Fiberglass thickness

laxray

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Jul 11, 2009
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If I am wrapping my new plywood stringer pieces in Fiberglas and poly resin before installing, how thick should I expect this combination to be so that I can lessen the length of my plywood pieces.
 

jigngrub

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Mar 19, 2011
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Re: Fiberglass thickness

Stringers should be installed unwrapped.

Bed/bond stringers to the hull with a suitable adhesive and then layup with resin and glass.
 

laxray

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Re: Fiberglass thickness

I reread WOG's post on stringer building with poly resin Ok so I really only need to put a first coat of resin on my new plywood pieces then bed the piece in fillet them, and finally will have 3 layers over the top. All the top layers will be 1708. If I was going to plan on the tops being a certain height by lessening them the thickness of the top, how thick will 3 layers of 1708 be?

So How thick would 3 layers of 1708 add up to?

Thanks
 

laxray

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Jul 11, 2009
Messages
43
Re: Fiberglass thickness

Stringers should be installed unwrapped.

Bed/bond stringers to the hull with a suitable adhesive and then layup with resin and glass.

Thanks I was posting while you were answering.
 

laxray

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Re: Fiberglass thickness

Other question would be how do you determine the top level of the stringers or do you just get it close then grind down to the height it needs to be?
 

Woodonglass

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Dec 29, 2009
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Re: Fiberglass thickness

Guess-Ti-mate about 1/8 to 3/16 of an inch.;)
You can use 1708 to go over the top but I just use a couple of layers of Torn and Pulled CSM to seal the top edge.
 
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laxray

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Re: Fiberglass thickness

It is amazing these stringers held up as long as they did!@!



The old glass only came up about 3 inches if that!!! I feel like if I do no do this tab insert thing they did at the factory but actually fiberglass the corners I will be much better off in the long run..


 

jigngrub

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Re: Fiberglass thickness

Not a minute too soon on the stringer replacement eh?! Those thing have probably been rotting for a decade or so.

You'll get a better bond if you bed your stringers in raw and unsealed, then after your adhesive has cured out you can start your layups. Brush/roll on your first coat of resin and wait for it to tack up, apply your 1708 and wet it out. Wait for that to tack and hit it with another layer of 1708 and wet it out.

If your resin cures out between layups it'll need to be wiped down with acetone and brushed with resin again before laying more glass.
 
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Woodonglass

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Re: Fiberglass thickness

When using Laminating Resin you can precoat the stringers outside the boat if you wish. they'll stay tacky for a few days and you won't need to wipe em down with acetone to prep em before tabbing as long as you get em installed withing a few days. It's easier to coat em on saw horses in the garage than after they're installed but either way will work. Totally your call;)

You might also consider doing your stringers in this fashion...
 
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bvetter

Petty Officer 1st Class
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Jun 2, 2013
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Re: Fiberglass thickness

I reread WOG's post on stringer building with poly resin Ok so I really only need to put a first coat of resin on my new plywood pieces then bed the piece in fillet them, and finally will have 3 layers over the top. All the top layers will be 1708. If I was going to plan on the tops being a certain height by lessening them the thickness of the top, how thick will 3 layers of 1708 be?

So How thick would 3 layers of 1708 add up to?

Thanks

Give or take, 1/16" of an inch per layer of 1708.
 

laxray

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Re: Fiberglass thickness

If I want to add drain under stringers any other advice.
 

jigngrub

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Re: Fiberglass thickness

Are you going to use floatation foam? If so, what kind?
 

laxray

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Jul 11, 2009
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Re: Fiberglass thickness

I really feel that I have to put some kind of flotation back in if something unfortunate was to happen i would feel awful if i failed to do this. I don't like the pour in. I'd rather use some kind of sheet foam and cut it to fit. That way if there is water in the spaces it can have an opportunity to escape. What are the thoughts on no foam?

Other question on ordering 1708 does it come in different weights and where is the best place to order it from if Im in North Louisiana.
 
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Woodonglass

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Re: Fiberglass thickness

Yup, No foam is like no Insurance.

Uhmmm, 1708 is a specific weight, it means 17 oz cloth and approx. 08 oz of CSM stitched to the back of it. They also make 1808 and 1908.
 

laxray

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Re: Fiberglass thickness

That makes sense. As far as non pour foam, any suggestions?
 

Woodonglass

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Re: Fiberglass thickness

Pour in foam not only adds flotation to the boat but also adds additional structural support to the hull and deck. Using the Blue or Pink Slab foam will stiffen the deck some and add some stiffness to the hull if you cut it to conform fairly well but not as much as the pour in. Like I always say it's your boat and you're free to do as you see fit. I'd prolly plasticized the bottom of the deck and the stringers and the hull and pour the foam. That way if I wanted/needed to remove it in the future it would be an easy process. But Hey, like everybody knows, I'm just an...
 
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