the photos in this manual may be taken from a previous aircraft release if we
determined that the assembly step was illustrated more clearly in these photos.
If repairs become necessary the Ultracote colors used are as follows:
White/Orange/Blue/Silver color scheme: Orange- # HANU877, White- # HANU870,
Midnight Blue- # HANU885, Sky Blue- #HANU875, Silver-#HANU881
Yellow/Blue/Red/Silver color scheme: Cub Yellow-#HANU884 Midnight Blue- # HANU885,
True Red- # HANU866, Silver-#HANU881

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Since the 85" Extra (and most of our other giant scale models) now come pre-hinged and the hinge gaps
sealed, the most time consuming task of the assembly process has been eliminated. This leaves a very
minimal amount of gluing for the assembler, which consists of installing the composite control horns in
the ailerons, elevators and rudder, with the only the rudder hinges needing to be glued. For this reason
we recommend that you spend the first hour or so of assembly completing this task. After this has been
completed the rest of the assembly process consists of installing components into and onto the airframe.
1. Locate the proper control horns and base plates for each flying surface. Place the 2 control horns into
the baseplate and carefully insert them into the pre-cut slots in the control surface. Use a fine tipped felt
marker to trace around the baseplate.
2. Remove the horn assembly and use your #11 blade to remove the covering from inside the ink line that
you traced around the control horn base. Wipe away the ink line with a paper towel soaked in denatured
alcohol.

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3. Scuff the portion of the horns that will be inserted into the elevator with sandpaper.
4. Locate your epoxy, mixing cup, an old pushrod to stir with and a length of nylon cable tie to apply the
epoxy. We have used Pacer 30 minute Z-poxy for over 2 decades with excellent results and zero bond
failures and we highly recommend this product.

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5. Mix a generous batch of epoxy being careful to use equal parts resin and hardener.
6. Use the nylon cable tie to apply epoxy to the slots and thoroughly coat the control horns on both sides
of each horn.

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7. Insert the control horns into the slots and ensure that the horns are properly seated against the base
plate and the base plate is flush against the control surface.

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8. Wipe away the excess epoxy with a paper towel soaked in denatured alcohol, making sure to do a good
job of cleaning the area. Insert a bolt 3mm bolt and ball link into position and confirm proper alignment
before the epoxy sets.

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9. Repeat this process for the other stab half, the aileron control horns and the rudder control horns.
10. Assemble and install the servo mounting grommets. Connect an EF 20 AWG servo extension to each
aileron servo lead (secure with heat shrink tubing or an EF Servo Safety Clip) and install the elevator
and aileron servos in their designated locations. We highly recommend using the Extreme Flight socket
head servo screws to mount your servos. The servo output spline on all of these servos should be oriented
toward the front of the model.

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11. Locate the linkage components from the hardware package and the recommended servo arms for
each surface. Thread a ball link onto each end of the provided turnbuckle pushrods. Install the linkages
for the elevators and ailerons as pictured using the provided 3mm fasteners. Be sure to use the small
conical spacers between the aluminum servo arm and ball link to prevent binding.

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Fuselage Assembly
12. We’ll begin by installing the landing gear. Locate the carbon fiber main landing gear,
4-4mm bolts, lock nuts and washers. Insert the gear into the slot on the bottom of the fuselage and center
it in the slot. Secure the landing gear with 4 4mm bolts, washers and nylon insert lock nuts by inserting
the bolts and washers into the pre-drilled holes in the aluminum gear mounts inside the fuselage with a
long T-handle wrench. Secure with the 4mm nylon insert lock nuts.

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13. The landing gear fairings add a nice scale touch to the aircraft. Slide the fairing onto the gear and
up against the fuselage. Secure the fairing to the gear with "Goop" silicon glue.

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14. Locate the 2 axles, 2 locking nuts, 2 wheels, 4 wheel collars, 2 outer pant supports and plywood
spacers and 2 wheel pants from the hardware package. Place the threaded portion of the axle through
the hole in the landing gear, place a washer onto the axle and secure the axle with a locking nut.

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15. There is a pre-cut slot in the wheel pant to allow it to fit over the axle. You may need to open this
slot with a rotary tool to allow it to slide into position over the axle. Screw the machined aluminum outer
wheel pant bracket to the plywood spacers and secure to the interior wall of the wheel pant with epoxy,
making sure it fits over the end of the axle and positions the wheel pant correctly.
16. Remove the wheel pants and secure the wheel to the axle with the provided wheel collars. We highly
recommend that you file a flat spot on the axle for the wheel collar set screws to seat against.

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17. Reinstall the wheel pants and secure with 2 3mm bolts inserted through the carbon gear and into the
blind nuts in the wheel pants. Be sure to use thread lock on the bolts! Tighten the setscrew to secure the
wheel pant bracket to the axle.

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18. Next let’s install the rudder onto the fuselage. Glue the hinges into the rudder first with epoxy and
allow to cure. Use a pushrod to apply epoxy to the holes in the rudder post and push the rudder into
position and wipe away any excess epoxy with a paper towel and denatured alcohol.
19. Drill a hole in the bottom of the rudder 3 inches back from the front of the bevel to accept the ball
link for the tiller arm. Secure the ball link with epoxy. When dry slide the tiller arm into the hole in the
ball link and secure the tailwheel assembly to the fuse with the provided 3mm bolts. Again, be sure to use
blue Loctite on all bolts!
20. Next let’s install the engine. We have made this process very easy. If using a DA-50 or DLE-61 there
are drill marks laser scribed on the face of the firewall (Please note, the DLE-61 mounting pattern is
slightly different than the DLE-55). If using another engine or electric motor simply download a
template from their website and tape it in place over the centering marks that have been laser scribed
into the front of the firewall. Drill at the location of the mounting holes. For best results I always use a
pointed reamer to accurately mark the center of the holes then start drilling with a 1/16" bit and continue
with progressively larger bits until I achieve the correct hole diameter. This ensures that the hole is
accurately drilled in the correct location and makes a much neater hole in the plywood.

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21. The distance from the front face of the motor box to the motor drive washer is 172mm or 6.8 inches
(this is the length of the DLE-61, the longest of the engines recommended). Because the DA-50 is the
recommended motor we have included a set of machined aluminum standoffs to be used in conjunction
with the stock 2.5" standoffs included with the DA-50 to achieve the proper spacing.

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22. The following photos show the DA-50 and Xpwr 40 mounted on the 85" Extra. We used the full
length Blazing Star XXL Standoff Set to achieve the proper spacing with the Xpwr 40.
***Please note that we removed the laser scribed panels in the F1 former in our electric powered Extra to
allow cooling air to reach the batteries***