I have a 1969 fiberglass (polyester) hulled houseboat. It's a Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers are
shot. Everything I have read so far basicly says to epoxy the stringers in,
fillet and glass over. I am certain the first two steps were omitted, either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From what
I can see, water leaked in at the bow (and other places) and simply migrated
to the back of the boat. The rot is really bad starting in the bildge (the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was done
back then?

Now I'm not so sure that I should put the new stringers in using the current
methods. For example, will the vibration from the motors cause cracking in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve

I think that the methods are pretty much the same. If your boat
relied on the strength of the stringer material to keep it from flexing
then the rot may be part of why the stringers are no longer on the
hull. It also could just be a bad layup. You need to really support
the hull well while you fabricate and install new stringers.

Some builders anticipated the stringer material rotting and put enough
fiberglass on the stringers so that the fiberglass would be strong
enough even after the wood rotted. Today some builders are using
composites as stringers. No wood. I have seen fiberglass sheet used
alone.

anxious boater wrote:
I have a 1969 fiberglass (polyester) hulled houseboat. It's a Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers are
shot. Everything I have read so far basicly says to epoxy the stringers in,
fillet and glass over. I am certain the first two steps were omitted, either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From what
I can see, water leaked in at the bow (and other places) and simply migrated
to the back of the boat. The rot is really bad starting in the bildge (the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was done
back then?

Now I'm not so sure that I should put the new stringers in using the current
methods. For example, will the vibration from the motors cause cracking in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve

anxious boater wrote:
I have a 1969 fiberglass (polyester) hulled houseboat. It's a Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers are
shot. Everything I have read so far basicly says to epoxy the stringers in,
fillet and glass over. I am certain the first two steps were omitted, either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From what
I can see, water leaked in at the bow (and other places) and simply migrated
to the back of the boat. The rot is really bad starting in the bildge (the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was done
back then?

Now I'm not so sure that I should put the new stringers in using the current
methods. For example, will the vibration from the motors cause cracking in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve


Back in 1969, a common boat bulding philosophy was to depend on wood
for strength and then to "protect" the wood by encapsulating it in
fiberglass. Remember, there were still a lot of brand new wooden boats
built in the late 60's. A look at your stringer would help determine a
lot about the builder's original intent. If when sawing into the
stringer your're finding a great big chunk of wood covered by only a
couple of layers of glass cloth, (which it sounds like you are, from
the description), the builder considered the wood itself the structural
component. In later years, the role of wood in stringers began to
change. The wood was reduced in size and used somewhat more as a form
around which to laminate
a stringer. In cases where there is a smaller piece of wood the builder
was relying more on the strength of the laminate than the core. A lot
of modern boats are bulit with hollow stringers (like a box beam) or
use foam instead of wood for the core, and all the strength of the
stringer is in the laminate and it's shape.

You should get a highly qualified marine surveyor and maybe a naval
architect to look at your specific situation. Sometimes there is a cure
available by building up an extra few inches of thickness on your
existing laminate to "take up the slack" from the rotting core and
restore adequate strength. Othertimes, not.

I suspect that with a 1969 boat you will need to yank out the current
stringers entirely. If the rot appears localized, you will certainly
want to take out a couple of feet of material beyond the point where
you think the rot ends. Drilling small pilot holes into the stringers
and examining the drill scavagings will let you know about places where
the wood is wet or soft, and you can use a moisture meter to good
advantage in your situation.

As far as replacement or repair technique, most likely you are going to
be restricted to redoing something close to the original build. There
would be no point in even attempting to "build up" existing stringers
with additional layers of material if the stringers are no longer
attached to the hull.

Here's hoping you like this boat a lot. What you're about is no small
undertaking.

comments throughout

wrote in message
oups.com...

anxious boater wrote:
I have a 1969 fiberglass (polyester) hulled houseboat. It's a Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers are
shot. Everything I have read so far basicly says to epoxy the stringers
in,
fillet and glass over. I am certain the first two steps were omitted,
either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From
what
I can see, water leaked in at the bow (and other places) and simply
migrated
to the back of the boat. The rot is really bad starting in the bildge
(the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was
done
back then?

