''COMBI by Thomas Yost''
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COMBI by Thomas Yost

The COMBI Double - A double folder that can be assembled as a single.


The COMBI folding kayak can be assembled as a double, or a single. The benefits of this conversion were to allow me to construct two boats for nearly the price of one, while having all the paddling options that the two kayaks configurations provide. The double version uses 9 cross sections for it's 21.5ft frame, and the single uses 6 of those same cross sections when assembled as a 15 footer.

Construction is of aluminum tubing and HDPE "snap-on" cross-sections. Coaming, footrest, and backrest are of these same materials.

COMBI "Double"

With a 21.5ft length, 26.5" beam, and an estimated final weight of 55lbs., this medium volume double is on the performance end of the touring spectrum. It's moderate rocker and deadrise , will permit good tracking and turning capabilities. Paddlers are spaced 6.5ft apart to allow plenty of room for individual paddling freedom. The double features inwales, and secondary snap-on chines.


An extra set of "snap-on" chines between the keel and hard-chine limit the amount of skin "concave" . Inwales provide additional rigidity required by the added length and width of the double. Neither of these assemblies is required for "single" use.

Assembly time is under 40min.


Conversion/assembly as a double or single is made possible by having a symmetrical hull shape with sections 1-4 being identical to sections 6-9. Assembly of the single is simply a matter of arranging the 6 cross sections in the following sequence. ( 1-3, 7-9.) The addition of Sections 4-6 and associated tubing is required for Double assembly. No additional parts are required for either frame configuration.

Two skins are required, but it's is a small price to pay for two kayaks with the construction time and cost of one.

COMBI "Single"

With a 15ft length ,a 22.5" beam, and estimated final weight of 30lbs, this fairly low volume single should provide lively performance. Assembly time is under 30min.

Folders are already versatile kayaks, but with the addition of this conversion feature, the versatility is extended greatly. Add a folding sailrig and you have the "Swiss Army Knife of Kayaks".

Contributors to this page: Thomas Yost (TDY), Patrick Poirier (PPR), Gerald Maroske (GUM) and Hendrik Maroske (HHM)