I have a Shearwater Sport Sectional that I built about 3 years ago (with much gracious assistance from this forum). It’s great and I use it often. I’ve noticed however that when I leave it assembled for multiple days at a time there’s a tendency for the main sectional gaskets to adhere to the mating surfaces of each section, making separating the sections very challenging. I’d like to learn if there’s any way to mitigate this.
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I built a sectional because it’s impossible to move a full-size kayak via the elevators in my building, and prohibitive to store in my unit. The sectional design solves this problem perfectly. There are however periods of time when I prefer to just leave the boat assembled, usually strapped to the top of the car, for various periods of time when I expect to take it out again soon. So, it may stay assembled for days/weeks at a time. The longer this duration, the more likely it is for the gaskets to aggressively adhere to their surfaces. I’ve had times I thought I may never get the sections to pry apart. I know that a small amount of water gets between the gaskets and the sectional surfaces during normal use (no matter how tightly I’ve cranked down the star-knobs), and I assume this moisture is interacting with the varnish in some way, leading to adhesion over time. All mating surfaces are varnished normally with multiple coats of Interlux Schooner. I do clean all surfaces pretty carefully each time I disassemble.
The only solution I’ve found it to fully disassemble the boat (and remove and dry-out the gaskets) on every use. If this is the only option I’m certainly willing to live with it, but I wanted to see if anyone has any other insights.
Maybe consider completely removing the varnish from the mating surfaces and leaving bare epoxy? Since when the boat is assembled the mating surfaces see no sun and if you’re storing it indoors they see no sun (or no direct sun) during storage. It sounds as if the varnish may not be needed. Removing it would eliminate the water/varnish glue.
Laszlo
Or waxing the surfaces really well?
I am curious. When you did get them apart after drying, was there any indications of damage to the surface…either foam particles that stayed stuck or lifting/damage to the varnish?
I’m not exactly sure what the gaskets/joint looks like but I have used a heavy silicon valve grease made by DuPont in the past. It’s heavy enough to hold the gaskets to the surface but allowing for relatively easy separation. Apply the grease to the section press the gasket into it. It’s dielectric so it’s great to use on a variety of applications including electrical.
@Howard_Spira, after a few intense cases of sticking I did notice a bit of cloudiness developing on the varnished surfaces that touch the gaskets. My theory is that the minor, but prolonged, moisture exposure softened a thin outer layer of the varnish. The only way I could remove this cloudiness was with denatured alcohol, which I suspect just stripped away that thin outer layer.
So, I guess the right long term approach here is to do what Laszlo suggested and remove the varnish at the end of the sections. I hope a simple epoxy surface would be largely immune to this issue. I wondered if that varnish was really necessary when doing the original finishing and just decided to do it to keep all surfaces consistent. I guess that was a minor mistake, and one of those things you can only really learn with experience.
In the meantime I am interested in that suggestion from David and Doug to use some sort of coating on there. I definitely need something that’s inert against varnish. @Doug_Finlayson is that grease easy to clean off?
Yes, it should be easy just using a cloth or paper towels. The less you use the better results you will have. It’s essentially a clear non petroleum based food grade grease. It should hold the gaskets in place until assembly. It will also extend the life of the gaskets and help preventing water intrusion.
I have a take apart Passagemaker Dinghy, which uses a black rubber gasket. The boat is painted (Behr porch paint) rather than varnished. Early on, we did have some trouble with the parts sticking together. Sprayed everything down with silicon spray and haven’t had the least trouble since. We used to take the boat apart only for storage in the winter, but now the sections stay together with the boat on a little flatbed trailer. Last season we took her apart, and still no problems.
I’ll definitely try the Molykote 111. From what I’ve read, and what Doug said, it seems like the best/safest option while those surfaces are varnished. The idea of just using silicon spray is also pretty interesting, and that’s arguably cheaper/easier. I’d be a little worried about repeated over-spray causing issues with other surfaces that may be refinished later, but I’m also probably overthinking that.