Now I'm not so sure that I should put the new stringers in using the
current
methods. For example, will the vibration from the motors cause cracking
in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve


Back in 1969, a common boat bulding philosophy was to depend on wood
for strength and then to "protect" the wood by encapsulating it in
fiberglass. Remember, there were still a lot of brand new wooden boats
built in the late 60's. A look at your stringer would help determine a
lot about the builder's original intent. If when sawing into the
stringer your're finding a great big chunk of wood covered by only a
couple of layers of glass cloth, (which it sounds like you are, from
the description), the builder considered the wood itself the structural

that is the case here. Lots of wood, some glass cloth.

component. In later years, the role of wood in stringers began to
change. The wood was reduced in size and used somewhat more as a form
around which to laminate
a stringer. In cases where there is a smaller piece of wood the builder
was relying more on the strength of the laminate than the core. A lot
of modern boats are bulit with hollow stringers (like a box beam) or
use foam instead of wood for the core, and all the strength of the
stringer is in the laminate and it's shape.

You should get a highly qualified marine surveyor and maybe a naval
architect to look at your specific situation. Sometimes there is a cure
available by building up an extra few inches of thickness on your
existing laminate to "take up the slack" from the rotting core and
restore adequate strength. Othertimes, not.

I have had a couple of surveyors opinions. They only saw the stringers from
access holes I cut but they seemed to think that replacing or adding more
cloth were the options, replacing being the prefrerred. That's my take
anyway. I was never told to abandon ship and as I am doing the work myself,
I can afford the materials.


I suspect that with a 1969 boat you will need to yank out the current
stringers entirely. If the rot appears localized, you will certainly
want to take out a couple of feet of material beyond the point where
you think the rot ends. Drilling small pilot holes into the stringers
and examining the drill scavagings will let you know about places where
the wood is wet or soft, and you can use a moisture meter to good
advantage in your situation.

I have cut all but one stringer right out. The wood is still mostly solid in
that one, but it doesn't touch the hull. I'll probably toss it as well.


As far as replacement or repair technique, most likely you are going to
be restricted to redoing something close to the original build. There
would be no point in even attempting to "build up" existing stringers
with additional layers of material if the stringers are no longer
attached to the hull.

Here's hoping you like this boat a lot. What you're about is no small
undertaking.


So far I have enjoyed researching and reading up on boat repair and doing
the work. Is the boat worth this much work. Probably not but the
satisfaction of completeing such an undertaking ...

Hi Steve,

I have a 1972 boat that had the same problem I spent the greater part
of last summer fixing. I read everything I could find to read about it
and then decided to do the job myself. It turned out great and I think
the boat is stronger and lighter than original.

I agreed to paint my dad's house (a bigger job than anticipated) in
exchange for the "family boat" that dad no longer used (but it was
stored in 'dry' storage.) After making my dad's house beautiful, I went
to load up the boat and stepping onto the deck I went right through. It
was rotted through and through. I then realized the deal I made with
dad wasn't such a great deal- well maybe for my dad it was, and that's
OK I guess.

Anyway I brought the boat home and went about stripping the boat down
(removing all interior upholstery and hardware) removing the deck and
stringers. I cut everything down to the bare hull and made sure to kill
any sign of mildew or mold (didn't want it growing under anything...)
Fortunately for me, the transom was OK - there were a couple of tiny
rot spots in it I was able to repair.

Now that I had a completely clean hull, I laid out stringers out of
Alaska Yellow Cedar (not for strength, but because it doesn't rot)
fitting them closely to the hull line. I made up cross-braces out of
marine-grade plywood. Before placing ANY wood in the boat, I first
coated it in thin epoxy that soaked into the wood (sometimes two coats
if it looked like it needed it) which didn't increase the weight of the
wood by much. This way I knew the wood was totally encapsulated. Then I
placed the wood into the boat, laid everything out and screwed/glued
the cross braces to the main stringers with cleats (also pre-treated.)
I also added supports for the deck (places to attach the deck and seats
down to the stringers/cross-braces.)

