You may recognize the Razor 3D from a few years
back when it was a Lanier ARF. In fact we have two articles of the original
Razor3D here in the RCU magazine, one of the ARF
review and one electric
conversion by Greg Covey.
Well Lanier RC is no more and you cannot get your hands on a Lanier
ARF, but Tower Hobbies has now brought back the Razor3D in a
new attractive trim covering that can be setup as glow or electric
right out of the box.
The original Razor3D was almost a blend between a pattern and
an acrobatic aircraft that also had surfaces large enough to allow it to 3D.
Just looking at the Tower Hobbies Razor3D, I would venture to say that it would fall in the
same category. It has a long tail and resembles a pattern ship but one
look at the huge control surfaces will tell you that it means business
in the 3D department as well.
So without further delay, lets put the Razor3D together and see what
she is capable of.
Great sports performance
Attractive new trim scheme
Electric or Glow option
Direct linkages
Magnetic canopy for quick battery change (electric)
The
Tower Hobbies Razor3D is shipped in a sturdy box that does not have
much in the way of eye candy.
The double
boxed shipping container does a great job of protecting the contents.
The single piece wing is placed on the top of the box with the rest of
the components secured in a compartment beneath it. All of the
components of the ARF are individually wrapped and taped down.
With
all of the components removed from the box, you can see that the
Razor3D looks like a very common 40 size build which should only take a
few
hours to assemble.
Tower
Hobbies Razor3D
Price: $149.97
Key
Features
Painted
fiberglass cowl, wheel pants and painted composite landing gear.
Lightweight,
all-wood construction is expertly covered with Top lite MonoKote, for
lasting looks.
Short,
direct control linkages simplify set-up and deliver fast, precise
movement.
Includes
Generous hardware package.
Overview
Take a ride on the cutting edge of 3D performance with the Tower
Hobbies Razor, an almost ready-to-fly aerobat whose large control
surfaces supply maneuverability with a capital MAN! Short, direct
control linkages make control movement quick and precise while also
helping to simplify set-up. The Razors lightweight, all-wood
construction comes expertly finished with Top Flite MonoKote film. Its
fiberglass cowl and wheel pants and composite landing gear also arrive
already painted. Tower Hobbies includes a spinner and hardware, leaving
very little else for you to buy before adding your choice of radio and
electric or glow power system.
One of
the first things that you will notice as you open the box is an an
addendum to the manual and some wing foam/tape which is intended to sit
between the wing and the fuselage. As you take a look at the rest of
the components, you will notice the magnetic canopy hatch which also
features a clever latching mechanism. The firewall is pre-drilled and
blind nuts have been installed to receive a glow or
electric mount. A small section has been pre-carved in the
firewall that can be removed if going the electric route to get cooling
inside the fuselage.
The
painted cowl looks great and has a nice big cooling opening in the
front.
A .40 size motor mount is provided along with a nice blue spinner. The
landing gear also looks pretty sharp and it is nice that the wheel
pants are attached using machine screws instead of going into
wood.
The tail
sections once again shows you those huge control surfaces. The Elevator
is composed of two halves that will be joined together by a metal
U-shaped rod allowing for a single servo to control both halves. The
wing is a single piece and has flat tips. I have also been supplied
the Tower Hobbies TS-160 digital servos for this review which should be
more than plenty to power the control surfaces for both precision and
3D flight.
Manual
The
Tower Hobbies Razor3D manual is very nice and describes the assembly
with great detail . Installation steps are clearly documented and
illustrated to help in assembling the ARF as quickly and correctly as
possible. The CG location (130mm back from the leading edge) and the
recommended control throws are clearly documented.
The
assembly start by hinging the ailerons. CA hinges are provided and the
manual recommends that you drill the hinge locations which will create
a channel for the CA to run down and penetrate deeper to allow for a
stronger bond.
Four CA
hinges are used per aileron. I used some T-pins to get the
hinges ready for installation.
The
hinges inserted nicely into the pre-cut hinge slots and I was glad that
I did not have to widen or rework any of the slots.
