Small point of information: The original poster was thinking of not using
plywood butted end to end with any kind of joint ...scarf or butt or what
have you. He was thinking more along the lines of a cold-molded approach
where the panels were build from 2 layers of 1/8" skin, staggering the
joints as he went. I can't see how your boat would benefit over this by
using butt block joints, from a strength perspective that is. If I am
wrong, please correct me.
Personally, I am completely happy with butt blocks and don't mind how they
look, especially in a small lighter weight boat or when splicing thin
plywood. They can be a real time saver during construction and are fine for
strength. In larger boats, they can be a PITA if on the decking or anywhere
near the fairbody inside the hull because they tend to disrupt the normal
flow of water and it creates a wet dirty area that's hard to keep clean and
dry ...this is Oregon, not Florida, so things often remain wet and dirty if
not designed for easy drainability.
Brian
PS: In the link below for my current project, you will note that I deviated
from the designer's original plan on the side panels. Because of
order-of-construction versus shop size constraints and the pain level
associated with outdoor structures around here, I chose to build the 24'
side panels out of a forward 16' scarfed section and then used a butt block
to join in the last 8' in the aft section. The designer uses all scarfs.
But in this case, the forward scarf allowed a natural bend in a critical
area, while using a built-in-place butt block for the aft section allowed me
to use panel sections that fit in my cramped shop and were easier to install
in-place than scarfed joints would have been. The butt block is in a
straight section of the hull so there is no issue about curvature and
changing stiffnessnes. Although the designer prefers scarfs, he approved my
butt block approach prior to my using it. Decking and bottom panels are all
scarfed, but are also all short enough to be built in my shop. No drainage
issues will exist.
--
http://www.advantagecomposites.com/tongass -- My 22' Tolman Skiff project
http://www.advantagecomposites.com/catalog -- Discounted System Three
Resins products
..
"Jacques" wrote in message
om...
"Chalatso" wrote in message
...
Graduating to my first multi-sheet stitch-n-glue... butt joints with
blocks
are ugly, scarfing will throw off my sheet layout. Can I use a plain
butt
joint, supported on both sides by glass and epoxy?
Chuck
I am the designer of that boat.
Use the butt blocks please.
Do not assume that they are ugly: we work hard on locating the butt
blocks in a strategic spot. Here, the bottom butt block is under the
seat, you can't see it.
The side butt block is right in the middle and looks very appropriate
there. It is a local reinforcement.
Look at the pictures he
http://www.bateau2.com/gallery/NC16/index.htm
Those butt blocks aren;t bad at all.
If you scarf instead of using butt blocks, you will need 2 mores
sheets of plywood because of the width of the scarf . . .
There is another version of that plan that uses fiberglass splices and
produces a longer boat but no scarf version.