Why glass in all the stringers?

B

Brassie3

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Why do we have to glass in the stingers?
I plan to use 2" marine lumber for stringers and marine plywood as a deck.
I plan on constructing proper drainage paths for all water. The area below the floor will be well ventilated and there should be little rot for years. My boat is a 2003 Cutter 175xle 4.3 mercruiser. The floor and stringers are still under warranty but the owner of Grew got killed in a shoot up with the Police.

Any opinions would be appreciated.
 
tpenfield

tpenfield

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Re: Why glass in all the stringers?

Adds strength . . .

Keeps them from rotting . . .

You don't have to glass them in, it is your choice.
 
RogersJetboat454

RogersJetboat454

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Re: Why glass in all the stringers?

Reason #1
To tie them into the structure of the hull. They're not just there to support the deck, and engine. They also serve to support the hull.

Reason #2
To protect them from water. You anticipate your stringers to have little rot for years. An untreated, properly glassed wood stringer will last decades.
 
H

Home Cookin'

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Re: Why glass in all the stringers?

The informaiton in your post doesn't make sense--why are you rebuilding the boat if it's under warranty?

Anyway, the answer to the question lies in "there should be little rot for years." It would be more satisfactory if there wasn't any rot for the life of the boat. So whil eno method is perfect, you need to do the most you can to prevent rot.

The obvious solution is to start with wood staying dry: seal it in fiberglass; paint it; avoid standing water and have any water contact leave immediately. you suggest this.

The trouble occurs when either the seal (fiberglass or paint) fails, or the water remains on the wood and will inevitably enter.

All wood boats can last for decades, but they need air and care. You have to be able conveniently to remove the deck to paint the bilge. Recreational boats aren't made that way.

Recreational boats are often made from substandard wood on the theory that if they are sealed when they leave the factory, they sell, and it's not a new boat problem when they fail.

Another problem is that boats under 20' have to have positive floatation, which is typically done with foam in the bilge, which typically traps water, defeating the "obvious solution" above. Your plan will solve the water problem but result in a sinking problem.

And avoid bullet holes from gun battles, too.
 
jigngrub

jigngrub

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Re: Why glass in all the stringers?

RogersJetboat454 said:
Reason #1
To tie them into the structure of the hull. They're not just there to support the deck, and engine. They also serve to support the hull.

Reason #2
To protect them from water. You anticipate your stringers to have little rot for years. An untreated, properly glassed wood stringer will last decades.
Click to expand...

This^^^^^

Tabbing (glassing) the stringers to the hull is the fastening method, it's the "nails" that hold the stringer to the hull. The little bit of adhesive between the hull and the bottom of the stringer is there just to hold the stringer in place until they're glassed in.

Boats with wooden stringers are classified as wood reinforced fiberglass construction, fiberglass hulls are pretty floppy without reinforcement of some kind.

The waterproofing of the stringers by the fiberglass and resin is just an added benefit.
 
GA_Boater

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Re: Why glass in all the stringers?

Why glass the stringers? Because your 10 year old Cutter deck and stringers didn't even make ten years from new. If you bought the boat new and took care if it, look what happened. The company was liquidated so it isn't under warranty anymore because it no longer exists. Even if Grew was bought out of bankruptcy the new owners might not honor warranties on prior boats. Here's your chance to do it right.
 
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salty87

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Re: Why glass in all the stringers?

Home Cookin' said:
Another problem is that boats under 20' have to have positive floatation, which is typically done with foam in the bilge, which typically traps water, defeating the "obvious solution" above. Your plan will solve the water problem but result in a sinking problem.
Click to expand...

i don't disagree with most of what you said i do want to point out that the regs requiring flotation foam apply to certification by boatbuilders making boats for sale to the public. or, in the words of the USCG, "The federal safety regulations for recreational vessels with which boatbuilders must comply."

a backyard rebuilder not entering the business of building boats for sale does not fall under these requirements.
 
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Brassie3

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Re: Why glass in all the stringers?

GA_Boater said:
Why glass the stringers? Because your 10 year old Cutter deck and stringers didn't even make ten years from new. If you bought the boat new and took care if it, look what happened. The company was liquidated so it isn't under warranty anymore because it no longer exists. Even if Grew was bought out of bankruptcy the new owners might not honor warranties on prior boats. Here's your chance to do it right.
Click to expand...

It seems to me that the fibreglass serves to seal in the water that will inevitably get in, as it already has.
 
jigngrub

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Re: Why glass in all the stringers?

Brassie3 said:
It seems to me that the fibreglass serves to seal in the water that will inevitably get in, as it already has.
Click to expand...

There's quite a difference between the factory fiberglassing of stringers and the glassing you'll do yourself. They don't worry about doing a good job at the factory because the deck covers it up and no one will ever see it until the deck is removed. You on the other hand will want to do a good job to protect the stringers.

This is how stringers are supposed to be glassed in (courtesy of iboats member Woodonglass):

Stringers_zps840bac88.jpg
 
GA_Boater

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Re: Why glass in all the stringers?

Brassie3 said:
It seems to me that the fibreglass serves to seal in the water that will inevitably get in, as it already has.
Click to expand...

So how did it get in? Do you think if the under deck is well ventilated that alone will stop rot? In the end it's your boat, your money and your investment, so it's your choice.
 
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salty87

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Re: Why glass in all the stringers?