Tower Hobbies TS-160 Servos
Price: $42.99
Key
Features
For
glow or electric powered helicopters, cars, boats and .20-1.60 size
airplanes
Standard
size servo has dual ball bearings and metal gears and is great for
applications requiring both high torque and high speed delivered with
Digital precision
With the
CA hinges in place, I used some thin CA to set them in place making
sure that I was able to get full deflection on the surfaces before
hand. The ailerons are controlled by individual servos that install in
pre-cut locations in the bottom of the wing. There is a string that
runs through the interior of the wing which comes in very handy to
route the servo extensions. The TS-160 servo leads are actually long
enough to run the entire length of the inside of the wing and come out
of the hole in the middle. I did install 6" extensions to each aileron
servo to allow them to reach the receiver. Installation of the servos
are straight forward and described in great detail in the manual. Once
the servo leads have been routed, the servos are attached by drilling
the wing, tapping the holes and installing the servos in place with
four screws.
With the
servos in place, the control horns for the ailerons have to be
installed. This is achieved by locating the hard mount inside the
aileron, then marking and drilling the location to allow the two sheet
metal screws to screw into the control horn backing plate on the other
side. The connection to the servo arm is then made by using a 90 degree
push rod connector.
With the
servos completed, two nylon wind dowels are epoxied in place. These
will hold the wing in from the front where a single nylon bolt holds it
in place in the rear. To attach the belly pan, I mounted the wing and
taped the pan in place before I marked it.
A
section of covering has to be removed to attach the belly pan and the
manual describes how this can be achieved using a soldering
iron. I opted for a sharp exacto knife made quick work of
removing the covering before using Epoxy to glue the belly pan in
place. Before I glued the belly pan, I did mount the wing back on the
fuselage to make sure that the pan was aligned with the fuselage as
nicely as possible.
With the
pan glued in place and the wing still on the fuselage, work on the tail
section can start by installing the horizontal stabilizer. I was
pleased to see that I did not have to do any further sanding to get the
stabilizer level with the wings.
A steel
U-shaped connector is used to join the elevator halves together. Make
sure you insert this before you glue in the stabilizer. The short
vertical stabilizer is secured in place by wicking some thin CA between
the fuselage and the stabilizer. With both stabilizers glued to the
fuselage, the elevator halves are attached using CA hinges. Epoxy is
used to make sure the steel joiner makes a good bond to the elevator.
The
rudder is attached using two CA hinges and a nylon tab that houses the
tail gear. I made sure I was able to get full deflection on all of the
surfaces with as minimal gap as possible then used thin CA to set
everything in place. I also attached the tail wheel at this time using
a single wheel collar.
The
assembly of the main landing gear is quite quick as well. The provided axles
are attached to the landing gear and the main wheels are held in place
using two collars. The manual recommends that you file flat spots where
the set screws will connect with the axles to make sure that they do
not rotate back off. The wheel pants are secured to the gear using two
sheet metal screws and the landing gears are then attached to the
fuselage using six screws.
One
of the new features that the Tower Hobbies Razor3D has over the old
design is the use of direct linkages in the tail vs the bell crank type
of assembly. The servos for the elevator and the rudder are prepared in
the same fashion as the aileron servos (using 18" extensions) and
attached to the fuselage in the pre-cut slots. About the only gotcha
here is that the rudder control horn has to be modified a bit (which is
covered in the manual) to clear the fuselage at full right deflection.
One other nice feature on the rudder servo linkage is that Tower
Hobbies has provided a nice carbon fiber tube to help stiffen the
rather long control linkage. Once inserted in the control rod, the
carbon fiber tube can actually thread on the control rod to make
sure it does not move around during flight.
O.S. .55AX
Price: $169.98
Key
Features
Same mounting dimensions as the O.S. Max .46 AX
Advanced
Bi-metallic liner process uses a double layer of plating material
rather than one thick layer. This help the metal bond to the cylinder
and makes the plating mode durable.
Power box positionable muffler.
Angular head design offers increased surface area for better cooling.
