Progression recently approached our head twin tip board designer Franz Schitzhofer to ask him his thoughts on how boards have changed in the recent years and to give us his expert insight.

The question : Foam boards were popular several years ago, why have most companies now switched to a full wood core? 
Here is what he had to say....

Kitesurfing is still a relatively new sport and many shapers involved in the development of products came from a Windsurfing background (including me). The knowledge we had built from developing windsurf equipment was highly useful when starting to design the first kiteboards. 

The main material used for windsurf cores is foam, not wood, and the reason for this is due to the light weight characteristics.

To give you an idea of weight comparison between wood and foam: 

Foam: Used in early kiteboards: 80 – 120kg per cubic meter 
EPS-Foam: Used in modern windsurf boards: 15 – 20kg per cubic meter 
Wood: Used in modern twintips (Pauwlonia): 320 – 350kg per cubic meter 

So there is a huge advantage using foam, instead of wood, to save weight – over 60% lighter. However foam has a big disadvantage – it is not as pressure-resistant as wood. That’s not such a big deal on a windsurf board, as windsurf boards are much thicker than kiteboards. However on a twin tip this lack of pressure resistance can lead to disaster! 

Twin tip riders jump hard and do a lot of tricks! For example take PKRA riders or Ruben Lenten, the tricks are getting harder every year and for the past 2 years or so most pros are on boots, adding extra strain to the board. They’re hurting their bodies and their kite equipment. 

Due to this radical riding, there is a strong load beneath foot pads or boots. This has a consequence, on a foam-board, that after some sessions small pockets and blisters occur. These details can weaken the structure of the board’s materials and in the end it’s always the same result – a broken board. There are ways to avoid these effects with thicker lamination or more sophisticated materials – carbon, kevlar, thick glass fiber – but then the main benefit of foam, less weight, is gone. 

Sandwich constructions, similar to windsurf boards, are a good idea in theory but in the reality of industrial production we have to count every buck and for twin tips a sandwich construction is just too expensive. So that’s the reason why most kiteboard brands use a wood core in their twin tips! We at BEST Kiteboarding use Pauwlonia, Beech and combinations of both materials as a wood core in our twintips. This wood grows in plantations and we force our manufacturers to only use wood that is sustainably managed to save this planet. 

Conclusion – wood is a perfect compromise between weight, strength, pressure resistance and sustainable materials.

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Sent from Jeremy