Ventus 2c: preparations for building the wings

With the fuselages and tail sections of both the Diana 4 and Ventus 2c well advanced, it’s time to start on the wings. I will do the wings of the Ventus 2c first. All previous wings I built with my mate Andi. These ones I will be doing by myself.

The first step is to mount the cut styrofoam parts to the building board (which takes a lot of measuring), clean them and glue together the upper part, prepare the obechi wood, draw out the layout of the carbon on the obechi (which takes even more measuring) and cut the carbon for all four surfaces.

We always build our wings “upside down”. I will first be doing the two upper parts, and then I will add the spars, in the same step as closing the lower part of the wing. All in all four “vacuum sessions”.

Each wing will be built in one piece. Once the wing is sanded and glassed, I will cut off the two outer segments and glue them back at the right angle.

A few details on how we build our wings:

  • We build the “traditional” way, around a foam core, cut with a hot wire. It allows for a light wing, perfect for the type of flying we do. The foam we use is from Schurg Modellbau in Germany. Our club purchased a truckload of the stuff decades ago, but it’s now running out, so we’ll be looking for a fresh supply – ideas for suppliers in Switzerland are more than welcome!
  • The foam cores are glued onto 0.6mm obechi (abachi) wood. A good supplier in Switzerland for this is RIK Modellbau in Mosnang.
  • We use carbon cloth to reinforce the wings at the front (carbon D-box) and rear (control surfaces), as well as around the wing joiner and underneath the servos. We’ve experimented with different types of carbon cloth over the years. Our favourite is 100gr Carbon Biax supplied by It’s good value, fibres are at a 45 degree angle, and it’s easy to cut and use.