Harden cardboard - is that possible?

Hardening can extend shelf life, not just for paper and cardboard models. This can also be useful or necessary in some other areas. The possibilities for this in individual areas are revealed in this article.

Hardening paper

Especially in modeling, where a lot of paper is used, one has long been looking for ways to make paper a little stiffer and more resistant. The same problem arises with (thin) cardboard. Also, it is often not resistant to bending or resistant enough.

Soak in superglue

For paper models, this is traditionally done by simply soaking individual parts in superglue. As soon as the glue has hardened, a biegefestes, also waterproof part, which behaves like plastic (even when painting).

As suitable as this method is for paper and for very thin board, it naturally reaches its limits with larger components or thicker board. For this other methods have to be used.

Hardening of larger cardboard or cardboard parts

Apart from the use of thicker or sturdier boards, it is above all the construction method that makes it possible to "stiffen" individual parts. But often very thoughtful constructions and multiple folds are necessary.


One way to subsequently cure finished objects or components can be synthetic resin. When applied in many thin layers, it hardens the part very well.

As a model for the effectiveness of this method could well serve the good old Trabbi. The "racing cardboard" showed over decades that you can produce quite durable structures with synthetic resin. Whether this method is appropriate in a particular case, but then you have to decide each.

Tips & Tricks

The most ideal is probably to find a combination of construction (stiffening) and coating when it comes to larger parts. Thus, the stability is highest compared to all mechanical loads at the end. In many cases, one must also pay attention to the fact that it is necessary to additionally waterproof the cardboard so that it does not soften when exposed to high humidity.

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