Once everything was in place I started lay up. I used a coarse
fiberglass mat (I used as large pieces of fiberglass mat as possible -
eliminating as many joints and overlaps as possible) for the first
layer. I did NOT use polyester resin, instead I used epoxy for the
entire job. This takes a little longer since I think it's important to
allow the epoxy to cure between coats which can take a week. After my
first layup, then I used a finer cloth over the heavy cloth, making
sure the joints and overlaps in this cloth were in different places
than the first layup. Again, I used epoxy and at this time I also
coated the entire inside of the hull. (One thing to make sure of before
you start this is to support the boat hull in such a way so that it's
not deformed [even a little] because however the hull is shaped when
you start, is how it will be shaped forever.)

After a lot of work and a couple gallons of epoxy, it came out
beautifully and the boat actually works better than ever. I think it's
a little stiffer and it definitely feels more solid
than before (that is, before it rotted out.) From what I removed from
the boat I could tell it was not put together very well... there was no
glass mat, only chopper material covering the stringers which is why I
think it failed. The thickness of the chopped glass varied a lot.

That's my story...


Jeff





anxious boater wrote:
I have a 1969 fiberglass (polyester) hulled houseboat. It's a Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers are
shot. Everything I have read so far basically says to epoxy the stringers in,
fillet and glass over. I am certain the first two steps were omitted, either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From what
I can see, water leaked in at the bow (and other places) and simply migrated
to the back of the boat. The rot is really bad starting in the bilge (the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was done
back then?

Now I'm not so sure that I should put the new stringers in using the current
methods. For example, will the vibration from the motors cause cracking in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve

Hi Jeff,

You sometimes don't know what you're getting into. Some advice I read and
didn't head - "If you find yourself in a hole, STOP DIGGING!"

Because of the stringers I also ended up pretty much gutting the boat. At
least I can now build something I'll be happy with.

A surveyor I talked to suggested that I epoxy the enitre hull while I was
doing everything else. You did that. I never asked him why I should. Why did
you go that route?

"Chehalis Jeff" wrote in message
oups.com...
Hi Steve,

I have a 1972 boat that had the same problem I spent the greater part
of last summer fixing. I read everything I could find to read about it
and then decided to do the job myself. It turned out great and I think
the boat is stronger and lighter than original.

I agreed to paint my dad's house (a bigger job than anticipated) in
exchange for the "family boat" that dad no longer used (but it was
stored in 'dry' storage.) After making my dad's house beautiful, I went
to load up the boat and stepping onto the deck I went right through. It
was rotted through and through. I then realized the deal I made with
dad wasn't such a great deal- well maybe for my dad it was, and that's
OK I guess.

Anyway I brought the boat home and went about stripping the boat down
(removing all interior upholstery and hardware) removing the deck and
stringers. I cut everything down to the bare hull and made sure to kill
any sign of mildew or mold (didn't want it growing under anything...)
Fortunately for me, the transom was OK - there were a couple of tiny
rot spots in it I was able to repair.

Now that I had a completely clean hull, I laid out stringers out of
Alaska Yellow Cedar (not for strength, but because it doesn't rot)
fitting them closely to the hull line. I made up cross-braces out of
marine-grade plywood. Before placing ANY wood in the boat, I first
coated it in thin epoxy that soaked into the wood (sometimes two coats
if it looked like it needed it) which didn't increase the weight of the
wood by much. This way I knew the wood was totally encapsulated. Then I
placed the wood into the boat, laid everything out and screwed/glued
the cross braces to the main stringers with cleats (also pre-treated.)
I also added supports for the deck (places to attach the deck and seats
down to the stringers/cross-braces.)

Once everything was in place I started lay up. I used a coarse
fiberglass mat (I used as large pieces of fiberglass mat as possible -
eliminating as many joints and overlaps as possible) for the first
layer. I did NOT use polyester resin, instead I used epoxy for the
entire job. This takes a little longer since I think it's important to
allow the epoxy to cure between coats which can take a week. After my
first layup, then I used a finer cloth over the heavy cloth, making
sure the joints and overlaps in this cloth were in different places
than the first layup. Again, I used epoxy and at this time I also
coated the entire inside of the hull. (One thing to make sure of before
you start this is to support the boat hull in such a way so that it's
not deformed [even a little] because however the hull is shaped when
you start, is how it will be shaped forever.)

After a lot of work and a couple gallons of epoxy, it came out
beautifully and the boat actually works better than ever. I think it's
a little stiffer and it definitely feels more solid
than before (that is, before it rotted out.) From what I removed from
the boat I could tell it was not put together very well... there was no
glass mat, only chopper material covering the stringers which is why I
think it failed. The thickness of the chopped glass varied a lot.

