Extreme Flight Muscle Bipe ARF User manual

70cc Muscle Bipe ARF
Assembly Manual
Copyright 2021

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. However, 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 with the AMA safety code. It is highly recommended
that you join the Academy of Model Aeronautics in order to be
properly insured and 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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Congratulations on your purchase of the Legacy Aviation 70cc Muscle Bipe!
Inspired by the highly modified Waco known as the Mystery Ship, flown by
the late air show legend Jimmy Franklin, the Muscle Bipe delivers timeless and
classic looks coupled with modern features and performance. Equally at home
flying barnstormer airshow maneuvers as it is flying old school low and slow
3D, the Muscle Bipe's gentle manners inspire confidence for sport flyers and
3D enthusiasts alike.
The 70cc Muscle Bipe features quick connect mechanisms that allow it to be
assembled and disassembled in a couple minutes at the flying field-without any
tools! No more long and tedious assembly and tear down sessions that are
typically associated with biplanes!
The Muscle Bipe features our state-of-the-art construction materials and
methods, resulting in a lightweight, rigid and robust airframe. It features
carbon fiber wing and stab tubes, carbon fiber landing gear and tailwheel
assembly, carbon fiber main wing spars and fuselage longerons, g10/lite ply
composite laminated internals and 2 gorgeous genuine Ultracote (Oracover)
color schemes. Highly prefabricated, including pre-hinged and sealed control
surfaces, the Muscle Bipe can be assembled in a couple evenings.
Because of the work done for you by the skilled workers in our factory, there is
very little gluing required during assembly. Once you glue the G10 control
horns into the control surfaces, most of the rest of the assembly consists of
bolting components into the airframe. This makes for a very quick assembly
process, with most experienced modelers able to complete assembly in 2-3
evenings of relaxed and enjoyable work.
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Tips for 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
or even worse, burn a hole in the covering! 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 may be required to deflect well more than 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 350 oz. inches of torque.
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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. More recently we have
started using the Loctite brand of Hysol epoxies and have grown to prefer
them for their ease of application and clean up.
6. Your aircraft is built using 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.
7. 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!
8. There are several excellent videos that further explain the assembly and
setup of giant scale aircraft on our YouTube channel, breaking down each step
with in-depth explanations and examples. We highly recommend taking the
time to view these videos, especially if you are new to giant scale aircraft
assembly and setup. Follow the link below to access our channel.
https://www.youtube.com/channel/UCC_LyauUOgcTE4oHow93CNA/videos
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Let's get started!
1. When assembling one of our current aircraft, I like to go ahead and get all
of the control horns glued into the control surfaces. I start by lightly scuffing
both sides of the shanks of each control horn that will be glued into the surface.
A sanding block with medium grit sandpaper is ideal for this task.
2. Insert two control horns into a baseplate and temporarily insert them into
the slots in the control surface (each surface's horns are affixed using the same
method, so choose the surface you want to start with and continue this
procedure until all horns are glued in place). Use a fine tipped marker to trace
the control horn. Remove the horns and baseplate and use a sharp #11 hobby
blade to remove the covering 2mm inside the line you traced. Take great care
to only score the covering.
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3. Test fit the control horns and baseplate into the surface and make sure
everything fits properly. Use a high quality epoxy to glue the horns into the
surfaces. I've started using the Loctite Hysol products and glue gun which
makes this process so much faster with less clean up required and less waste. I
like the slow set EA 9462 for this particular procedure. It allows plenty of time
for gluing all of the control horns into place in one sitting.
I first apply glue to both slots, then to both sides of each control horn below the
baseplate. Once the glue has been applied insert the horns into their slots and
press into place firmly against the control surface. Wipe away any excess glue
with a paper towel soaked with denatured alcohol. Set aside to dry. Repeat
this process for all control surfaces.
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Please note: If using a twin 70-76cc gas engine or electric setup it is absolutely
essential to use a pull-pull rudder system to achieve proper CG. This will
require that you glue a set of control horns to each side of the rudder to
interface with the pull-pull system cables. There is a plywood jig included in
the hardware package that aids achieving proper alignment.