14.29 oz (405 g) w/o muffler 18.52 oz (525 g) w/ muffer
Recommended Props:
12x7-8, 13x6-7
Crankshaft thread size:
1/4-28
Default Needle Locations :
High Speed: 2 turns out from fully closed Low Speed: 3mm gap between the needle and spray bar at full throttle.
The engine mount has to be trimmed of excess plastic and can be attached to the fuselage using four bolts.
The
manual recommends that the opening of the lower part of the cowl be opened
up for glow installation. I used a rotary tool to make the hole a little larger so that it would clear the carburetor.
The
throttle servo is installed in the fuselage and the control rod routed
through the fuselage. The throttle linkage is made by using a
screw-lock type connector which makes it easy to adjust the center
location and end points overall.
When
it came time to attach the engine, I noticed that the
recommended distance of 4-7/8" from the firewall to the front of
the collar was too
far out. I initially did not pay attention and drilled out the mount at
the recommended location only to find out later that the cowl did not
fit properly. With a replacement engine mount, I decided that I would
place the cowl on first and adjust the location of the engine from
there. What I ended up with was about 4-1/2" from the firewall to the
collar which resulted in a very nice small gap between the spinner and
the cowl. With the engine in place, I installed the tank in the front
of the fuselage using two Velcro ties. I also installed a third line in
the tank to allow for easy filling and emptying of the tank.
The
manual does not show you how to make these cuts so you are pretty much
on your own here. I decided that I would install the muffler after I
installed the cowling so I had to make a large enough hole on one side
and smaller holes on the other to get to the screws afterwards. I also
opened two large holes in the bottom to get access to the glow plug and
allow for cooling of the head. On the other side of the cowl, I opened
an elongated hole to allow access to the high speed needle and
installed a fuel DOT.
As
far as the electronics, I installed the receiver and receiver battery
in the recommended locations and wired everything down with the intention that I would
not be taking the wing off again. Luckily the 50" wing fits nicely in the
back of my SUV so I do not have to deal with field assembly. At this
point, I also applied the wing tape that had been supplied as an
addendum to the manual and bolted the wing in place. With all of the
main installation completed, I installed a 13x4 (regular) APC propeller
on the nose. The cuts on the supplied blue spinner had to widened slightly to fit the 13x4 prop.
When
it came time to balance the Razor3D, I noticed that with all of the
recommended components in their recommended locations, I was about 10mm
on the nose heavy side (balancing at 120mm) although still within
recommended range. I decided that I would fly it first like that
before I started to shift the CG around. After setting the control
surfaces to low and high rates with the recommended exponential, it was
off to the field for the maiden flight.
For
the maiden flight of the Tower Hobbies Razor3D, we went out to Scobee
field (named after the late Richard "Dick" Scobee, commander of the
Shuttle Challenger) in Houston on a hot but calm summer day. As I can
carry the
Razor3D without having to take wing off, field assembly was non
existent.
However for those that will have to take the wing off, all that needs
to be done is to attach the servo leads and then seat the wing and
attach it in place with a single bolt.
Since
the OS55AX was a brand new engine and needed to be broken in, I placed
the Razor3D on the engine break in stands at the field and proceeded
to start the engine. With the glow plug attached and the engine primed,
it did not take too much effort to get the OS55AX started and running
at a fairly rich setting. The manual for the OS55AX documents a very
detailed procedure to break in the engine which I followed to the
letter. After running a tank through on the ground and heat cycling the
engine, it was time to get the Razor3D airborne.
The
OS55AX manual recommends that you run the engine rich, gradually
leaning it out over the course of 10 tanks which seems like it is
forever when you want to get down to business with your shiny new
airplane. This
did however give us the opportunity to take it easy on the first few
flights and get some very nice photos of the Razor3D in low and slow
flight. As we taxied on to the runway for the maiden, I noticed that
the ground handling that the Razor3D provided did not show any bad
manners and that it could be steered with the tail gear in a
comfortable fashion. With the engine still fairly rich, we advanced the
throttle to get the Razor3D rolling and within a few feet the tail
lifted off the ground as the Razor3D accelerated towards a perfect
lift off.
