Diol-based plastic hulls are better than fiberglass-reinforced plastic (FRP)

A model airplane enthusiast—even if, as in my case, he approaches the water more by accident than on purpose, simply for the sake of taking a walk—shouldn’t go around with blinders on or with his head in the clouds. So Miss Barbara—that’s the name of our successful canoeist—told me a bit about herself, a lot about her daily training, and everything about her Diolen-polyester (DFK) canoe.

Of course, there are still GRP canoes—glass fiber reinforced with plastic, mostly polyester resin, because epoxy is too expensive, no better, and considerably harder to work with. Progressive canoeists, on the other hand, use DFK—Diolen with polyester. This type of reinforcement saves at least 10% in weight and, in addition to improved elasticity, provides greater mechanical strength, especially upon contact with the ground—that is, when hitting stones and rocks. Model airplanes—primarily glider fuselages made of Diolen-polyester—also possess significantly better properties than fiberglass-polyester fuselages. The refractive index is lower; furthermore, Diolen is easier to work with during manufacturing and repairs. Furthermore, short Diolen fibers (scraps) do not create a new “skin-like” sensation, as is the case with fiberglass fabric.

Unfortunately, DFK hulls are not yet available for purchase; you have to make them yourself somehow, which in principle is no easier than building GRP hulls, where, as is well known, producing a single unit is not cost-effective.

Furthermore, caution seems warranted regarding potential intellectual property rights. Visible through the seat opening, the following is clearly legible on the inner sidewall of Diolen boats, e.g., those manufactured by Prijon (Rosenheim): “Reproduction without permission is theft”! Hopefully, this isn’t (for the time being) the reason why the model-making industry still doesn’t offer Diolen hulls—which, as my personal experience shows, are superior to fiberglass-reinforced plastic (FRP) ones?!

Since scaremongering has no place in model aviation, progressive model aircraft builders should turn to boatbuilding companies—such as Klepper in Rosenheim or Wolf Lettman in Duisburg—for Diolen material.

Just how important thermoset reinforcement is—whether fiberglass, Diolen, or even something better—was recently demonstrated by the GDR at the Olympics. No “unauthorized person” could get near the boats from Central Germany, and television reports merely mentioned a “new plastic.” In reality, it was all about the reinforcement. According to legend, the material is also said to be excellent for model aircraft fuselages; but no one in the West knows what this mysterious new fiber is. Well, I think that even with Diolen, model aviation has already made significant progress compared to fiberglass-reinforced plastic (FRP), which remains brittle despite the use of plasticizers.

Despite its optimal properties and proven track record in boatbuilding, Diolen may still seem suspicious to some model aircraft builders, as it is a new material in this sector—at least for now. Why shouldn’t model aircraft building also be able to benefit from other high-tech sports?

After all, GRP technology—which is currently still very popular among model aircraft enthusiasts—is not an invention of the model aircraft industry either. So why shouldn’t model aircraft enthusiasts also take advantage of the progressive Diolen technology?