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4. While you are gluing, go ahead and affix the rudder to the fuselage, by
applying glue to the hinge holes in the rudder post and to the hinges in the
rudder. Push into place, ensuring minimal gap, and wipe away any excess
glue, paying close attention to the hinge knuckles.
5. Next we'll install servos into the elevators and ailerons and assemble the
linkages as shown in the pictures. We use the Extreme Flight Xcessories black
socket head servo screws to affix the servos to the airframe (link below).
https://extremeflightrc.com/Socket-Head-Servo-Screws--Qty-100_p_3488.html
While the upper wing servos require no servo extensions for the servo lead to
reach the root, the bottom wings will require a 12 inch extension. Attach this
extension to the servo lead and secure with a servo safety clip or heat shrink
tubing before installing the aileron servo into the wing.
Be sure to apply Blue Loctite to all nuts and bolts! There are conical spacers
included in the linkage kits which go between the ball link and metal servo arm
to prevent binding. Also be sure to place a washer on the outer side of each
G10 control horn.
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6. Next let's get the landing gear mounted. There are pre-installed nylon
insert locking nuts in the landing gear mount, making it very fast and easy to
install the main landing gear. Attach the carbon fiber landing gear using 4
4mm socket head cap bolts, inserted through washers, through the gear and
into the locking nuts. Be sure to place a drop of Blue Loctite on each bolt and
tighten securely.
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7. Slide the landing gear fairings into place and mark the landing gear with a
felt tip marker to show where they fit. Remove the cuffs and lightly scuff the
carbon gear for maximum glue adhesion. Use epoxy or "Goop" silicon
adhesive to permanently attach the fairings to the gear. I suggest using blue
painters tape to keep the fairings securely in place while the adhesive sets.
8. Attach the axles to the main landing gear as shown. Place a wheel collar on
the axle and slide the wheel into place.
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9. Attach the aluminum wheel pant bracket to the wood spacer with the
included black wood screws. Retain the wheel with the bracket assembly as
shown. Be sure to use Blue Loctite on the grub screw.
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10. Slide the wheel pant into position and secure with 2 3mm socket head cap
bolts, inserted through a washer, the carbon gear and into the blind nuts in the
wheel pant. Again, use Blue Loctite on these bolts and tighten securely.
11. Pull the outer side of the pant away from the wood bracket and apply a
bead of epoxy to the bracket. This will secure the pant mounting bracket to
the fiberglass wheel pant, making a much stronger assembly.
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12. Drill a hole in the bottom of the rudder to accept the ball link included in
the tailwheel assembly package. Scuff the shank of the ball link with
sandpaper and glue it into the hole with epoxy or medium CA. Slide the
tailwheel tiller arm into the hole in the ball link and bolt the assembly to the
bottom of the fuselage.
13. Now we can turn over the fuselage and place it on its gear and start
mounting components. First we'll install our choice of power plant. If using a
70-76cc twin gas engine, we'll use the Blazing Star 70cc mount. If using the
Xpwr 60 we'll use the Blazing Star XL Standoff set. If mounting the Saito
FG90-R3 we'll use the Blazing Star Standard Standoff set. Drill the motorbox
to accept your chosen power system. The Xpwr 60 and DA-70/GP-76 all share
the same mounting bolt pattern. We used the stock mufflers for our 70cc
install and the Keleo Exhaust ring for the Saito FG90 R-3 radial.
https://ch-ignitions.com/product/keleo-saito-fg-84r3-fg-90r3-radial-exhaust-
ring/
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14. After mounting your engine, install your ignition module or ESC. For
those using a 70-76cc gas engine, install your ignition module as far forward as
possible on the motor box top. If using the FG90-R3 radial engine, mount your
ignition module inside the motor box directly behind the engine, in front of the
gas tank. If using the Xpwr 60 brushless outrunner, mount your ESC on the
bottom of the motor box.
15. The twin gas version of the Muscle Bipe has a location on the bottom of the
motor box to mount your throttle servo, along with a pushrod and hardware to
fabricate the linkage. For the radial version the throttle servo is mounted
inside the fuselage in the designated area on the side of the tank tray and a
sleeved flexible plastic pushrod with fittings is provided. You will need to drill
a hole in the firewall for the pushrod to pass through and secure the outer
sleeve in a couple locations along the tank tray.
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