That's my story...


Jeff





anxious boater wrote:
I have a 1969 fiberglass (polyester) hulled houseboat. It's a Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers are
shot. Everything I have read so far basically says to epoxy the stringers
in,
fillet and glass over. I am certain the first two steps were omitted,
either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From
what
I can see, water leaked in at the bow (and other places) and simply
migrated
to the back of the boat. The rot is really bad starting in the bilge (the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was
done
back then?

Now I'm not so sure that I should put the new stringers in using the
current
methods. For example, will the vibration from the motors cause cracking
in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve

Polyster resin is not really very water proof. Water permeates it over
time. Epoxy is more water resistant. Epoxy is also less brittle than
polyster resin. So it less likely to crack when flexed. It is also
generally stronger. You use it the same as polyster resin. The mix is just
different, usually 1:1, 2:1 or 3:1 hardner. I personally like US Composites
http://www.uscomposites.com/ epoxies and they are very reasonably priced.
Big chemical companies make the epoxy ingredients and smaller companies
package and sell it so you're just paying for the name when you buy
something like West Systems. You can get a thin coat epoxy and paint the
inside of the hull. You can also seal your lumber with thin epoxy before
you start installing it. Make sure you really soak the ends well. You use
epoxy with fiberglass cloth just like you would polyster resin.

"anxious boater" wrote in message
.. .
Hi Jeff,

You sometimes don't know what you're getting into. Some advice I read and
didn't head - "If you find yourself in a hole, STOP DIGGING!"

Because of the stringers I also ended up pretty much gutting the boat. At
least I can now build something I'll be happy with.

A surveyor I talked to suggested that I epoxy the enitre hull while I was
doing everything else. You did that. I never asked him why I should. Why
did you go that route?

"Chehalis Jeff" wrote in message
oups.com...
Hi Steve,

I have a 1972 boat that had the same problem I spent the greater part
of last summer fixing. I read everything I could find to read about it
and then decided to do the job myself. It turned out great and I think
the boat is stronger and lighter than original.

I agreed to paint my dad's house (a bigger job than anticipated) in
exchange for the "family boat" that dad no longer used (but it was
stored in 'dry' storage.) After making my dad's house beautiful, I went
to load up the boat and stepping onto the deck I went right through. It
was rotted through and through. I then realized the deal I made with
dad wasn't such a great deal- well maybe for my dad it was, and that's
OK I guess.

Anyway I brought the boat home and went about stripping the boat down
(removing all interior upholstery and hardware) removing the deck and
stringers. I cut everything down to the bare hull and made sure to kill
any sign of mildew or mold (didn't want it growing under anything...)
Fortunately for me, the transom was OK - there were a couple of tiny
rot spots in it I was able to repair.

Now that I had a completely clean hull, I laid out stringers out of
Alaska Yellow Cedar (not for strength, but because it doesn't rot)
fitting them closely to the hull line. I made up cross-braces out of
marine-grade plywood. Before placing ANY wood in the boat, I first
coated it in thin epoxy that soaked into the wood (sometimes two coats
if it looked like it needed it) which didn't increase the weight of the
wood by much. This way I knew the wood was totally encapsulated. Then I
placed the wood into the boat, laid everything out and screwed/glued
the cross braces to the main stringers with cleats (also pre-treated.)
I also added supports for the deck (places to attach the deck and seats
down to the stringers/cross-braces.)

Once everything was in place I started lay up. I used a coarse
fiberglass mat (I used as large pieces of fiberglass mat as possible -
eliminating as many joints and overlaps as possible) for the first
layer. I did NOT use polyester resin, instead I used epoxy for the
entire job. This takes a little longer since I think it's important to
allow the epoxy to cure between coats which can take a week. After my
first layup, then I used a finer cloth over the heavy cloth, making
sure the joints and overlaps in this cloth were in different places
than the first layup. Again, I used epoxy and at this time I also
coated the entire inside of the hull. (One thing to make sure of before
you start this is to support the boat hull in such a way so that it's
not deformed [even a little] because however the hull is shaped when
you start, is how it will be shaped forever.)

