Prior to World War II, air racing was a growing interest to airplane enthusiasts. After the War had ended, a new class of air racing was introduced- the Goodyear class, often called "midgets". The Shoestring, which got its name for being designed and built on a 'shoestring' budget was a hot little race plane in this class. Rodney Kreimendahl did the configuration and all the design work on the midget racer, and the Shoestring had its maiden flight in 1949 with and engine loaned to the builder by 1st place race pilot Bob Downey.
The midget racer was the winner of the Goodyear racing class in 1951, but was disqualified in 1952 for flying too low in the Cleveland race to defend its title. After that race, the Shoestring was sold to make-way for an addition to the family and a new house.
Great planes, on the success of the .60 size Shoestring, has added a smaller version to their line-up. This newest offering is a .46 sized midget racer that brings all the fun of its larger sibling to a smaller, more convenient to transport package!
I don't know about you, but I am excited to get started on this airplane!
Out-runner brushless motor 80A ESC 11.1V LiPo battery.
Channels Used: 4 total - Elevator, Aileron, Rudder, Throttle
Items Needed To Complete
4+ Channel Radio and Receiver
4-5 Standard Servos
2 or 4 stroke engine of appropriate size
Thin CA Glue
Small Drill bits
Various Standard Shop Tools
The Great Planes Shoestring ARF arrived in my front porch in a plain brown delivery box. Out of that package, I pulled a very colorful box, with a cover that depicts a scene right from a late-40's air race. With the box top removed, I found a very neatly packed ARF. All the parts are bagged and taped together to prevent shifting during shipping.
Some of the noticeable features are the sturdy fiberglass cowl, the painted scale-looking landing gear and fiberglass wheel pants, and the large removable top, which attaches to a fiberglass fuselage. The Canopy is complete right out of the box, and the painted pilot is already installed! This Great Planes ARF looks like it will go together fast.
The manual is typical of any Great Planes airplane you buy, except for one minor mistake. I'll explain that in detail in the engine mounting section. Whether a kit or an ARF, Great Planes manuals are easy to read, and include very detailed illustrations, which make for an enjoyable building experience!
AILERON SERVO INSTALLATION
Assembly starts with the aileron servo installation. The first step is to plug a six inch servo extension into the servo and secure the connection with a piece of the included heat shrink. Now, the servo can be attached to the cover. One of the nice features on the Shoestring is that the servo mounting blocks are pre-glued to the servo cover. This is a big time saver, and honestly it is my least favorite task when assembling a wing. Make sure to place a shim between the servo and the cover before drilling the mounting holes. The manual instructs you to fold a business card twice, so there are three layers of paper. Once the shim is in place, drill the holes, remove the servo, and thread a servo screw (included with the servo) into each mounting hole. Apply a drop of thin CA to the holes next, and when dry mount the servo to the blocks.
Now it is time to mount the cover to the wing. Tie the pre-installed string to the servo lead and pull the lead through the wing.
Next the cover is put in place, and the four mounting holes are drilled. Once the holes have been drilled, thread an included machine screw into each hole and apply a drop of thin CA. When the CA is dry, mount the servo cover to the wing.
The ailerons are pre-installed (and glued) and have a plywood hard mount installed for the control horn. Attach a nylon clevis to an aileron push rod, and line the assembly up with the servo arm. The mount is visible through the covering, and the horn sits perfectly on the mount when lined up with the servo arm. Transfer the control horn hole locations to the wing and drill the holes, making sure NOT to drill completely through the aileron.
With the hard mounting surface, there is no need to use the backing plate with the control horn. After drilling the holes, thread an included machine screw into each hole, and apply a drop of thin CA. When the CA has dried, attach the control horn to the aileron.
Once the control horn has been mounted, the push rod length is determined. Mark and bend a 90 degree angle in the push rod, slide it through the outer-most servo arm hole, and attach a nylon FasLink. This completes the first wing, and the second is done the same!
TAIL SECTION, TAIL SERVOS, AND PUSHROD INSTALLATION
It's time to mount the tail feathers! Install the wings to the fuselage with the carbon fiber tube and thumb screws. Once secure, slide the horizontal stabilizer through the opening in the tail, and check the alignment. Once satisfied, glue the Stab in place using 30 minute epoxy. Gluing the elevators in place is next, and is standard procedure for CA hinges.
