I wish you joy with your new kayak! Let me share some of the my experience I've had with mine. Allow me to apologize in advance for the length.
First, context: I've been paddling skin on frame kayaks almost exclusively for about 20 years now. Although there are five SOFs in the rack, my go-to is a de Rijp replica that Harvey Golden built for me in 2002 or thereabouts. This kayak has been very heavily used in both salt and fresh water, in all seasons, and in conditions up to large breaking North Atlantic swells in nor'easters, and steep beach surf. It's also been used in several rescues, sometimes in demonstrations, but often enough in other situations. I mention this as these rescues require dragging kayaks across the foredeck and holding them there while their paddlers climb up, get in, snug up, and are sent off. It's a lot of pressure as well as wear and tear on the kayak. The Rijper has been re-skinned four or five times, and had two light re-builds. But that's in addition to one thorough re-build that Fred Randall did at the end of 2019 which included routing out grooves in the gunwales where the ribs had punctured through the red cedar, and then laminating yellow cedar strips into the grooves for strength; all new ribs; new deck stringers; and another new skin. He brought the kayak back to its original lines. (I'm so very, very, grateful that Fred gave me my old friend back as good as new!). And the Rijper has been back in serious use ever since, year 'round. The point is that SOF kayaks are not static. Rather they are always developing and improving. You can change and re-build them. This was expected in Greenland. With mine, small repairs were always done when the skin was off on mine, lashings were snugged up, and the frame was oiled. My kayak has been skinned with 10-ounce ballistic nylon each time.We've tried several coatings. Once we used Rustoleum, which cracked after a while. I had better luck with Coelan and Cory's Goop. These are both two-part polyurethanes. They remain flexible over time. The Coelan seems easier to apply, but is more expensive. Both of these coatings are pretty tough. The kayak sometimes gets dragged across sand. It has hit branches and rocks. But thankfully, it has never hit anything sharp, such as a sharp shell or a sharp rock. So, I've never had to deal with a cut in the skin. (Depending on what kind of kayaking I'm doing and where, I sometimes carry some repair tape. Duct tape will do.) I do sometimes smooth a little Aquaseal onto the abraded areas of the hull, and into the rigging holes. And I just might try a re-coat with Cory's Goop in the Spring. We'll see. In any case, these are tools that get used and are easily repaired. They are also very string. A paddling acquaintance of mine once rolled his truck with two SOF kayaks on the rack. The truck was totaled. The kayaks were paddlable.
Though I used to paddle fresh water much more often than salt, and even now paddle the ponds here in Plymouth when the tide doesn't serve, there has never been any sign of mold or rot in my kayak. This is true even when the kayak has gone unused for some time. Sand, I'll grant, is the enemy. So, as Kami mentions above, I do everything I can to keep it out of the kayak. I don't wear shoes in the kayak, and rinse my approach footgear off very well before getting in. Sand gets in anyway, of course. So I rinse the kayak periodically with whatever water I'm in, fresh or salt. Certainly I've hosed it many times. The East Greenlanders did have drain holes. I've never tried them. But there's always some water getting in between the tuiliq and the coaming, especially in waves or when you're learning new rolls. Although I've never had any trouble emptying the kayak, I also sometimes think that there might still be some water lurking in the stems. Maybe someone else has some experience with drains. More trouble than they're worth? I'd be curious.
I've never used a sea sock. Nor have I been tempted to. Simplicity and being able to move in the kayak is much more important to me than whatever benefit I can imagine from sitting in a bag. I do use float bags when conditions warrant. Float bags can provide some peace of mind when it's rough. At least once they saved me a great deal of grief when the break from a large wave imploded the skirt of my tuiliq off the coaming. To empty the kayak I had to get in through a steep break to a beach that was littered with boulders. Even if I could have maneuvered enough to miss the rocks. it would have been impossible to empty the kayak and get out of the way of the next crashing wave, had the kayak been full of water. But between the volume of the float bags, and my own volume, there was very little water in the kayak. Maneuvering was straightforward and the kayak was light enough to carry clear of the next wave.
To facilitate getting float bags up to the ends of the kayak, I rig haul lines to the stems before the skins go on. I also lengthen the tubing to the air valve. That way I can pull the un-inflated bags to the end of the kayak with the lines and blow the bags up once they're in place. After paddling, let the air out and drag the bags out with the inflation tubes. My kayaks are all low volume. Split bags seem to work fine and are readily available. But it's not critical as the bags just blow up far enough to fill the space that they're in, right? Just make sure they have eyes in the ends for the lines. And take the bags out of the kayak when you're done paddling to let the kayak get some air. I admit that I only use bags when I feel they're necessary. You may choose otherwise.
Hopefully this helps. I'm sure you'll love your new kayak. Post some pictures!
-- Dan Segal
Hi Dorothea -
A couple suggestions and notes for you that could be helpful in avoiding the sand and mold problems with your SOF.
In regard to the sand - best suggestion is to take care to avoid the sand getting in, as your current issue is more difficult to deal with once it's occurred. I take a minute before putting my feet and legs in to wash off both and have not had a problem.
Dumping out your SOF after each paddle deals with excess water and any sand that may have sneaked in. I can video the next time I dump out if you're a visual learner, but in a nutshell - while the SOF is in the water, take the bow and submerge- taking the water down into the bow. Then rapidly lift the bow up and turn the kayak over, causing the water with the help of gravity to pour out of the qajaq.
On the note on fresh vs salt water suitability for your SOF - I have washed out my qajaq with fresh and salt, and haven't had any ill effects, I do believe that the salt water can be beneficial for the wood - but am unaware as to why freshwater would be detrimental.
When storing my qajaq- I do remove anything I've added in, so I would also suggest you remove the floats for air circulation and drying, and I have used commercial kayak floats in my qajaq.
Google (search internet) for "Sea Sock". It is THE best way to keep inside of SOF clean. You can buy them commercially, and you can make them. I'm not keen on plugs to drain SOF, but having never had one installed, I would be interested for you to report back to let us know how the drain works. I have issue with mold growing inside the qajaq, despite keeping it open, putting it in the sun to "dry", and placing a small fan in the interior. I have put rock salt into the qajaq, to simulate sea water: don't know if that will help with drying or mold.
Ask your builder what he suggests you do for sand and soil.
Several years ago Masik magazine discussed sea socks, and how to make them: check it out in "Archives"
check out this video by Anders (a good guy, knows what he is talking about) regarding sea socks: https://vimeo.com/20056748
I am having a skin on frame qajaq made for me, similar to my Tahe Greenland. I have not had an SOF before, and know from reading other threads that I should not use fresh water to wash the interior of my qajaq. However, I get lots of sand and gravel in my current qajaq, and do not know how to clean it. I have asked my builder, Mark Reuten, to install the plug Brian Schultz uses in a video he made. Will this be sufficient to clean out the qajaq? Should I remove the seat each time I use it, and clean inside it. Do you remove float bags each time? And are there commercially available float bags for a Greenland-style qajaq?