After a lot of work and a couple gallons of epoxy, it came out
beautifully and the boat actually works better than ever. I think it's
a little stiffer and it definitely feels more solid
than before (that is, before it rotted out.) From what I removed from
the boat I could tell it was not put together very well... there was no
glass mat, only chopper material covering the stringers which is why I
think it failed. The thickness of the chopped glass varied a lot.

That's my story...


Jeff





anxious boater wrote:
I have a 1969 fiberglass (polyester) hulled houseboat. It's a
Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers
are
shot. Everything I have read so far basically says to epoxy the
stringers in,
fillet and glass over. I am certain the first two steps were omitted,
either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From
what
I can see, water leaked in at the bow (and other places) and simply
migrated
to the back of the boat. The rot is really bad starting in the bilge
(the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was
done
back then?

Now I'm not so sure that I should put the new stringers in using the
current
methods. For example, will the vibration from the motors cause cracking
in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve

James is right. Epoxy is more flexible, water-proof (as he says, poly
resin is NOT) and stronger by weight.

I wouldn't be so quick to assume the stringers are only there to
support the deck. When I removed my stringers (yes it was quite a job,
but well worth it) they were essentially mush, so they provided little
support as is. When I replaced them (as I think I said I sealed
[soaked] them with thin epoxy first) and 'glassed' them in with
fiberglass roving I could tell the whole boat was a LOT stiffer,
completely different. I am a big guy and when I walked around inside
the hull, I could feel it flex, so I put boards (planks) down I could
walk on so I didn't maybe go through a thin spot on the hull bottom.
After putting in the stringers (no deck yet,) it just felt a whole lot
different.

I used USComposites Epoxy and was VERY pleased with it. I found it to
be the least expensive. I bought both Thin and Thick (thin for sealing
wood and thick for fiberglass layup) epoxy. I also bought high-density
flotation 'expanding foam' (comes in two-part liquid form) to pour
in-between the stringers. The Coast guard requires a specific amount of
flotation in boats so I did the math and poured the correct amount in.
Again, it worked great.

After putting the deck on (I epoxied the entire deck on ALL sides first
- two coats, sanded between coats) then the boat felt even stiffer. I
can tell you FOR SURE that the boat performs a lot better than it ever
did in rough water. It's a modified tri-hull and the rigidity seems to
allow the boat to keep going over the waves instead of soaking up the
impact and slowing. It's difficult to describe, but it's a noticeable
difference like putting more air in an inflatable boat.

I hinted about this in my last post, but BE SURE to calculate where the
seats and any other stress points will be in the boat BEFORE you put
the deck on. You can build this into the stringers/cross braces so
stress is transferred properly across the bottom of the boat. Also,
epoxy or glue and screw your deck down to the tops of the stringers. I
pre-drilled all the holes for the screws and dropped a little epoxy in
each hole before screwing the screw in. I don't want to give the water
ANY place to enter the stringers again.

Also keep in mind that you can put epoxy over properly prepared
polyester resin, but you CANNOT put poly resin over epoxy. Well you
can, but it won't stick very well and it will eventually fail, so don't
waste your time. It easier and better to only use epoxy.

I am considering building a little website covering the whole process I
went through with photos, etc. I sure wish I could've known everything
I know now before I started.

Jeff





anxious boater wrote:
Hi Jeff,

You sometimes don't know what you're getting into. Some advice I read and
didn't head - "If you find yourself in a hole, STOP DIGGING!"

Because of the stringers I also ended up pretty much gutting the boat. At
least I can now build something I'll be happy with.

A surveyor I talked to suggested that I epoxy the entire hull while I was
doing everything else. You did that. I never asked him why I should. Why did
you go that route?

"Chehalis Jeff" wrote in message
oups.com...
Hi Steve,

I have a 1972 boat that had the same problem I spent the greater part
of last summer fixing. I read everything I could find to read about it
and then decided to do the job myself. It turned out great and I think
the boat is stronger and lighter than original.

I agreed to paint my dad's house (a bigger job than anticipated) in
exchange for the "family boat" that dad no longer used (but it was
stored in 'dry' storage.) After making my dad's house beautiful, I went
to load up the boat and stepping onto the deck I went right through. It
was rotted through and through. I then realized the deal I made with
dad wasn't such a great deal- well maybe for my dad it was, and that's
OK I guess.

