Creating the radio antenna wires is essential when building model airplanes. In most cases, this is an added detail which is not included in the scale model kit. Model aircraft antenna wires are commonly built from scratch using one of several techniques. This tutorial will examine how to create this feature using stretched sprue.
Sprue is the excess material that is used to hold the parts of the scale model kit together. For this tutorial, you will need to cut a straight piece of sprue about 4 to 5 inches long.
Light a candle and hold your piece of sprue at about ½ to 1½ inches away from the flame. Holding the plastic at each end between your fingers will allow you to rotate the sprue back and forth while it is being heated. This rotation will allow the heat to distribute evenly along the sprue instead of concentrating it on one spot. After a few seconds you will notice that the sprue will become glossy, it will soften and start to sag. Be cautions to not let the sprue melt completely.
At this point, you can move the sprue away from the candle flame and begin to stretch it. At a careful steady pace, expand the plastic until you have the desired thickness. This part of the process may take some practice. Stretching the sprue too fast will cause it to be excessively thin and weak. It may even snap. However, if you extend the sprue too slowly, the plastic may harden prematurely. At which point, you will no longer be able to stretch the sprue, and it may be too short and thick for a proper antenna. Your goal is to have a nice, thin piece of sprue, perfect for the model aircraft antenna.
Allow about 10 minutes for the sprue to harden completely. Then, cut off the length required for the model aircraft. You can use super glue (e. g. Cyanoacrylate) for attaching each end to your scale model kit assembly. First, carefully glue one end of the sprue and wait about 10 minutes for it to dry thoroughly. The next step is to glue the other end. This will require accuracy as you will need to glue it with the right amount of tension for it not to break. Once again, allow about 10 minutes for the glue to dry thoroughly and you can then cut off any excess sprue using a clipper.
On several aircraft, such as the Me109, there were ground wires running from the main antenna to the fuselage. Replicating these details is necessary when building model airplanes that are historically accurate. You can also utilize sprue from the scale model kit to create these details by following the above technique. Simply glue one end to the main wire using Tenax-7R, which will cause a slight melt in the plastic. Apply a bit of pressure to secure the attachment using tweezers and wait about 15 minutes for it to dry completely. Before you attach the other end, drill a tiny hole into the fuselage of the model aircraft using a pin vise. You can either use a small drop of Tenax-7R or super glue to attach the other end of the ground wire.