Convert Guillow Kits to RC

Guillow's Nieuport balsa kit frame

Guillow’s Nieuport balsa kit frame

Most modelers are familiar with the Guillow’s line of balsa model airplane kits. Guillow kits were first introduced in 1926 and were an immediate hit. The boxes have an inviting depiction of the aircraft to be modeled. Guillow kits are updated today with advances such as laser cut balsa as opposed to the earlier die cut process for aircraft parts.

Guillow typical kit contents - note plastic nose cowl and canopy, where required

Guillow typical kit contents – note plastic nose cowl and canopy, where required

The Guillow kits were designed primarily for rubber powered free flight. Some of the kits outlined an ambitious conversion to .020 gas powered engines or control line flight. I actually built a Me-109 with a Cox .020 gas engine and U-control flight. The model flew well, but there was a lot to learn in those early days with adding proper structure updates for the vibration from the glow fuel engine. Not a concern with today’s electric flight.

Building the kit

Guillow kits included clear building instructions and full size plans. A common construction method was employed for all kits with a fuselage half side built directly onto the plans and a balsa wing outline, rib and spar arrangement. If you can construct one Guillow’s kit, you could build them all.

The kits did go together well and the finished airplane was a nice presentation. The recurring challenge is that the average Guillow kit came out on the heavy side for successful flight. Due to this added weight many of the completed kits did not live up to their expectations at the flying field.

ParkZone electronics and electric motor placement over Lancer fuselage plan

ParkZone electronics and electric motor placement over Lancer fuselage plan

With the advent of low cost miniature radio control gear, powerful electric motors and tiny lipo batteries, many modelers are returning to the Guillow line and seeking to convert these aircraft to RC flight. This is an entirely achievable task and can provide a great deal of enjoyment and satisfaction. As an example, see here for my successful conversion of the Guillow’s Lancer to indoor radio control flight.

Underside view of the Lancer showing landing gear and electronic installation

Underside view of the Lancer showing landing gear and electronic installation

Following are some considerations should you decide to convert a Guillow kit to radio control flight.

First, begin with a kit design that will likely emulate smooth, trainer-style flight characteristics. Aircraft models tend to fly and handle much like their full-size counterparts. Fighter aircraft will likely be touchy and responsive on the controls as compared to a Piper Cub. A high wing aircraft is a better, more stable initial conversion candidate than a low wing flyer.

You will have to fit your electronics and motor into whatever model you are converting to RC flight. As these kits are smaller in size, plan ahead to use an aircraft that has sufficient internal volume for whatever control system you intend to install.

Control Electronics

I use the ParkZone microelectronics in most of my indoor flyers. I have a good understanding of how much room is needed for these systems. One of the benefits of doing these conversions is you can adapt your installation as required.

For example, the Lancer has a narrow fuselage width. The ParkZone receiver cannot fit using a normal, horizontal install. The simple solution was to insert the receiver sideways and mount it against the fuselage side, and this approach worked fine.

Guillow's Avenger balsa frame, ready for covering

Guillow’s Avenger balsa frame, ready for covering

While not a huge challenge you will have to plan ahead to construct flight controls. This will include elevators and rudders, and ailerons if required. I use an eyeball estimate for control surface area. Better to have a too much rudder or elevator surface than not enough. Ensure that the controls can move freely without binding in the final installation and that you allow for control rod runs to connect to the servos in the fuselage.

With the smaller size of a typical Guillow model it is a good technique to consider installing the electronics, motor and control rods prior to covering. This makes it a lot easier to make any necessary adjustments without the concern of damaging the covering material.

Guillow's fuselage showing typical former, center crutch and longeron construction

Guillow’s fuselage showing typical former, center crutch and longeron construction

Another design area that you will have to tackle with these free flight conversions is the landing gear. For whatever reason, all of the Guillow kits have landing gear installations that can only be considered an afterthought. I do not think these fragile gear installations would survive a few free flight touch downs, let alone repeated landings and take offs with RC operations.

The landing gear upgrade is an easy one to implement, but must be done. Depending on the size of the model use music wire that is strong enough to support the model without adding any unnecessary weight. You will have to fashion a fuselage lower former plywood doubler to fix the landing gear in place.

Lancer strengthened nose section - supports motor and landing gear

Lancer strengthened nose section – supports motor and landing gear

You will have to add structure and strength to the model’s nose section to properly accommodate the additional stresses from the motor. For the smaller models I employ a 1/16 inch balsa doubler on each side of the fuselage from under the wing midsection to the forward nose. This offers sufficient strength to install a lightweight plywood tray on which you can install the motor.

As a technique to keep weight at a minimum I typically do not install a lot of equipment access hatches. If I do need to get to something inside the model, I cut away the covering.

One access area that will need to be designed in is for the battery, which of course will have to be removed and installed for each flight for recharging. A good location for this opening is the fuselage underside, as this area is typically out of sight. I keep the battery area open to aid in cooling.

Once you achieve success with your initial Guillow’s conversion consider moving up to more advanced aircraft. Recall that you can always increase wing or tail surface areas a bit, or add dihedral for a more stable model without affecting the visual appearance to any great degree.

These unique models add a lot to your modeling experience and allow you to explore a new world of low cost scale radio control airplanes. Give it a try!

 

 

Author: Gordon McKay