Earthen Exposure: kayak mods

Below is a small handfull of modifications I have made over the years to make boats more to my liking for general paddling and self-support. Most of this work was done on boats which are now outdated. I leave this page up for the purpose of sharing and documenting my experiences only. I do not recommend any of these or similar modifications to any kayak, old or modern. They may cause your kayak to become unsafe causing serious injury or death. If you make any of these or similar modifications, to any kayak, do so at your own risk!

Miscellaneous kayak mods

Below are a few modifications I made to the Riot Magnum outfitting circa the inception of the Magnum.

	The weakest part of the seat was further weakened with the factory backband slot (A). This also happens to line up with the weakest area of cockpit rim. To counter, I spaned the slot from under the seat with a 2" wide piece of aluminum (B); fastened it to the seat with 8 rivets; then braced it with foam that rests on the hull. Being that I no longer use the slot (A), I could have done something else here that was more effective. As shown, the gains were likely very minimal.
	Stock, the factory seat moved side to side enough (1.5" each way) that I could feel it while paddling, especially bracing. And the gap between the top of the seat & underside of the cockpit rim created a flex point in its most vulnerable spot. The foam on the top (A) takes out most of the flex while the foam between seat & sidewall (B) nearly eliminates side to side movement. This simple & quick little fix made the boat feel noticably better while paddling. Excellent returns! PS: Gluing hip pads in produces cleaner results than duct tape but, in an attempt to minimize my chemical body burdon as much as possible, I quit using adhesives. Hippie chrome works & is much faster.
	Here are 3 very simple & easy mods. To facilitate egress, I chamfered both sides of the pillar (A). The holes in the bulkheads foam (B) adds a little shock absorbtion. (C) is a bungee cord water bottle holder. I used a plastic tube from a ball point pen to keep the bungee from pullling through the foam. Here's how I did it: poked hole in foam 3" from edge with phillips head screwdriver; pulled it out; inserted pen tube over screwdriver & pushed it in hole; pulled out screwdriver & run bungee through.

The original Riot backband adjustment system creates unnecessary friction. Its geometry also wants to naturally pull the band downward rather than forward. The way it is configured in the above photo, the band is pulled in a straight line and with no friction. Getting this band tight to your back is also far easier and faster than with the conventional ratchet system. To tighten, I simply lean forward and pull rather than ratchet. After numerous configurations, this is by far the best I have come up with. I left the original strap and ratchet in place for a back-up. It can be made operational in one to two minutes. The backband is a modified Riot band...the same one shown here. Tightening is done by pulling on the whiteish colored toggles seen hanging below the thigh braces. The ratchet straps run through toothed spring loaded pieces salvaged from the older Riot thigh strap system (like a ratchet without the ratchet lever). These are fastened to the existing holes used for the thigh brace adjustment and reinforced with aluminum plates.

Here's an old thermo formed seat I cut the back out of (indicated by the red arrows) and reinforced with aluminum. The aluminum against the existing pillar pocket (A) was welded to a 3" wide piece of aluminum which was also part of the 1.25" wide band (B) that wrapped around the back of the seat. This band assembly was then attached to the seat with thirteen rivets as can be seen in the top 2 pics. Finally, (A) was attached to the existing pillar pocket via one 1”x1" aluminum angle (indicated by green arrow) per side and a total of ten 1/8" Ø button head screws.

Cutting the seat like this severely weakened its structural integrity. With the aluminum bracing, it recovered an estimated 85% of its original integrity. I justified the 15% loss due to this particular kayaks unusually high shell strength.

For this seat and boat, this mod worked well. It greatly improved the access and allowed some of the weight to be carried lower and closer to my butt.

Below are some modifications I did to a Dagger CFS including the installation of an old roto molded Wave Sport X seat and building a new backband from an older Pyranha band.

Stock, the CFS was one of the more difficult boats to load I have used. After these mods, it was amongst the easiest of pillared kayaks. The boat also lost two pounds in the process and retained most of its structural integrity... and possibly gained in some areas. Prior to this swap, I cut the back out of the stock seat similarly to the photos above. However, due to this seat's configuration, the overall gains were so small, I ended up throwing it in the trash (recycling center wouldn’t take it).

I cut the top part of the X pillar pocket out (A) to accomodate the CFS pillar (B). To provide extra pillar/seat connection, I extended this pocket towards the stern 3" with aluminum (E). This same piece of aluminum overlaps the seat 3" per side (F) and is attached with 20 rivets. For additional lateral stability, I also extended the pocket vertically (D) to the underside of the cockpit rim & ran a 1/4' Ø bolt through this & the pillar. The nut & head were covered with minicell (C) to prevent snagging or undue wear to my drybags. To further facilitate ease of loading, the minicell was chamfered with a rasp (B) (C).
The padded part of this backband was salvaged from an old Pyranha. I made the rest including the aluminum brackets that attach it to the seat. The red ball inside the circled area is the loose end of the adjustment strap which extends just past my hip when pulled. Once in the boat, I reach behind, grab the ball, pull to tighten, drop it behind & put on my skirt. Simple, light, and fast.
Ready to load. This shows the backband folded out of the way...a process easily done in 3 seconds by loosening the metal cam buckle & unhooking the bungee cords. The red ball on the loose end of the adjustment strap can be seen lying in the center of the seat. I salvaged this ball from a rescue PFD quick release.
(A) indicates the metal cam buckle and (B) the extra long adjustment strap. The red ball on the end of this strap is lying in the stern and not visible in this photo.
This is the hook the backband bungee cords attach to. It's shaped like a T with the top part held to the cockpit rim with four rivets. The slot indicated by the red arrows allowed the aluminum to bend more easily without breaking.
Here's the front pillar connection. I just notched the top area of the X seat (A) enough (2") to accomadate the plastic CFS pillar (B), inserted solid plastic spacers inside (indicated by red arrows) & bolted it together with one 1/4" Ø bolt. Though not sharp, the nut sticks out enough to have cut my ankle in a hasty exit. It should have been covered with chamfered minicell or something similar.

Shaving ounces

The amount which can be saved by swiss cheesing depends on each particular boat. The more plastic there is in the outfitting, the more that can be saved. That said, there's usually no single mod that will justify the time. It's the culmination of many small mods that makes the difference. And even then, it would be rare to save a pound by drilling only. Removing the excess aluminum from the bulkhead (losing adjustability for taller folks) and modifying backbands can reduce the weight further.

Most of the time, you can expect to lose some strength to any piece you drill holes in. To what degree depends on the number of holes, placement, and configuration.






	An aluminum bulkhead I made for a Disco.

top

youtube