Mark Smaalders Yacht Designs
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express concern about their building skills.
My cruising boats
feature round-bilge hulls that require lofting,
careful setup, and
attention to fairness throughout the building
process. But one need not
be a master craftsman, furniture builder, or a
wizard with your hands
to build one; any reasonably handy person can build
drawn my plans to
simplify the building process as much as possible,
and modern adhesives
-- epoxy in particular -- make perfect fits less
critical in many
areas. Lots of builders learn as they go, and there
are many good books
available to help you through the hard parts.
Building a boat -- and
developing confidence in your abilities and skills
-- is a very
buoyancy gain depends
really on the wood species you're using. Sea water
weighs 64 lbs
/cu.ft., and adding underwater volume with something
that weighs less
results in a net gain in buoyancy. For example, red
cedar is about 23
lbs/cu ft, d. fir 32-36 lbs, etc. Naturally, you're
also veneering the
topsides, which is strictly a matter of adding
weight (not offset by
added buoyancy), and then there's the weight of the
epoxy. The overall
result is beneficial buoyancy-wise with lighter
woods (such as red
cedar), and moves into the negative column with
woods above about 30
lbs/cu.ft. Red cedar is a fine choice and often
available in veneer,
yellow cedar (about 27 lbs/cu ft) is also good, or
you may have a local
wood that fits the bill.
Q. I doubt if I can get anything except western red cedar for the veneers. Any problems with such a soft wood on the exterior?
No problem, especially if you sheath the hull with cloth. I prefer Dynel or Xynole polyester to fiberglass because of their higher flexibility and greater abrasion resistance.
Q. Do you suggest a bead & cove for the strip planking around the bilge. In strip planking would staples delivered from a pneumatic stapler work as well as nails?
Bead and cove strips can help in fitting the strips, though thickened epoxy will easily deal with small gaps. The strip planks could be stapled (in essence the fasteners are there only to keep things in place until the glue dries), though if the hull was ever damaged and water did penetrate the epoxy, you might have trouble with steel staples. I specify bronze ring nails because they'll be there for the life of the boat, no matter what happens. Also, they provide excellent holding power.
Q. How accurate does the lofting have to be?
Small errors (1/8" to 3/16") won't make any difference to performance. They may be noticable visually, but this can be dealt with (especially the topsides) if you're careful about fairing up the molds after setup, but before planking. There is also another chance to fair things after the hull is planked.
Q. I am still having much trouble with the lofting of the transom in regards to planking thickness deductions. Have tried all methods. I have added waterlines to assist but still does not work out. Must I add extra buttocks in this region?
Extra buttocks can help with planking thickness, in that the more lines you have that are nearly normal to the hull surface, the better off you are. But extra butts and waterlines may be most helpful in making sure you have an accurate shape. Deduct planking thickness using whichever lines are most nearly normal to the raked transom.