# How much glass is in a roll

Discussion in 'Fiberglass and Composite Boat Building' started by brokensheer, Jan 22, 2012.

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### brokensheerSenior Member

I know there aRE VARIABLES but for example in a roll of 1708 50" wide how much glass by square foot is in that roll?

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### lewisboatsObsessed Member

according to here: http://www.shopmaninc.com/cloth.html
the length of a roll is generally 125 yards but can vary from 110-130. You are looking at around 1575 sq ft for a roll. Or are you talking weight? If so you need to divide into yardage and multiply by the oz per yard cloth weight.

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### gonzoSenior Member

Remember that it is 17oz per sq.yd and .75oz per sq.ft.

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### RolySenior Member

So weigh it & do the math if it isn't a virgin roll. Allowing for core.

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Thanks

6. ### FrostyPrevious Member

I bought a kilo of glass the other day, he said it is 300 I dont know what that is but he said it will have about 4.5 sq meter, it is very thin, I was a bit dissapointed how thin actually but at least I can work it which is what I need to do.

So does it not depend on the weight of the glass as to how much you get in a roll.

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### RolySenior Member

Woven cloth I presuime.
1000/4.5= 222gm/m2
222/28.4=7.8oz/m2 which is about 6oz/yd2 which is ok for surfboards or skinning your dingy.

8. ### FrostyPrevious Member

Chopped strand mat,--Is that what 300 means --300 grams per SQ meter or 300 miligrams. It is very thin --ive never seen thinner, you can see through it.

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### RolySenior Member

If aint woven or stitched together with threads as in DB,triax,uni, & it looks like csm as in
random stuck together stands then its csm. I 've never heard 300 for a name.
And csm comes in oz/sqft. I only ever used it on house roofs.

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