With the rudder, centerboard, and centerboard trunk built and my spars well on the way to being finished and ready to put away, I finally get to start working on the keel. Also complete are initial coats of epoxy on a lot of large pieces like bulkheads and then multiple smaller pieces like floors. All of these are things that are easier to do before the hull sucks up all my room.
Reading other blogs, there seem to be two aspects of the keel build that have given some people trouble, or at least a little heartburn. I’ll give my thoughts and what I learned from CLC.
Two Concerns
- Maintaining a straight keel
- Cutting a fair curve on the noseblock
Straightness
Beginning just aft of the trunk, the keel width will begin a taper that will continue all the way to the end of the keel. You know this of course from reading the manual. It’s in this tapered section that some people have wound up with their keel curving to starboard or port. Or, maybe the port or starboard side doesn’t taper at all and only the opposite side tapers. This all sounded very bad to me and so I was eager to figure out how it might happen and how to avoid it.
CLC. I contacted CLC about this and their response was very helpful in putting me at ease. I am paraphrasing and generalizing here but essentially I was told, “don’t sweat it so much.” There’s only so much the keel could actually curve and it’d be hard to notice any performance difference while sailing. Made me think about the princess and the pea.
Performance aside, I guess an asymmetrical keel might cause some weirdness when stitching up the hull pieces. CLC didn’t address this particularly and I didn’t follow up. Their general response I thought was pretty clear, “don’t overthink it.” Their advice was to put a little half inch blocking under the aft end of the keel while gluing up. This will keep you from clamping the keel completely flat to your bench and therefore maintain your symmetrical taper.
I’m not saying I don’t care about a symmetrical taper. I’m still going to fret over it. But before glueup, it’s a real load off knowing that if I pop a string after curing and it’s not perfectly straight…it’s ok.
Noseblock Curve & Cuts
Page 34 of the manual describes how the top of the noseblock needs to be cut such that it follows the gentle curve of the keel sides. Again, in reading various blogs I have run across some people describing how this cut being too steep or shallow has caused problems later on in the build.
CLC. I asked them if they had a specific measurement to offer, such as height from bottom of keel to top of the forwardmost end of the noseblock. I was not given any such measurement, for the reason that it’s such a small slope as to make that precision difficult if not impossible to adhere to when working with a piece that’s being hand-shaped. As with the keel straightness, I was essentially told, “don’t worry about it so much, just do your best.” However, it was pointed out that leaving it proud might cause more problem than cutting it too low. If too low, the gap will be filled when a fillet is added as seen on Page 212 of the manual. If too high, stitching hull panels and floor piece could be difficult. My personal intuition however is the exact opposite of this. Seems like erring on the side of too high is the way to go. I can always shave down later, but I can’t add wood back.
As of this writing I have already made this cut and it looks like a good, fair curve to me. I guess I’ll know for sure later on.
Frankly, where I felt the most uncomfortable wasn’t in getting the feel of the curve but in tracing the dang line onto the noseblock. If you drag your pencil along your curved, thin piece of wood, how do you know you’re getting a line that is plumb with your thin piece of wood? The noseblock isn’t flat and your pencil itself has some width that has to be accounted for. It may be hard to describe but get it set up and you’ll see what I’m talking about. It’s easy to imagine how you could wind up drawing a line that is at least a quarter of an inch or more off the curve. In the end, I used my bevel tool in lieu of a pencil. It’s rigid and thin, so I just drug it along my thin batten, scratching a line on the noseblock instead of drawing one. I think that worked well and I feel good about it. I’ll try to remember to report back here on this post later if I’m proven terribly wrong.
2 replies on “Keel Hand-Wringing”
Hi, Martin!
I read on your blog that you’re worried about the evenness of the keel. I made my keel in several stages.
1 – glued the sides to the trunk on a flat table, aligning them symmetrically. When the glue dries, you can glue other details, relying on this base.
2 – glued the noseblock using clamps.
3 – glued the keel block. At the same time, I controlled that the sides were symmetrical. I put the trunk on the floor so that the keel block was at the top. Then I used pushpins and pulled the thread from the nose to the end of the keel block. This helped keep the symmetry. At first I tried it on without glue, and when everything matched, I smeared glues and clamped sides to keel block with clamps.
4 – assembled the stern of the keel.
I hope this helps you.
This will take more time than in the instructions, but will give you the opportunity to control the evenness at each stage.
[…] other builders have done, I took this in several stages and did a lot of dry fitting in between. A previous post discussed a couple of areas I wanted to be particularly cognizant of. I’m happy to say that […]