~MENU~

From a Bare Hull:  Carlins (Page 3)

Curved Carlin:  Final Fitting
Next, I installed the laminated, curved forward carlin permanently, so that I could move on with the remaining carlins.  Before I could do this, however, I had to permanently install the full-width deck beam that is located just forward of (and tangent to) the curved carlin, since the carlin would rely in part on that beam for support.  (Click here for more about the deck beams.)

With the beam installed and securely fastened, I attached the curved carlin piece.  I secured the carlin to the beam with two bronze through-bolts and some thickened epoxy adhesive at the tangent point.  I countersunk the bolt heads deeply for later plugging, and also recessed the washers and nuts on the opposite side of the beam for best appearance and to prevent any head-splitting protrusions.  Then, I attached the two sides of the carlin to the forwardmost bulkheads with more epoxy and 3" bronze screws, through the carlin and into the plywood.

Cockpit Carlins
The bolts and screws held the carlin tightly in place, so I didn't have to wait for the epoxy to cure before I could continue working on the cockpit carlins, which run from the curved piece all the way aft to the after end of the cockpit.  The curvature of this piece was to be pretty much determined by these four fixed physical point:

1.  End of the curved forward carlin
2.  The edge of the cabin trunk at the midships bulkhead
3.  A point on the after bulkheads taken off my design drawing
4.  A point on the full-width deck beam at the after end of the cockpit, also taken off the design drawing

Though I wasn't sure how it would pan out, I had a feeling that simply bending the boards through these fixed points would create a pleasing and appropriate flow to the shape of the carlins--and, therefore, to the shape of the cabin trunk and cockpit coamings, which shapes are directly dictated by the shape of the carlins.

I built the carlins in place using three thicknesses of 3/4" mahogany, for a total thickness of 2-1/4", which matched the size of the forward carlin.  The use of three thicknesses not only would allow a laminated section, which would be strong, but also made would make dealing with the whole arrangement much easier.  Plus, since the carlins needed to be nearly 16 feet long overall, the use of multiple layers meant that I could use the 10' lengths of lumber that I had on hand, and which are common, and simply stagger the joints between layers for a strong end result.  Of course, bending a single thicker piece also would have been much more difficult, so by choosing laminated construction I solved many issues at once.

began laying out the carlins with the innermost piece at the forward ends on each side.  This section was the most critical, as it had to blend in with the curved forward seciton in a smooth curve to create the rounded leading edge that I designed for the cabin trunk.  Parts of the inner edge of the carlins may be exposed in the finished interior, so I wanted these joints to be as clean and tight as possible.  I dry fit each side in place and used several clamps to bend an appropriate curve that blended well with not only the curved section of the carlin, but also with the fixed point where the carlins passed through the amidships bulkhead.  With some trial and error and minor adjustments, I got first one side, then the other side, bent into place.  To hold them in the proper shape through the next few steps of the building process, I added some simple wooden braces between the carlins and the hull to prevent the curves from straightening out at all.  

When I was pleased with these curves, I permanently installed the first sections.  I secured them to the rabbets in the curved carlin with thickened epoxy and four bronze screws, which I countersunk for eventual bunging later.  I further secured the pieces against the midships bulkhead with some cleats to hold them closely to the bulkhead, as intended.  I left the assemblies to cure overnight before I continued with the remaining laminations.

With only these first sections in place, the shape of the cabin trunk became clear.  I was pleased with the shape and the curvature of the carlins.

The next day, with the epoxy in the first joints cured, I continued with the carlins' installation.

Please click here to continue.>