plug on boat & rot?
 

hi again,

I've got yet another interesting question which some of you with more
experience can likely say a few words to... I was out testing my project
boat on the trailer, and ensuring the bilge pump would work right by putting
the plug in the boat and filling the back end with a few inches of water.
Well the bilge pump works great, however, when putting the boat plug in I
felt that the wood between the inner and outer fiberglass was a wee bit
slimy and the hole perhaps not as narrow as I'd like to have to ensure the
plug stays in securely.

What can I do here to fix this up?

An idea was to get some fiberglass resin and put a thin coat in the hole as
to seal things, narrow up the hole width, and strengthen the inner hole for
the plug.

Or perhaps a newer plug would be a big thicker...

btw, the boat is a 70's era 15.5 fiberglass.

I feel that the rest of the transom is fine, just this part around the hole
seems to be a bit questionable.

thanks
Chris

You might get away with your idea for repair.
I think you would be better off if you did a more thorough check and repair
of the transom. A boat that old might have hidden damage to the wood that
you won't see unless you start poking around. I think I'd seriously consider
cutting away the transom up to 2" all around the drain hole for inspection.
If everything's OK, you can rebuild that portion and install a new drain
fitting. If you find more rot, you can schedule the time for more repair.


"Chris" wrote in message
.. .
hi again,

I've got yet another interesting question which some of you with more
experience can likely say a few words to... I was out testing my project
boat on the trailer, and ensuring the bilge pump would work right by
putting the plug in the boat and filling the back end with a few inches of
water. Well the bilge pump works great, however, when putting the boat
plug in I felt that the wood between the inner and outer fiberglass was a
wee bit slimy and the hole perhaps not as narrow as I'd like to have to
ensure the plug stays in securely.

What can I do here to fix this up?

An idea was to get some fiberglass resin and put a thin coat in the hole
as to seal things, narrow up the hole width, and strengthen the inner hole
for the plug.

Or perhaps a newer plug would be a big thicker...

btw, the boat is a 70's era 15.5 fiberglass.

I feel that the rest of the transom is fine, just this part around the
hole seems to be a bit questionable.

thanks
Chris

It's too late to do any more than slightly slow the problem by sealing
the exposed wooden surfaces of the drain hole.

If you like this boat and plan to keep it, you will want to cut the rot
out of the transom. Be sure to go a few inches beyond the point where
you "think" the rot ends when scarfing in the new piece. You should be
able to cut away part of the fiberglass on the outside of the transom
and spoon out the punky wood, cut a new piece of the best marine ply
you can find, and then glass up the exterior again.

This is a great chance to learn from the bad practice of the original
builder. Any hole drilled through a wooden member- transom, stringer,
etc for the purpose of draining water should have the edges sealed up
to prevent water from wicking into the surrounding area and promoting
rot. If it were my project, I would cut the drain hole large enough to
accept a drain plug with a bronze collar fitting. Seal the edges of the
hole with a layer of glass and resin, and then bond the bronze collar
into the sealed hole- perhaps using epoxy.

One rot gets a foothold, it is relentless. Transom rot on small boats
is fairly common, and as most are outboard powered it is double
trouble.

Chris wrote:
hi again,

I've got yet another interesting question which some of you with more
experience can likely say a few words to... I was out testing my project
boat on the trailer, and ensuring the bilge pump would work right by putting
the plug in the boat and filling the back end with a few inches of water.
Well the bilge pump works great, however, when putting the boat plug in I
felt that the wood between the inner and outer fiberglass was a wee bit
slimy and the hole perhaps not as narrow as I'd like to have to ensure the
plug stays in securely.

What can I do here to fix this up?

An idea was to get some fiberglass resin and put a thin coat in the hole as
to seal things, narrow up the hole width, and strengthen the inner hole for
the plug.

Or perhaps a newer plug would be a big thicker...

btw, the boat is a 70's era 15.5 fiberglass.

I feel that the rest of the transom is fine, just this part around the hole
seems to be a bit questionable.

thanks
Chris

Most boats have a brass or stainless insert that is epoxied into the
hole. It basically looks like a short piece of pipe with one end
beveled out. This may be missing, and would account for the plug being
loose feeling. Also, the plug is usually adjustable, just turn the
lever a couple of turns, try again.

Chris,
The drain plug should not go directly into the aft end. Not only will it
leak, but the water will wick through the plywood and rot it. You need to
buy a 1-inch brass tube and epoxy it into the drain hole. Now the rubber
expansion plug will fit snug.

Here's one.
http://www.outdoorsuperstore.com/sto...=DRAI N+TUBES

You can make your own after a visit to a plumbing supply store. In a pinch,
you could use a piece of PVC, but because of the thickness of the material,
you'd need to enlarge the hole.




