|Cutting roughly to length|
|Rough timber and old sprit on bench|
In the photo below, you can see the full set of the Blue Moon's plans on my bench. Although some very detailed plans include an offset table for spars, Tom Gilmer contented himself with a simple drawing, and trusted his builders to pick the dimensions themselves.
What I did was this:
What I did was this:
- Snapped a center line on the timber, using a chalk line
- Drew 'stations' on the plan, one foot apart, labeling them A, B, C, etc.
- Drew the corresponding stations on the timber.
- Picked the diameter of the spar off the plans at each station,
- Transferred those dimensions to the spar
At that point, I had stations and points that I could connect using a batten to draw the curves. I hammered small nails into the timber and bent the batten around them. I could have used a slightly longer batten, to be honest, but it was the best I had on hand, and was just long enough. Note that only the out-board part of the sprit was going to be round. The in-board part would be left square. So the curve was only cut on part of the timber.
|Laying out curves|
It was quite a chore to run the heavy timber through my bandsaw, but my friend Tony and I just barely managed it. It was one of those many jobs which are so fraught that I forget to take pictures of the process, but here is the result of the first two cuts. If you click on the photo to enlarge it, you can see the centerline and stations.
|First curves cut on bandsaw|
|Both curves cut|
After consulting my boatbuilding books, I found a simpler, faster, and probably more accurate method. Basically, you use a saw to make cuts in the corners, cutting down to the lines, and then chop the waste out with a sharp chisel.
Here are the corners cut, with an ordinary saw.
|Chopping them out|
|Transition from round to square|
And meanwhile, Cabin Boy needed some sprucing up for spring. By 'some', I mean two weeks of scraping, sanding, painting and varnishing, with the early spring weather not always cooperating. But it is always worth it to see him looking fresh and happy each spring.
|Cabin Boy's spring refit complete|
Next Up: Varnish or Oil?