The Arctic Tern Project

Volume 6 Issue No. 10 October 2009

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The Beat Goes On

Summer is over and we on the West Coast are enjoying a fantastic autumn but I have to admit to still being a bit low in the enthusiasm department. Nothing drastic, but the well-spring of enthusiasm doesn’t seem limitless anymore. No doubt it’s a result of pushing for completion last summer then missing it. I think it’s a bit like running a marathon; putting on a bit of a sprint to the finish-line then realizing that wasn’t the finish-line at all but just a cross-walk on the road and you’ve still got 3 miles to go. Ah well, the beat goes on.

Last month I did a bunch of noodling about anchor handling, bowsprits, etc. It was kind of fun but this month I’m back to more pedestrian pursuits.

Chainplate Attachment

Chainplates are to be attached with 5/16” bronze bolts. Because of limited selection of bronze fasteners, the only option open to me was to use carriage bolts. I had wanted to use round-head machine screws but these weren’t available. The difficulty with carriage bolts is the old square-peg/round-hole problem. I could convert the 30 round holes in the chainplates to square ones or I could make the square-peg carriage bolts round. I chose to round-off the square-peg part of the carriage bolt.

Now, because there was only one length of carriage bolt available, I needed to cut the threads a little further down the shaft.

And then trim them to length.

I also needed a way to stop them from turning (since I’d filed off the square shoulders) when I tightened the nut so I cut a slot for a screw driver.

In this way I hoped I could apply enough pressure to stop the bolt from turning when the nut was tightened or loosened. It seemed to work ok.

Hatch-slide Runners

Next thing I did was put some additional mounting holes in the brass hatch-slide runners.

Then I bedded the #8 machine screw mounting fasteners in epoxy in the hope of creating threaded inserts.

After the epoxy cured I backed them out. Usually I embed a nut in the epoxy but this time I thought I’d see if the epoxy alone would do the job. Turns out it didn’t as one stripped out when I remounted the brass runners. I’ll embed nuts or brass inserts later.

Treenail Fastening

The next thing I did was deal with the numerous extra holes I’d drilled in the side of the boat while trying out the various rubrail options. Jeez, what a mess. I drew arrows pointing at the ones that I wanted to keep but the rest got drilled out and pegged with hardwood dowelling.

This worked well and I was considerably cheered when I realized that I’d basically just treenail fastened (pronounced “trunnel”, an ancient but still used method of fastening using wood pegs) my hull edge to the interior sheer batten. Nice!

The pegs are easily trimmed with the veneer saw after the epoxy has cured.

I slightly countersink the “keepers” because the ‘glass tends to get pulled away from the underlying wood around these fastener holes (you can just see this phenomenon in the above two photos).

New Anchor Arrives

Alright, last month I’d expressed my frustration trying to figure out a suitable mounting scheme for the 14 pound Delta anchor I’d planned on using. What a behemoth! I decided to give up on it and put in an order for a 4 pound Aluminum/Magnesium Fortress anchor (http://www.fortressanchors.com/). The Fortress arrived and it’s a beauty.

It looks like something made by the aerospace industry while the Delta looks like an early iron-age farm implement. But after some fiddling around it became clear that I was still going to have trouble stowing it on the foredeck in an unobtrusive manner. Hmm…after some careful thought about how I actually planned on deploying the anchor I determined that it made more sense to mount the anchor on the transom. That way it would always be at hand in an emergency and single-handed anchoring would be simplified. It means abandoning the use of the carefully constructed self-draining forward anchor locker and stowing the anchor rode in one of the cockpit lockers but I think this might make sense. I constructed a prototype anchor-holder that would bolt to the outside of the transom.

This could work.

Preparing Rubrails and Toerails

Ok, I’ll let that percolate for a while. Next I began preparing the rubrails and toerails for final glue-down. First step is to soften the sharp edges on the ends a bit.

And then epoxy coat (four coats) the cutouts for the chainplates. The clamp is there to help form some thickened epoxy used to fill some tear-out caused by the router when the cutouts were made.

The next thing I do is figure out where the scuppers in the toerail need to go. I use a small bubble level to find the low point in the side deck.

Then I cut a few scuppers using the router. It’s a two stage process. I first use a square bit to cut the middle of the scupper.

Then use a core-box bit to round the edges.

The final result is good.

Spacing of the scuppers was determined by having to avoid fasteners for the toerail and the jib-sheet t-track. If I end up with a puddle between the two sets I’m going to spit.

While I was messing around with this stuff I filled the divots in the deck that I created long ago when I had to grind out some air bubbles. Nice to finally have that monkey off my back.

Then I sanded down the area where the toerails and rubrails would attach to make sure I’d get a good bond.

At this point I decided I wanted to shave 1/32” off the outside of the toerails because one of them had some fairly deep saw marks and I’d dug the router in a little deep on one when I was putting in the ½” radius round-over. But how was I going to do this on 24’ long pieces that were considerably curved? (a legacy from months spent dry fit to the boat and the fact that the mahogany was bent in the first place). It would be pretty much impossible to put these pieces past the jointer or the RAS and I couldn’t use the thickness planer either because the inboard edge has a 5 degree slope. And I certainly didn’t trust myself with the hand-held power plane!

I solved the problem by constructing this simple attachment for the router. Basically it turns the router into a very tiny hand-held jointer.

The trick is that the right hand side of the wood block (as looking at it in the photo above) protrudes about 1/32” more than the left hand side. This is accomplished by running the block part way through the jointer (up to the notch for the router bit) after the notch is cut for the router bit. With some minor adjustments of the block (the same sort of adjustments you make when setting up a jointer) you can get it to shave off an even amount and keep a nice straight and square edge.

The above attachment should work reasonably well even if the piece being worked on has a bit of a bow but I decided to construct a nice straight board from lumberyard 2x6 to attach the rails to while they’re being worked on.

Ok, so I shaved down the outer (square edge) of the rails. The toerails are each made from two layers (and upper and lower; the lowers being 24’ long each and uppers in two smaller pieces because of the jib sheet t-track) and each layer got the same treatment. The next thing I wanted to do was to try and get the upper and lower pieces to match up thickness-wise before mounting them to minimize the amount of shaping to be done on the boat. I started off by screwing the two layers together on the straight-board (lining up the outboard square edges) and then going at it with the sanding block on the inboard edge (the one with the 5 degree slope).

This worked ok but I wasn’t entirely confident that the width of these pieces was consistent so I made up another router device to let the router make a 5 degree bevel along a straight edge.

I ran this down inboard edge of the lower toerail pieces then adjusted the straight edge back a bit and tested it out on some scrap (to make sure the width of the upper pieces would match the lower pieces) before doing the upper toerail pieces.

Then I modified the 5 degree router device to let me re-do the round-over on the inboard edge of the upper pieces.

This all worked out ok but it was a lot of jerking around mainly caused by the fact that I’d used bent pieces of wood in the first place, that the rails were made up of two layers, and that I’d scarphed together the lower layers before I was entirely happy with their shape and dimensions. Several times I thought of abandoning them and just starting again with some nice straight (and easily bent) Douglas fir. Anyway, I think it’s ok now. One more dry-fit.