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Toothpick

This is the story of how I designed and built the second version of my glider “Toothpick”.

I flew the original version at competitions in 1988 and 1989. The special thing about this model was the very high aspect ratio of the wings.

I already published some data about this model in a previous post. (Contest Flying)

I was very satisfied with the flight performance at the time. Unfortunately, in 1990, I had a collision with a model of my friend Frank Neumann while flying slopes. My “Toothpick” was completely destroyed.

Very soon I made plans for a successor.

I built a new pair of wings out of Styrofoam and Abachi veneer.

Luckily Christoph Sarter still had the negative mold for the fuselage, so we were able to laminate a new one together.

Since I was very stressed by my job as a teacher in 1990, I had to interrupt my work on this model, and provisionally stored the half-finished parts.

In 1994 I joined a group of model pilots who flew F3B competitions. We started working together to make negative molds for our own F3B model. I forgot about my “Toothpick” project because I thought it was no longer competitive anyhow.

After we held a meeting of senior RC-4 competition pilots in 2022, (I reported about it in my “Phoebus” post), I remembered the old parts of my “Toothpick”. They were still lying around in my basement and had survived my two moves to new apartments in relatively good condition. Now I thought it was time to finish the construction.

The leading edges of the wings were sanded to shape and the wing tips were finished.

Root ribs were prepared and glued to the fuselage.

The gaps were filled and smoothed.

The support for the horizontal stabilizer was adapted to the vertical stab.

Before…

And after…

Rudder and horizontal stab were made.

The ailerons were cut out and adjusted. The corresponding servos and push rods were installed.

The servos for rudder and elevator, the receiver and the battery were installed.

The rudder is operated with litz wire, which dates back to when I was building control line models.

The hatch cover is fastened with a magnet.

Here you see the finished product.

The maiden flight was on April 6, 2024. It flies! But I realized that the center of gravity needed to be moved further forward.

During the high starts I constantly had the problem that the glider would break out to the left. Most of the time I was able to correct this and complete the high start successfully. I didn’t manage to do that on the last launch and the model hit the ground hard.

Both wings broke completely. Miraculously, the fuselage and tail units remained undamaged.

I have already started repairing the wings. But it will probably take some time.

I will report on the results.