In reply to "plywood sidewall measurements", posted by jeff on Mar 4, 2002:
>A winter project, I am trying to restore the side walls of what appears to be a 16 foot tatman boat. The problem I am having is measuring up the plywood so I can get the appropriate sized side walls. I am sure there is a method but all I can find is the madness. I seem to be off only by an inch. How do I angle the cuts?? Please help!
If this is "HIGH SIDE" boat, then each side piece came
from a separate 4x16 panel. The left-overs from those
side pieces would have been used to make an 11 or 12 foot
pram.
But your boat is more likely a 16 standard, which
means both side pieces were made from one 4x16 panel,
by snapping (and cutting) a
diagonal line down the middle of that 4x16 panel.
28" at one end and 20" at the other end is common.
(28 + 20 equals 48) So are variations of those cuts, one
or two inches more or less at each end. I used 30
and 18 on my old white water boat: the sharptail.
The diagonal cut down the middle of the panel forms the gunwale edge for both sides.
The chine edge is the straight line from the outside
edge of the original 4x16 panel.
PUNCHLINE:
cut a 4' by 4" by 1/4" plywood strip. Butt that strip
along the chine of the boat, at the front end, on one side....so the strip bends
to the shape of the chine and extends out
past the front end of the boat. Now you need two more
hands (or a helper). This plywood strip now extends
the line of the chine out past the front of the boat.
Mark the spot on the plywood strip immediately adjacent
to the front of the chine....where the chine slants upwards
toward the prow of the boat. Use your third and fourth
hands to hold a big sheet rock square at right angles
to the plywood strip.....slide that square back and forth
until the top of the square intersects the prow of the boat.
Now make a second mark (on the plywood strip) at the
edge of the sheet rock square.
The distance between the two pencil marks on your
plyood strip coorespond to the trianglular cut on
side panel at the front of the boat.
Repeat on the rear, to get the angle cut at the transom.
There are alternatives:
A)
It sounds like you want to replace the old plywood sides.
Why not remove the gunwale on one side, pull any nails or screws
and pull one side panel off. You'll have to do that anyway.
Then use the old side panel for a pattern.
Replace one side, then do the other.
B) Don't replace the old plywood. Pull off the outside
gunwale. Sand the outside. Round off the chine slightly.
Glass the outside of the boat. Now take a sledge hammer
and beat the ribs out. Sand the inside. Glass the inside.
....ribs belong on the barbeque, not inside a boat! :-)