"Chris" wrote in message
.. .
hi again,

I've got yet another interesting question which some of you with more
experience can likely say a few words to... I was out testing my project
boat on the trailer, and ensuring the bilge pump would work right by
putting the plug in the boat and filling the back end with a few inches of
water. Well the bilge pump works great, however, when putting the boat
plug in I felt that the wood between the inner and outer fiberglass was a
wee bit slimy and the hole perhaps not as narrow as I'd like to have to
ensure the plug stays in securely.

What can I do here to fix this up?

An idea was to get some fiberglass resin and put a thin coat in the hole
as to seal things, narrow up the hole width, and strengthen the inner hole
for the plug.

Or perhaps a newer plug would be a big thicker...

btw, the boat is a 70's era 15.5 fiberglass.

I feel that the rest of the transom is fine, just this part around the
hole seems to be a bit questionable.

thanks
Chris

Chris,
The drain plug should not go directly into the aft end. Not only will it
leak, but the water will wick through the plywood and rot it. You need to
buy a 1-inch brass tube and epoxy it into the drain hole. Now the rubber
expansion plug will fit snug.

Here's one.
http://www.outdoorsuperstore.com/sto...=DRAI N+TUBES

You can make your own after a visit to a plumbing supply store. In a pinch,
you could use a piece of PVC, but because of the thickness of the material,
you'd need to enlarge the hole.




"Chris" wrote in message
.. .
hi again,

I've got yet another interesting question which some of you with more
experience can likely say a few words to... I was out testing my project
boat on the trailer, and ensuring the bilge pump would work right by
putting the plug in the boat and filling the back end with a few inches of
water. Well the bilge pump works great, however, when putting the boat
plug in I felt that the wood between the inner and outer fiberglass was a
wee bit slimy and the hole perhaps not as narrow as I'd like to have to
ensure the plug stays in securely.

What can I do here to fix this up?

An idea was to get some fiberglass resin and put a thin coat in the hole
as to seal things, narrow up the hole width, and strengthen the inner hole
for the plug.

Or perhaps a newer plug would be a big thicker...

btw, the boat is a 70's era 15.5 fiberglass.

I feel that the rest of the transom is fine, just this part around the
hole seems to be a bit questionable.

thanks
Chris

Cut away as much as you can to clear away the rot and then glass it
closed using a combination of GRP glass and matt. Now cut a new hole is
a similar position.

A drain plug should not go directly into the aft end. Not only will it
leak, but the water will wick through the plywood and rot it once
again. You need to buy a 1-inch brass tube and epoxy it into the drain
hole. Now the rubber expansion plug will fit snug.

Here's a source:
http://www.outdoorsuperstore.com/sto...=DRAI N+TUBES

You can make your own collar after a visit to a plumbing supply store.
USE BRASS! In a pinch, you could use a piece of PVC, but because of the
thickness of the material, you'd need to enlarge the hole.






wrote:
Chris wrote:
hi again,

I've got yet another interesting question which some of you with more
experience can likely say a few words to... I was out testing my project
boat on the trailer, and ensuring the bilge pump would work right by putting
the plug in the boat and filling the back end with a few inches of water.
Well the bilge pump works great, however, when putting the boat plug in I
felt that the wood between the inner and outer fiberglass was a wee bit
slimy and the hole perhaps not as narrow as I'd like to have to ensure the
plug stays in securely.

What can I do here to fix this up?

An idea was to get some fiberglass resin and put a thin coat in the hole as
to seal things, narrow up the hole width, and strengthen the inner hole for
the plug.

Or perhaps a newer plug would be a big thicker...

btw, the boat is a 70's era 15.5 fiberglass.

I feel that the rest of the transom is fine, just this part around the hole
seems to be a bit questionable.

thanks
Chris

Most boats have a brass or stainless insert that is epoxied into the
hole. It basically looks like a short piece of pipe with one end
beveled out. This may be missing, and would account for the plug being
loose feeling. Also, the plug is usually adjustable, just turn the
lever a couple of turns, try again.

So replacing wood with new plywood means I can cut out a shape of any size
and replace it with a close to equal piece of plywood correct? Just glass
the old plywood to the new plywood, right? No concern over how big a piece
of plywood is, etc? I could use two pieces of plywood for one hole? etc


It appears I've got more rot than I had expected (although the transom feels
strong otherwise).

I've pulled out about a 1 foot x 1 foot section around the drain plug and am
evaluating whether there will be anymore to go too.. Have drilled a bunch of
holes in the lower inner part of the transom to see how far it spreads and
allow all the wood to dry up before my final decision



wrote in message
ups.com...
It's too late to do any more than slightly slow the problem by sealing
the exposed wooden surfaces of the drain hole.

If you like this boat and plan to keep it, you will want to cut the rot
out of the transom. Be sure to go a few inches beyond the point where
you "think" the rot ends when scarfing in the new piece. You should be
able to cut away part of the fiberglass on the outside of the transom
and spoon out the punky wood, cut a new piece of the best marine ply
you can find, and then glass up the exterior again.

