Fiberglass weight

Wallman67

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Jun 2, 2009
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Local shop in town sells 6 oz mat which I purchased 10 yards of with 15 gallons of expoxy. I can special order 10 oz mat from the dealer but no body in town stocks or can get heavier mat. Been reading forums on iboats and alot of builders use 1708 which is 17 oz.

So here's my question.....Can I use my 6 oz mat for stringers and glassing in my transom just using more layers ? Should I order 10 oz ? I guess what I'm asking is how many oz of fiberglass should be used to cover the stringers , deck and transom ? The boat shop said first layer waterprof's the wood and every other layer is for strenght. He said 2-3 layers more of 6 oz would be fine for the stringers strenght. Along the same line he said 6-8 layers holding the transom to the outer skin would also be enough.

What are your thoughts ?
 

Bondo

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Re: Fiberglass weight

Local shop in town sells 6 oz mat which I purchased 10 yards of with 15 gallons of expoxy.
What are your thoughts ?

Ayuh,... I use cloth with epoxy,... Mat is for Poly....

Cloth is Strength, mat is for bulk...
 

Wallman67

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Re: Fiberglass weight

I stand corrected.....I did purchase 6 oz cloth, not mat for the job to use with the expoxy.:redface:
 

oops!

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Re: Fiberglass weight

the 6 oz cloth you purchased is more than likely a finishing cloth......it has very little structural stregnth.

i highly suggest that you purchase some roving or better yet ...the bi ax material.

what you are looking for in the glass on the transom is anti crush. as well as stregnth from the tabbing to the hull....the thin 6 oz will do little for either no matter how many layers you use.
 

Wallman67

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Re: Fiberglass weight

Ok thanks OOP's, After more research and talking to the local boat shop, he mainly sell materials for building wooden boat kits, canoes, and kayaks, he sold me some 17 oz woven roving. He didn't have 1708 biaxle, but did have some 4 inch 1708 biaxle tape which I also purchased. Both will be used with my epoxy resin. Between these two I will do the transom and stringers.

The 6 oz woven cloth I purchased is cloth used for cedar strip canoes and fiberglass hull repairs. I'm guessing minor repairs at that, even know he's convinced that the 6 oz cloth would do everything my boat needs. Is there a way I can use some of this up in my restore, say 2-3 layers with the 17 oz on any of the deck, transom, or stringers ? This would make the 17 oz go further.

I also used some of the 6 oz woven cloth for a below waterline hole repair on the inside, 6 layers. I haven't done the outside repair yet, I'm thinking of using the 17 0z on the outide for strength.
 

oops!

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Re: Fiberglass weight

ok.........the ONLY PURPOSE for the 6 oz cloth is to make a surface smooth to apply paint or gellcoat with little fairing.....it has VERY LITTLE STRUCTURAL PROPERTYS.

he is wrong by saying that you could wrap your stringers and transom in it and it will be fine....even with epoxy.

but its great that he had some 17 oz stuff for you...especially with out the matt backing as you are using epoxy.

you can use your big 17 oz cloth for the out side repair.....but remember it will be very thick....and you will have a bump on the outside of your boat.

i dont know what type of repair you are doing on the out side...but if you do use the 17 ox fabric...dish out the existing glass so you wont have that bump.
the 17 oz will also net be a flat surface to paint...so here is where some of your 6 oz will be perfect just lay it over top of the 17 oz material with your epoxy....and paint or other.

im glad he had some other material for you to use....if you can post pics it will really help us with what type of repair to do.

cheers
oops
 

oops!

Supreme Mariner
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Re: Fiberglass weight

lol.....just saw where you are...dont know if you are south or central...but i hope you have a warm place to work in..
if you are in edmonchuck.......kick you mayor in the butt and tell him to build our hockey team a new rink.....if they leave edmonton there will be riots !
 

Wallman67

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Jun 2, 2009
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Re: Fiberglass weight

:D....Big Oiler fan, grew up in Camrose, just outside Edmonton. Son's hockey coach is the goalie's brother , Dubnyk,....small world.

Here is a pic of the two holes...glassed with 6 oz woven on the inside. Each hole is about 2 inches by 6-8 inches in lenght. Made by my circular saw..:rolleyes:

http://i936.photobucket.com/albums/ad202/Wallman1967/IMG00023-20101127-1218.jpg

http://i936.photobucket.com/albums/ad202/Wallman1967/IMG00024-20101127-1218-Copy.jpg

You can see the white traced by the black marker is the hole.

What I did is feather out inside and outside to a 12 to 1 ratio. Put release paper on outside. Put 3 layers cut to hole inside hole, and 3 more layers over hole going bigger each time by 2 inches. Think this inside repair would be good if I used the 17 oz , but I didn't. I haven't done the outside yet.

Should I re-sand and bevel out the repair on the inside and re-lay the glass repair using 17 oz woven roving ? Or can I just go over the repair job with a single layer of 17 oz on the inside and do outside repair with a couple of 17 oz cut to hole size, a couple slightly larger and the last one being 6 oz.

I guess a bump isn't that bad , being on the bottom, most won't see it.
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: Fiberglass weight

yeah...one 17 wrap on the inside over the other stuff.....epoxy is really good glue....so the repair will hold.

if you feather the outside....the bump wont be as bad
 

drewpster

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Re: Fiberglass weight

Canadians! geesh :rolleyes::p
I played air hockey once. LOL no offense kids.
 
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