50 Favorite Building Tips

EXPERT ADVICE FROM THE WORKSHOP

Expert advice from the workshop

In our monthly Tips & Tricks column, readers of Model Airplane News share their advice for making RC aircraft better while saving time and money. To complement the Plans Guide in this issue, the editors compiled 50 of our favorite building and finishing tips from the archives. We hope these techniques make your time in the workshop easier and more enjoyable.

BALSA DENT REMOVAL

If you notice small dents and dings in the soft balsa before covering, fill a small dish with water and use a Q-tip to apply a drop of water on the dent. Lightly heat the area with a sealing iron and the dents will literally disappear in a puff of steam. As long as the balsa is merely dented and not torn or cracked, this will work perfectly.

CUTTING BRAIDED CABLES

When you cut braided metal cables for pullpull control setups, like rudder and nosewheel steering, the ends will often unravel and become frayed. Simply wrap the cable where you want to cut with paper masking tape and the ends will stay orderly and neat.

HOMEMADE FUEL-LINE BARBS

Don’t you hate it when the fuel line comes off inside the fuel tank? It usually causes a dead stick and damage to the model. To avoid this, wind copper wire onto the brass fuel tube and cut the wire with pliers to produce one ring of copper wire near the end. Clean the joint, and solder the ring to the tube. Use just enough solder to form a small fillet around the wire and ring, and let it cool off. Slide your silicone or Tygon gas fuel line in place, and secure with a tie wrap.

90-DEGREE DRIVER

Sooner or later, there will come a time when you cannot fit a regular Phillips screwdriver or a hex driver into your airplane to tighten a screw. Did you know that the small driver bits for your electric screwdriver also fit into a common box-end wrench? Simply find the mating-size wrench and insert the bit, and you can maneuver it into the close quarters in your airplane to engage it with the screw head in question. It works great and also increases the torque that you can apply to tighten the screw.

MAGNETIC ATTACHMENTS

There are lots of great little scale details that can be added to a scale model, but they can often get snagged on something when you move the model or when it’s in flight. The small magnets available from hobby shops and homeimprovement stores make great “attachers” for things like antennae, Pitot tubes, and machine-gun barrels that stick out of the wing’s leading edge. Install a brass tube where you want the antenna or gun with the magnet glued inside. Then glue the matching magnet in the base of the detail and slide it in place, where it stays put. When you are ready to fly, simply remove the fragile part.

PAINT DRIPS

An easy way to avoid messy paint drips around the workshop is to take a rubber band and slip it over the paint can as shown. You can now dip in the brush and wipe the excess paint off the bristles by pulling them over the rubber band, which is stretched over the can’s opening. This tip is great for all brushon paints, including dope and epoxy paints.

SOAPY THREADS

If you are trying to thread a screw into a plywood or hardwood block—for example, for a landing-gear strap— it is often hard to thread the screw into place without wearing out the screw head. The best way to make the screw go into the tight-fitting hole is to apply some bar soap to the threads. The soap lubricates the threads and makes the job much easier. It also helps when it is time to remove the screw. High-powered magnets are available everywhere, from online to most homeimprovement stores. They are strong and compact, and if you attach one to a metal screwdriver, you’ve just made a magnetic screwdriver that will hold a screw in place. This makes feeding the screw into place in your airplane (like for servo mounts) a piece of cake. As an added bonus, they make it easy to pick up loose screws, pins, and nuts on the workbench.

THINK SMALL

When you are custom mixing paints, such as when you are trying to match a camouflage color, think in small amounts. By mixing up small batches using glass jars and measuring cups, you can fine-tune your mixtures without wasting too much paint. If you get it wrong, you throw out an ounce at a time, not pints or quarts. When you do get the ratios correct, write them down and then you can multiply the ratios to mix larger quantities.