Anyway I brought the boat home and went about stripping the boat down
(removing all interior upholstery and hardware) removing the deck and
stringers. I cut everything down to the bare hull and made sure to kill
any sign of mildew or mold (didn't want it growing under anything...)
Fortunately for me, the transom was OK - there were a couple of tiny
rot spots in it I was able to repair.

Now that I had a completely clean hull, I laid out stringers out of
Alaska Yellow Cedar (not for strength, but because it doesn't rot)
fitting them closely to the hull line. I made up cross-braces out of
marine-grade plywood. Before placing ANY wood in the boat, I first
coated it in thin epoxy that soaked into the wood (sometimes two coats
if it looked like it needed it) which didn't increase the weight of the
wood by much. This way I knew the wood was totally encapsulated. Then I
placed the wood into the boat, laid everything out and screwed/glued
the cross braces to the main stringers with cleats (also pre-treated.)
I also added supports for the deck (places to attach the deck and seats
down to the stringers/cross-braces.)

Once everything was in place I started lay up. I used a coarse
fiberglass mat (I used as large pieces of fiberglass mat as possible -
eliminating as many joints and overlaps as possible) for the first
layer. I did NOT use polyester resin, instead I used epoxy for the
entire job. This takes a little longer since I think it's important to
allow the epoxy to cure between coats which can take a week. After my
first layup, then I used a finer cloth over the heavy cloth, making
sure the joints and overlaps in this cloth were in different places
than the first layup. Again, I used epoxy and at this time I also
coated the entire inside of the hull. (One thing to make sure of before
you start this is to support the boat hull in such a way so that it's
not deformed [even a little] because however the hull is shaped when
you start, is how it will be shaped forever.)

After a lot of work and a couple gallons of epoxy, it came out
beautifully and the boat actually works better than ever. I think it's
a little stiffer and it definitely feels more solid
than before (that is, before it rotted out.) From what I removed from
the boat I could tell it was not put together very well... there was no
glass mat, only chopper material covering the stringers which is why I
think it failed. The thickness of the chopped glass varied a lot.

That's my story...


Jeff





anxious boater wrote:
I have a 1969 fiberglass (polyester) hulled houseboat. It's a Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers are
shot. Everything I have read so far basically says to epoxy the stringers
in,
fillet and glass over. I am certain the first two steps were omitted,
either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From
what
I can see, water leaked in at the bow (and other places) and simply
migrated
to the back of the boat. The rot is really bad starting in the bilge (the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was
done
back then?

Now I'm not so sure that I should put the new stringers in using the
current
methods. For example, will the vibration from the motors cause cracking
in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve

Thanks for the responses so far!

I have cut the stringers out in the main cabin. I really can't see how they
provided any strength. On one main stringer (they are 16" high) the glass
cloth was buldging out a good 1 1/2" on each side! As I mentioned before,
another one is a good 1/2" off the hull. On top of that there was a gap of
about 1/8" between cloth and wood at the top, along the whole length of each
one. It looks like the wood actually shrunk! Is that possible? I took a
piece of the stringer wood into a wood shop and they weren't specific other
than it is pine of some kind (very clear and light). I believe these boats
were made in Florida.

I'm not sure of the weight of cloth on the stringer, it's more like a
roving, but there are two rather thin layers.

I'm beginning to think these stringer are there to support the floor, and
that's it.


"anxious boater" wrote in message
.. .
I have a 1969 fiberglass (polyester) hulled houseboat. It's a Thunderbird
Drift-R-Cruise. All the engine stringers and three interior stringers are
shot. Everything I have read so far basicly says to epoxy the stringers
in,
fillet and glass over. I am certain the first two steps were omitted,
either
when this boat was built or this job was done in the past. Some of the
inside stringers aren't even resting on the hull interior surface. From
what
I can see, water leaked in at the bow (and other places) and simply
migrated
to the back of the boat. The rot is really bad starting in the bildge (the
stringers oozed out when I started cutting!) and improves some moving up
closer to the bow. Is this poor boat building, or just the way it was done
back then?

Now I'm not so sure that I should put the new stringers in using the
current
methods. For example, will the vibration from the motors cause cracking in
the hull glass if they are epoxied in, solid as a rock?

Thanks,
Steve