The tail wheel bracket and rudder are installed next, and this is also standard procedure. The manual does instruct you to apply a few drops of oil to the top of the tail wheel wire where it goes through the bracket, so it is not glued permanently in place. The rudder is glued in with CA hinges, and the control surfaces are now installed.
The tail wheel is installed and kept in place with a wheel collar. Now, we move on to the push rod installation. Thread a clevis on to each of the three 36 inch push rods, and slide them in through the openings in the tail. Attach a control horn to each, determine the mounting location, and mark and drill each hole.
Attach the control horns to each respective control surface using the included screws and backing plates, then secure the push rod clevis to each control horn.
Install the elevator and rudder servos in the same manner as the aileron servos. Mark and bend a 90 degree angle in the rudder push rod, cut off the excess, and attach to the rudder servo using an included FasLink.
The elevator halves each use their own push rod. The left push rod is marked and bent, and attached to the elevator servo, while the right push rod is cut one inch shorter, and secured to the left push rod with two wheel collars. Be sure to use a thread locking compound- you don't want these to come loose!
MAIN LANDING GEAR INSTALLATION
The Shoestring comes with fiberglass landing gear legs. The first step is to attach the axles to the gear legs. One minor concern I had with the axles is that the threaded portion of the axle isn't long enough to go through the gear leg, and reach the nylon locking part of the nut. This is easily overcome by putting a little thread locking compound on the axle before installing the axle nut. Make sure to grind flat spots in the axle so the wheel collar set-screws will have a place to 'bite' into on the axle.
The inner wheel collar goes on, followed by the foam wheel, and then the outer wheel collar is secured to the axle. Next the wheel pant is installed using the included hardware. The wheel pant has two blind nuts preinstalled, and the holes in the gear line up perfectly, making these pants very easy to install while being secure.
The landing gear are attached to the fuselage using the included bolts, lock washers, and flat washers. Be sure to apply a drop of thread locking compound to each bolt before tightening.
FUEL TANK INSTALLATION
The fuel tank is installed right before the engine goes in, and assembles easily. Before installing the assembled tank, make a 14 inch strap from the included hook and loop strapping, and thread it through the slots in the fuel tank mounting tray. Now run the fuel lines through the hole in the firewall, and secure the tank with the hook and loop strap and then a balsa stick gets glued in behind the tank also.
ENGINE AND THROTTLE SERVO INSTALLATION
Mounting the engine is very easy. The mount is attached to the firewall with the included bolts and washers. This is where I had a little trouble with the manual. In the manual, the written instructions state to place the face of the prop hub 4 and 7/8 inches from the firewall, but the illustration shows 4 and 7/8 inches to the end of the prop shaft. The correct placement is to put the face of the prop hub at 4 and 7/8 inches from the firewall.
Locate and drill the throttle pushrod hole in the firewall.
Increase displacement in your 40-size model the easy way: just drop in a 55AX engine! You'll enjoy more horsepower for swinging bigger props ? which means improved 3D, precision and sport flying. Best of all, there's no modifications required!
Mounts directly into the bolt pattern for a 46AX.
A diagonally-placed needle eliminates the need for a remote needle valve.
The 5-sided, angular head design looks great and significantly increases surface area for better cooling.
The Power BoxTM muffler has a generous sized chamber and larger sound baffle to significantly reduce exhaust noise without stealing power.
ABL (Advanced Bimetallic Liner) uses two O.S.-developed alloys to provide a durable barrier between the brass liner and piston.
The other item I had a minor concern with was the throttle push rod installation. The manual instructs you to run the push rod outside of the muffler with a bend at the end to reach the throttle arm. Now, in order to achieve this, you have to rotate the throttle arm 180 degrees so it is pointing up toward the muffler. Installation was ok, but when I tried to attach the cowl, the cowl interfered with the throttle movement. To remedy this, I made a bend in the push rod and ran it between the muffler and the engine mount. This route gave me plenty of clearance, and the throttle rotates without any problem.
Because the engine is completely enclosed in the cowl, I chose to add a DuBro Final Fuel Filter to catch anything in the fuel before it got to the carburetor. The throttle servo is mounted next, and is easy to adjust with the included screw-lock push rod connector.