This is a great chance to learn from the bad practice of the original
builder. Any hole drilled through a wooden member- transom, stringer,
etc for the purpose of draining water should have the edges sealed up
to prevent water from wicking into the surrounding area and promoting
rot. If it were my project, I would cut the drain hole large enough to
accept a drain plug with a bronze collar fitting. Seal the edges of the
hole with a layer of glass and resin, and then bond the bronze collar
into the sealed hole- perhaps using epoxy.

One rot gets a foothold, it is relentless. Transom rot on small boats
is fairly common, and as most are outboard powered it is double
trouble.

On Thu, 09 Jun 2005 19:17:13 -0400, Chris wrote:

[I have rearranged the order so that it flows chronologically]

wrote in message
ups.com...
It's too late to do any more than slightly slow the problem by sealing
the exposed wooden surfaces of the drain hole.

If you like this boat and plan to keep it, you will want to cut the rot
out of the transom. Be sure to go a few inches beyond the point where
you "think" the rot ends when scarfing in the new piece. You should be
able to cut away part of the fiberglass on the outside of the transom
and spoon out the punky wood, cut a new piece of the best marine ply
you can find, and then glass up the exterior again.

This is a great chance to learn from the bad practice of the original
builder. Any hole drilled through a wooden member- transom, stringer,
etc for the purpose of draining water should have the edges sealed up
to prevent water from wicking into the surrounding area and promoting
rot. If it were my project, I would cut the drain hole large enough to
accept a drain plug with a bronze collar fitting. Seal the edges of the
hole with a layer of glass and resin, and then bond the bronze collar
into the sealed hole- perhaps using epoxy.

One rot gets a foothold, it is relentless. Transom rot on small boats
is fairly common, and as most are outboard powered it is double
trouble.


So replacing wood with new plywood means I can cut out a shape of any
size and replace it with a close to equal piece of plywood correct?
Just glass the old plywood to the new plywood, right? No concern over
how big a piece of plywood is, etc? I could use two pieces of plywood
for one hole? etc


It appears I've got more rot than I had expected (although the transom
feels strong otherwise).

I've pulled out about a 1 foot x 1 foot section around the drain plug
and am evaluating whether there will be anymore to go too.. Have drilled
a bunch of holes in the lower inner part of the transom to see how far
it spreads and allow all the wood to dry up before my final decision




I didn't see the original thread. If it is a fiberglass boat with a
plywood core, then you are probably right. You can probably get away
with putting in a whole bunch of plywood more or less however you want,
But don't leave any voids, and take steps to ensure that the new plywood
is bonded to the adjacent old plywood. You may have to use some kind of
adhesive filler for this. Epoxy, with filler, for example.

On the other hand, if it is a plywood boat with a thin layer of
protective glass, or glass on only the outside, then you are probably
wrong. In that case you will probably need to scarf in the plywood very
carefully.

I'm not an expert, so take my advice with a grain of salt. But the whole
idea behind sandwich construction is that the core experiences mostly
compression loading, and the skin experiences mostly tension.

Of course, this means that you have to do a good job tapering the
fiberglass thickness where you meld old glass with new glass. I think I
have seen a 12:1 ratio recommended. That is, if the glass is 1/8" thick,
you would taper over 1-1/2".

--Mac

One piece is much better. Those joints in the wood have little strength.

"Chris" wrote in message
...
So replacing wood with new plywood means I can cut out a shape of any size
and replace it with a close to equal piece of plywood correct? Just glass
the old plywood to the new plywood, right? No concern over how big a
piece of plywood is, etc? I could use two pieces of plywood for one hole?
etc


It appears I've got more rot than I had expected (although the transom
feels strong otherwise).

I've pulled out about a 1 foot x 1 foot section around the drain plug and
am evaluating whether there will be anymore to go too.. Have drilled a
bunch of holes in the lower inner part of the transom to see how far it
spreads and allow all the wood to dry up before my final decision



wrote in message
ups.com...
It's too late to do any more than slightly slow the problem by sealing
the exposed wooden surfaces of the drain hole.

If you like this boat and plan to keep it, you will want to cut the rot
out of the transom. Be sure to go a few inches beyond the point where
you "think" the rot ends when scarfing in the new piece. You should be
able to cut away part of the fiberglass on the outside of the transom
and spoon out the punky wood, cut a new piece of the best marine ply
you can find, and then glass up the exterior again.

This is a great chance to learn from the bad practice of the original
builder. Any hole drilled through a wooden member- transom, stringer,
etc for the purpose of draining water should have the edges sealed up
to prevent water from wicking into the surrounding area and promoting
rot. If it were my project, I would cut the drain hole large enough to
accept a drain plug with a bronze collar fitting. Seal the edges of the
hole with a layer of glass and resin, and then bond the bronze collar
into the sealed hole- perhaps using epoxy.

One rot gets a foothold, it is relentless. Transom rot on small boats
is fairly common, and as most are outboard powered it is double
trouble.