Saturday, September 12, 2009
Forward Cabin Sole
The forward cabin is painted, the water tanks are installed, the firing lumber is bolted to the frames, and now it's time to install the forward sole. Sole is to a boat what a sub floor is to a house ( it is to me).
I've had to make the choice of screwing the plywood sole down directly down to the steel flange I welded to the frames or build the steel frames up with 2x lumber, then screw the plywood down to that lumber. I will loose 1.5" of headroom by using lumber, but I feel as if I'll also loose a lot of future complications by using lumber vs straight to the steel. Using a firing strip over the steel flange costs me some headroom, but it also gives me more square footage on the floor since I've raised the floor profile and allowed the plywood to "slide" more outboard against the frames. It's amazing how much more room I have since the sole grew outboard when I mocked up the sole framing system. Screwing the plywood directly to the steel in my opinion will make lifting pieces of the floor a real pain in the ass years down the road as screws rust and break. I'll end up with about 6' 2" of headroom once the finished ceiling is installed. This 6' 2" seems to be my minimum as some areas will be a little more ( 6' 7" in some areas). I'm 5' 11" tall and I'm totally happy with the headroom I"ll end up with.
The forward cabin are is where my cabin will be, the kids cabin, and the common bathroom/shower shared by both cabins. Both cabins will be carpeted and the bathroom/shower room will be hardwood or tile.
I'm using #1 southern yellow pine as my firing lumber, and CDX for as the plywood on the sole. The firing lumber runs perpendicular to the frames and is screwed to the frame flange using a self tapping screw of sufficient size and thickness. Even though the salesmen who sold me the self tappers said I would not have to drill a pilot hole, I found things went much faster by drilling a pilot hole. I also used polyurethane adhesive to glue the firing lumber down to the frame flange. I don't want to rely totally on the self tapping screw as I could see the lumber shrinking, the screw getting loose on the lumber, and a squeak developing. It if for all the reasons I just listed that I think the adhesive will give me some a little better job.
I've also had to make a decision on how I'm going to frame my partitions that will make up the cabin walls. My current boat just uses plywood stood on edge for the partition. This boat is much bigger and has more in her regarding systems and things like wiring and plumbing. I posed this question on metalboatbuilding.org and after receiving the usual good comment, I decided to frame the partitions out of 2 x 3 lumber. The reason I've had to decide this now is because I want to be able to remove all of the cabin flooring without having to remove any partitions. For this reason I'll have to frame the cabin sole in a way that allows the sole to be supported from below while the partitions remain in place. I also have to frame in all my access panels in the floor for access to water tank valves and whatever else I need to maintain below the floor. In a nut shell the cabin sole is basically made up of lots of small pieces that fit together to make the sole system.
I knew where all the access panels had to be located so framing those areas of the sole required very little layout. The partition walls on the other hand would take some more thought. I decided to handle this by framing and installing the sole, then once the sole was complete I will be able to get more precise with the various cabin partitions and cabin components. Once I new where most everything will go regarding living space, I will put layout lines down on the sole and alter the sole to accept the framing above. Doing it this way allows me days to ponder locations and do mock up's to see how things fit. Now is the time I start fighting for every square inch so I want to make sure it works for me and works for the boat. Most of the decisions I'm making have me giving most of my consideration to how easy things will be to service and maintain.
I screwed the sole down with a # 12 stainless steel wood screw using a tapered bit with a counter sink that had a depth stop so all the counter sinks are at the right depth.
The sole is now complete and I'm loving how much better the boat feels now that I can walk around on a firm flat surface. The sole is very solid and has no give or squeak as I walk across it. My next step will be to start the framing of the interior partitions so I can have all the cleats and nailers installed prior to insulation.