Wednesday, April 27, 2011

The Return of the Dolphin

Long, long ago, Eolian used to have a figurehead:  a beautiful brass dolphin mounted between the bowsprit and the beakhead.  Unfortunately, he had to come off when we rebuilt the bowsprit.  And he has been languishing in the shop ever since.

Recently, however, the guilt I felt each time I had to move him on the workbench to make room for yet another project became overwhelming, and I made *the dolphin* the next project.

First I ran him over the buffing wheel.  This got the corroded sections cleaned up and made him gleam once again.

Next, he spent a few days hanging from the overhead handrail getting several fresh coats of varnish.

Now the interesting part begins.  He is held in place with two very long stainless lag bolts that pierce him and run into the beakhead and the bowsprit (he's metal - he cannot feel pain).  Of course, the hole in the beakhead is still there, but there is no hole in the new bowsprit.  And I won't just drive the lag bolt in there without at least a pilot hole.  So, how to get a pilot hole in the right place and at the right angle?

My answer was to mount him in place with the beakhead lag bolt.  Then, use an installer bit (this is a *really* long drill bit) to drill a pilot hole into the bowsprit, guided by drilling thru the holes in the top and the bottom of the dolphin.  Because I couldn't get a bit of the right size, I had to settle for a 1/8" bit - too small to act as a pilot hole for a 1/4" lag bolt.  But a great size to act as a pilot hole for the correct size conventional drill bit.  So after taking the dolphin down again, I enlarged the 1/8" hole to the proper size using a regular drill bit.  It was easy to keep it in alignment, since it wanted to follow the 1/8" pilot hole.

Next step:  rot protection of this penetration in the bowsprit.  I put a piece of tape over the hole, and used a hypodermic to inject "end cut solution" into the bore thru the tape, replenishing it as it soaked in.  This took a while.  And several beers.

Final step (well, final minus one): mount the dolphin.  To prevent seawater from getting inside the dolphin and into the bowsprit and beakhead, apply a liberal gob of white polysulphide around each of the holes in the dolphin.  Run the lag bolts in, but do not tighten them.

Wait a day for the polysulphide to cure.

Now go back and finish-tighten the bolts.  In this way, a rubber gasket is created from the polysulphide, and then compressed to make a seal which has the thickness to accommodate any relative movement of the bowsprit, dolphin and the beakhead.

It's good to have him back, up there on the bow and guiding our way.


Anonymous said...


Beka said...

I like the dolphin - nice work!

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