QUICK LINKAGE

Here’s a quick way to make perfect control linkages every time. First, switch on your receiver and transmitter so that all of your servos are centered. Next, use a Popsicle stick and a couple of clothespins to hold your control surface straight in its neutral position. (For ailerons, clip the stick spanwise and attach the clothespins so that one clamps the aileron and the other clamps the wing’s trailing edge.) You can now install your pushrods and install the clevises and connectors. Adjust the clevises so that they connect to the control horns, and tighten in place. Remove the sticks and clamps and the job is done.

HOMEMADE SOCKET DRIVER

Need a 3mm socket driver but can’t find one small enough for your application? Sand down the head of a metric bolt, shaving just enough material to leave the new socket-head driver strong. Then take a piece of wood dowel and drill a hole in the center to accept the threads on the bolt. Glue the bolt into the dowel, and in about 10 minutes, you have made a valuable tool. What’s really nice is that the head is so small that you can really get into tight spaces. In addition, the bolt and nut fit nicely and do not have a tendency to fall out.

CLEAN TIPS

When you use a fine-tip brush to add finishing touches to paint jobs and markings, the pointy bristles can be easily bent and deformed while the brush dries. Replacement glue-applicator tips fit perfectly and will hold the fine tip of your brush while protecting it when not in use. The tips are inexpensive and available at most hobby shops.

DRY-ERASE MARKINGS

Here’s a tip from a professional aircraft painter, who notes that dry-erase markers are an easy way to make markings for paint lines, graphics, and lettering that will not bleed through the paint like regular felt-tipped markers do. This works best on a sealed surface rather than on unpainted balsa or ply. Mark the location, add the masking tape, remove the guidelines with a damp cloth, and spray on the paint.

CONTROL-HORN HOLDER

Do you hate drilling holes through the base of control horns so that they can be screwed into place on the model’s control surfaces? No matter how careful we are, our fingers always seem to get in the way and the horn is often not placed correctly. Solve this problem by using a small patch of thin double-sided carpet tape, which holds the control horn securely in place. If you make the patch of tape small enough, it is completely hidden when the control horn is screwed into place.

CORNER ROOM

A very old method of adding reinforcement to glued formers and firewalls is to add triangular balsa stock at the corners. The additional gluing surface strengthens the joints between the bulkheads and the fuselage sides. Often, however, there will be some hardened glue along the seam line, which prevents the reinforcement stock to sit precisely in place. A simple way to solve this is to remove a small amount of material from the 90-degree edge using a sanding block or a razor plane. This allows the triangular stock to fit flush against the mating surfaces.

SLICING BALSA

When you cut balsa sheets to length and try to make the cut all with one stroke of the hobby knife, the exit of the blade will often cause the wood to split along the grain. Here’s a way to prevent this. After drawing a pencil guideline, cut a small nick all the way through the line and make several lighter passes using a straightedge. The small nick at the end of the cut acts like a “stop-drilled hole” and prevents the stresses of cutting the balsa from causing the grain to split. It works great, and you end up with a much neater job.

HINGE SLOTS

Using a Dremel Moto-Saw and a cut-off disc to cut slots in the leading edge of control surfaces is quick, but it’s often difficult to keep the slots in alignment. You can stay perfectly aligned by placing the cut-off disc in a drill press. Use a scrap piece of wood that’s the same thickness as the control surface, and adjust the height of the disc so that it is centered. If you flip the piece of wood and the disc fits in the slot, then you have the correct center alignment.

WING-WALK TAPE

One obvious scale detail that is often left off scale low-wing airplanes is the strip of no-slip wing-walk material often applied to smooth wings next to the cockpit. For giant-scale aerobatic airplanes, use 3M Safety-Walk Step and Ladder Tread. It has just the right texture and appearance to duplicate the strips used on full-size airplanes, and one roll is good for several model airplanes.

WORKBENCH TRAP

Everyone knows the heart-stabbing pain you get when the last screw that you need to finish a task rolls off the edge of your workbench and disappears in some black hole in your workshop’s floor. Save yourself countless heartbreaks by applying a stick-on magnetic strip (used with storm doors to hold windows and screens) to the edge of your workbench. The material is inexpensive, and its attractive force is strong enough to trap those small screws and nuts that, otherwise, would be lost forever.