Brassie3 said:
It seems to me that the fibreglass serves to seal in the water that will inevitably get in, as it already has.
Click to expand...

poured flotation foam will do that more than fiberglass.
 
jigngrub

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Re: Why glass in all the stringers?

Brassie3 said:
It seems to me that the fibreglass serves to seal in the water that will inevitably get in, as it already has.
Click to expand...

salty87 said:
poured flotation foam will do that more than fiberglass.
Click to expand...

These things only happen when you neglect your boat and expose it to the elements instead of keeping it covered or garaged when not in use.
 
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salty87

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Re: Why glass in all the stringers?

jigngrub said:
These things only happen when you neglect your boat and expose it to the elements instead of keeping it covered or garaged when not in use.
Click to expand...

proper care always helps but water is very difficult to prevent from keeping where you don't want it to go. moisture is drawn to a dry environment as much as air will do whatever it can to penetrate a vacuum. manufacturers of boats that don't pour flotation foam (read larger boats) incorporate drainage into their designs. not because their design is sloppy but because it's better to plan for the inevitable than to assume they can overcome the effects of moisture over time.
 
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JOz99

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Re: Why glass in all the stringers?

Just curious as to how you could even attach stringers to the hull without fiberglass tabbing?
 
jigngrub

jigngrub

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Re: Why glass in all the stringers?

JOz99 said:
Just curious as to how you could even attach stringers to the hull without fiberglass tabbing?
Click to expand...

Screw through the outside of the hull:laugh::faint2::facepalm:

I think the OP sees the bed of adhesive the stringers are set in to hold them until the tabbing is in and assumes that would be enough... which it most assuredly is not.
 
Yacht Dr.

Yacht Dr.

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Re: Why glass in all the stringers?

Its called Structure .. Energy transfer .. making your boat safe to use kinda thing when you think its cool to push that go lever down and have everyone on the vessel survive the duration of motion on water without killing anyone.

K.

YD.
 
B

Brassie3

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Re: Why glass in all the stringers?

Home Cookin' said:
The informaiton in your post doesn't make sense--why are you rebuilding the boat if it's under warranty?

Anyway, the answer to the question lies in "there should be little rot for years." It would be more satisfactory if there wasn't any rot for the life of the boat. So whil eno method is perfect, you need to do the most you can to prevent rot.

The obvious solution is to start with wood staying dry: seal it in fiberglass; paint it; avoid standing water and have any water contact leave immediately. you suggest this.

The trouble occurs when either the seal (fiberglass or paint) fails, or the water remains on the wood and will inevitably enter.

All wood boats can last for decades, but they need air and care. You have to be able conveniently to remove the deck to paint the bilge. Recreational boats aren't made that way.

Recreational boats are often made from substandard wood on the theory that if they are sealed when they leave the factory, they sell, and it's not a new boat problem when they fail.

Another problem is that boats under 20' have to have positive floatation, which is typically done with foam in the bilge, which typically traps water, defeating the "obvious solution" above. Your plan will solve the water problem but result in a sinking problem.

And avoid bullet holes from gun battles, too.
Click to expand...

There are other dry locations to place foam. The foam that is there is likely doesn't float nor is it buoyant I believe that the wider stringers along with additional cross members will distribute the loads amply. The accident that takes this boat to the bottom will likely be in shallow water, and, also be a write off, save for the sterndrive. I should have a buoy tethered to it just in case. The Bay of Quinte is the deepest place this boat is going. After the refurbishment we may rechristen her "Sunnyvale 1". Thanks for your help...
 
B

Brassie3

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Re: Why glass in all the stringers?

Since a lot of the boats out there are already rotted (rotting). They are all out there pounding the waves unbeknownst to their driver. I believe a structure of 2" wide stringers, multiple cross members, and a deck all tied together and 3m 5200'd to the hull will be more than adequate. Correct me if I'm wrong
 
tpenfield

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Re: Why glass in all the stringers?

Brassie3 said:
Since a lot of the boats out there are already rotted (rotting). They are all out there pounding the waves unbeknownst to their driver. I believe a structure of 2" wide stringers, multiple cross members, and a deck all tied together and 3m 5200'd to the hull will be more than adequate. Correct me if I'm wrong
Click to expand...

It is really hard to say . . . but, you'll be the first to know.
 
RogersJetboat454

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Re: Why glass in all the stringers?

Brassie3 said:
Since a lot of the boats out there are already rotted (rotting). They are all out there pounding the waves unbeknownst to their driver. I believe a structure of 2" wide stringers, multiple cross members, and a deck all tied together and 3m 5200'd to the hull will be more than adequate. Correct me if I'm wrong
Click to expand...

There's lots of houses still standing with rotten sills. If you were going to rebuild a house with a rotten sill, would you leave the sills out, and justify it because of the other houses still standing with rotten sills?

Cruise around long enough here, and you will find pictures of cracked hulls and transoms due to the structure failing from rot. The rotted boats "out there pounding the waves" may not have problems.... YET. It's only a matter of time.

You are being told the correct way to rebuild your boat. Some of the responders to your post are professionals who do this day in, and day out. They understand all the forces at play, and how to properly build a boat so it is both; A. Strong enough to handle getting pounded. AND B. Watertight, so that the structure does not rot.

The fiberglass hull of your boat does not have enough rigidity to SAFELY stay together with out PROPER reinforcement. Without reinforcement, the fiberglass will flex, and start to crack. Cracks can be minor surface cracks in the gel coat, or the big unexpected gash that opens up.

But hey... it's your boat, build it any way you like....
 
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