Clipper's Vera Cruise Build

Clipper's Vera Cruise Build

Sunday, January 24, 2016

Spray Rails - Part 1

A combination of colder weather and a difficult time in visualizing the finished product have kept me from making more progress. But I am gradually getting the spray rails figured out, and with each step, comes better understanding of what I need to do.

Let me explain this a bit. Spray rails on this boat can be rectangular in cross section from front to back. They can be full width and full thickness as well. However, I feel that would not look as nice as spending some time to add a bit of shaping to the parts.

Specifically, I want the forward end to taper in thickness and in width gradually until the full 1 inch thickness and 1 1/2 inch width. At the same time, I need to insure that the bottom outer edge remains sharp so that it performs as desired. There is the curve of the hull to consider as the part wraps around the hull. I want to insure that the parts line up when viewed from the front while maintaining a pleasant and gradual curve to the aft a section (which is straight). And finally, the upper surface (the side away from the bottom skin), I want to taper into the skin so it doesn't look so clunky.

Here is a drawing illustrating  some of this.

All of this means that there is a lot to think about and for me at least, difficult to visualize until I get it temporarily mounted on the boat. In order to do that, I need the pieces to be long enough. The longest lumber I could get was 16 feet, so some scarfing was required in order to get the full 22 feet needed.

What I have been doing is working on getting the parts temporarily mounted so I can better visualize the end product and get a better idea of where the tapers start and end, as well as how gradual the tapers need to be. Of course the tapered front will need to transition into the more trapezoidal middle and aft sections. Trying to do all of this by myself presents a few challenges since gravity has other ideas about parts off of the ground!

Additionally, since the rails are 1 inch thick, I elected to do them in two laminations of 1/2 inch thick in order to wrap around the hull curve easier. Of course this complicates the tapering since I plan to do this off the boat before the parts are mounted.

The end result, I hope, is a nicely tapered spray rail at the front, gradually blending into the more rectangular sections at the back. At the same time, the rail will still be functional and serve it's intended purpose of deflecting the water while underway. In reality, only the first 2/3rds of the rail performs this function and the aft 1/3 section is purely optional. But I want it there to give a nicer finished look to the boat.

My progress was hampered by one other factor as well. I misjudged how much lumber I would need and am short. It took me a bit to figure out how much extra is needed. This is mainly a problem because I needed at least two full length pieces in order to verify that they both line up at the front. The only way I could get two full lengths was to cut into one of the second lamination pieces to get the additional lumber needed. Otherwise, it will be at least a week before I can get to the lumber yard to get more wood. Didn't want to wait that long.

Anyway, I have all of that worked out now. I've figured out how much of a thickness taper I want and how the top outer edge of that taper will blend into the aft section. Now I just need some more warm weather and time.

So that's it for now. I wish I had more to write about but I am trying to get there. Better to go slow and get it the way I want it than to rush and not be satisfied with the end results. Take care.

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