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Silent Running
 
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On Thu, 2 Dec 2004 19:22:03 -0800, "John Holtrop"
wrote:

One approach is to clean up the old hatches, glue up any open joints, and
sand the insides well. Then turn the hatch upside down and fiberglass all
inside surfaces. I used one layer of 1.5 oz. matt followed by three layers
of 8 oz. cloth. Trim the glass around the edges of the hatch and varnish
inside and out. My hatches are 20 years old and have had no joint problems.
Another option is to cut away most of the top, tape a waxed piece of plywood
over the outside of the cutout, then glass the insides. When the plywood is
removed the fiberglass will form a translucent window.

"Bernard Randall" wrote in message
...
I am at the planning stage of replacing some deck hatches on a sailing

boat.
The framework is mitered, to prevent endgrain being open to the sea, but

as
these are stepped on they also need to be strong.

I see the altenatives being miters with routed slots for loose tongues, or
mitered mortice and tennons. Anyone have any experience with this type of
work?

Thanks.

BernardR




Any half lap mitre joint will still leave half of the end grain
showing on one side of the joint as will a dovetail - but dovetails
are used where one side of the frame is carried by the other side, I'm
not sure if that is the case here. If mitred tenons are used the tenon
must not be a through tenon or you still get end grain showing, but
will give you a strong joint - not easy to form though. A mitre with a
biscuit or a loose tongue will not be so strong but is probably the
simplest.

However, if you cover the wood with epoxy I don't see what long term
problems you would have by exposing some end grain. It's just a
question of maintenance and as James says it is not as if the joints
are exposed too much.