COWL INSTALLATION AND DECAL APPLICATION
The cowl installation is a little involved, but if you follow the instructions, you'll have no problems. You lay out five pieces of tape, and draw lines at the measurements given in the manual. If you take your time, and follow the instructions, you'll drill the cowl mounting holes in the correct locations, and hit the pre-installed mounting blocks. Make sure to thread a cowl mounting screw into each of the five screw holes, and then follow it with a drop of thin CA to harden the threads.
Decal application is very straight forward and easy. Even the large decals are no problem to apply if you follow the instructions and use a soapy water solution. This allows you to position the decal exactly where you want it, and then set it in place by pushing the solution out from under the decal. One neat feature is that all the decals are labeled on the sheet as to where they are to be applied.
Radio installation, or rather the little that is left, is next. For this step, you must make two straps from the remaining hook and loop strap material- one for the receiver, and one for the battery. These straps are run through the slots in the servo tray and secure the receiver and battery pack. I used a small square of DuBro foam under my receiver as instructed, and then secured it in place.
The 7C sits squarely in the middle ground in computer systems. It's a system that offers much of the 9C's set-up versatility matched to 4-channel ease of use. Like all other computer systems on this page, it offers Dial n' Key simplicity for programming, and the 2.4GHz FASST system for an unparalleled RF link.
A few of the features:
Dial 'n KeyTM programming
Mode 1-4 selectable (modes 3 and 4 available via transmitter software)
Large 72 x 32 LCD screen with adjustable contrast
6-character model naming
Digital trims, trim memory, EPA, subtrims and servo reversing (all channels)
Dual/Triple rates* (aileron/elevator/rudder)
Adjustable throttle cut
Advanced Programming Features Specific to Airplanes or Helis
The battery is wrapped in the same foam and secured using the other piece of strap. All the servos are now plugged into their respective slots in the receiver.
Mount the two antennas perpendicular to one another. I glued two short sections of 2-56 push rod guide to the inside wall of the fuselage, and inserted an antenna into each.
The last step to assembly is to install the wings and attach using the included thumbscrews, and balance the airplane. My Shoestring balanced about 1/4 inch in front of the recommended CG point without adding any weight or relocating anything.
The day chosen to maiden the Shoestring was not the best of days weather wise, but this time of year in Minnesota, we can't be too picky. The temperature was around 40 degrees, and the wind was blowing around 12 MPH. As the O.S. .55ax was brought to life, I was amazed at the plane's eagerness to get air-born. The throttle was advanced, and the Shoestring practically leaped off the ground, and was climbing like a rocket!
After a few laps around the field to get acquainted with the plane, I decided to see what it could do. Slow passes, although not really the norm for a plane like this, can be done, but you have to really be on the sticks. As I dropped the throttle and pulled in some up elevator, the Shoestring stalled, but the stall was very controllable, and the plane started flying again with some throttle added back in.
Full throttle passes were done next, and can be described in a single word: FAST!
With the O.S. .55ax on the firewall, the shoestring bolts through the sky like a bullet fired from a high-power rifle! You really have to stay one step ahead of this hot little racer.
Aerobatics can be done with very little effort. Large, graceful loops look beautiful and rolls look like they are done on a string. More complex aerobatics look good too, but that isn't what the full scale Shoestring was designed to do.
After a few more fast "laps" my heart slowed to its normal rate, and I brought the Shoestring in for a landing. This plane is not a floater by any means, but the glide path is manageable. As I came across the far end of the field and over the short runway grass, she settled in quite nicely and landed gracefully.
I was really excited to have the opportunity to review the Great Planes Shoestring ARF. Assembly was straight forward with no real concerns, and the plane looks fast and beautiful just sitting on the ground. The fit and finish of this plane is top notch, and flying it is a blast! While not a good choice for a second airplane, I think any intermediate pilot can fly it without concern, as long as you can keep your heart in your chest. This plane is a must for anyone who loves the feel of adrenaline flowing through their veins, and at $199.99 it's a sweet deal!
Great Planes Model Distributors
P.O. Box 9021
Champaign, IL 61826-9021 www.greatplanes.com
Distributed exclusively through:
Great Planes Model Distributing
P.O. Box 9021
Champaign, IL 61826-9021 www.osengines.com
Futaba 2.4 GHz Radio Systems
Distributed exclusively through:
Great Planes Model Distributing
P.O. Box 9021
Champaign, IL 61826-9021 www.2.4gigahertz.com
Everything For The R/C Hobbyist
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.