skin and cross section shape

Submitted bybrillythekid onMon, 05/14/2018 - 14:39

Hi Everyone, 

Building a folder, for the most part according to Tom Yost (Yoswerks) instructions.  On the site PVC is recommended for the skin; and the cross-sections/stations are somewhat concaved (1/2"-3/4"). 

I have nylon material available to me, so my question is this: I understand nylon expands\loosens in water, so would it make sense to leave the cross-sections straight without concaving them or concaving them less than with a PVC skin, or are the concaves in the cross sections advisable also with a nylon skin? 


Everywhere that the skin touches the cross sections is a place for potential rubbing and wear. Also, leaving the cross sections straight would actually create a less fair curve to your hull shape. I have used the PVC skin (not recommended) and Dacron - I would recommend shaping the cross sections just as Tom's plans suggest. 


Tue, 05/15/2018 - 14:07

Thank you Rich.  The thought came up because on the Yostwerks site it says: "Concave Cutouts - To accommodate the concave nature of the skin [PVC] while in the water"; and what I read about nylon is it loosens in the water - sounds to me like the opposite of PVC. But I understand your point, and will make the cutout concave.  

I actually really like the PVC skins.  I've made 4 boats with them now.  I was thinking my newest would have been very nice with a nylon skin but I already had the PVC so I finished it with that.  Enough PVC for one more boat and then I'll probably switch to nylon.  I haven't ever fussed much over making the stations concave and haven't seen a big performance problem with any of mine but it's an easy enough modification to do so why not just make it as designed and get the expected performance?