Once
in the air, I did not have to touch the trims and was pleasantly
surprised to find that the Razor3D flew and tracked perfectly right
out of the hole. For the first few flights, we took it easy doing
nothing more than a few rolls, loops and some inverted flight, nothing
that was too taxing on the engine. The Razor3D tracked very nicely
through all of these basic maneuvers and was behaving like a good sport
plane should with only a touch of down elevator required to keep level
inverted flight.
As
we ran more nitro through the engine and started to lean it out, the
OS55AX started to make more and more power and the muffler tone started
to sing. Around the sixth tank or so I did my first knife edge low pass
over the runway and noticed that I had to hold in a good amount of
elevator and aileron to compensate for rudder coupling. On the next
flight, I added some weight to the tail to bring the CG around the
130mm mark and the rudder coupling was drastically eliminated which
made both David and myself very happy as the brought the Razor3D lower
and lower in KE flight over the runway for still photos.
As
we flew some more basic sport patterns, we noticed that the Razor3D
likes to track very straight due to its pattern like tail and can snap
very nicely. Avalanches looked extremely well with the snap on the top
of the loop not causing any loss of airspeed. The OS55AX is a power
house that once broken in and leaned out started to pull the Razor3D
with authority through everything we could throw at it.
When
it comes to 3D (after all, it is named Razor3D), the Razor3D did quite
well but to be honest it is not what I would call an all out 3D
machine. Upright harriers did have a bit of wing rock to them and the
Razor did want to drop a wing at times when steering around with the
rudder but nothing that was uncontrollable. The OS55AX provides enough
power to hover the Razor3D and pull out with authority but since it is
a two stroke, it does take some throttle management to keep it humming.
I did notice that I had to input a little bit more than usual
inputs to try and keep hovers steady. Rolling harriers were also not
that hard to perform but for some reason I just cannot get used to a
low wing airplane doing rolling maneuvers, but that is probably just
me. To aid in the 3D performance of the Razor3D, we shifted the
CG all the way back to 145mm and this allowed us to perform more stable
harriers and hovers but resulted in rudder coupling creeping back in KE
flight. I will probably keep the CG around 135mm going forward as
coupling is more important to me than a tail heavy airframe.
When
it comes to landing the Razor3D, we did not experience any ill manners
from the airframe and setup. The Razor3D has a very good glide ratio
and can be landed on the mains or settled in for a three point landing
without any problems.
Check
out the video to
see her in action!
Tower Hobbies Razor3D (Pilots, Stills & Video: Burc Simsek and
David Smith)
It
is good to see some of the classic airframes of the past being revived
with new face lifts. The Tower Hobbies Razor3D is a great remake of
the original Lanier Razor3D and is now available with an electric
option right out of the box. Although, I did not actually see the electric motor mount in the ARF, if
I had the option, I think I would actually prefer this airframe as an
electric since it would help in preserving the nice cowl. That however
does not take anything away from the fantastic glow setup and with the
OS55AX, you can have all the power you ever need for this airframe.
I
would classify the Razor3D as a hybrid pattern/sport/3D airplane
which probably likes to be flown more as a pattern/sport type airframe
than all out 3D. By shifting the CG rearwards, the 3D capability is
enhanced but at an observed loss of precision especially on KE flight
and increased landing difficulty. I personally like an airframe that
can KE and track very well and in the recommended CG position, and the
Razor3D absolutely delivers in that sense. It tracks through maneuvers
with confidence and can snap very easily and stop when commanded. The
supplied gas tank allows for flight upwards of eight minutes and possibly
even more with conservative throttle usage.
Overall I was very pleased with the Razor3D and it will make a fine addition to my hangar of sport/3D airplanes.
The comments, observations and conclusions made in this review are solely with respect to the particular item the editor reviewed and may not apply generally to similar products by the manufacturer. We cannot be responsible for any manufacturer defects in workmanship or other deficiencies in products like the one featured in the review.
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