Confused on Mats, cloths etc

Bull54

Petty Officer 3rd Class
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Jul 15, 2008
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85
I think I have read just about every post on this stuff I can find on the forum, but I am still confused on how to determine what size cloth or mat I should use in what situations. Is there anywhere either here or elsewhere that would have access to that would kind of give me a chart or reference for this?

I know for you old salts this is easy stuff but for us rookies, it can and is confusing when you throw in all the different kinds of cloth, mats, epoxies, polys, etc. Just about when I "think" I have it all figured out I read more and then I am confused again so any help trying to sort this stuff out in LAYMAN terms would be greatly appreciated.:)
 

oops!

Supreme Mariner
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Oct 18, 2007
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Re: Confused on Mats, cloths etc

the manufacturers will all give you "lay up schedules" and will tell you the weights to use on any given area and function.

there are several types of glass.....s class e class and so on.
for laymans purposes....ill just describe the basics


CSM......matt.......chopped strand matt.....this is the work horse of fiberglass. uasually coming in 3 main weights....3/4 oz, 1 oz and 1.5 oz

it looks like a bunch of hairs pressed togeather.

its main function is to reinforce the resin rich area between a sub straight and a cloth product.....(resin by it self is very weak)
it is used to quickly build up bulk in a laminating situation.
it is also used for tabbing or tacking purposes.

woven cloth......this adds stregnth, as the cloth is woven with long strands in 2 directions......comes in many different weights......from very thin tight woven "veil" like cloth..."sold in small packages in wallmart and most hareware stores....uasually a bondo product......(a veil is a finishing cloth)
to a really thick cloth that can be as much as 40 oz.

bi ax cloth......this is a woven cloth product that is stitiched in several different directions....giving tremendous stregnth in all directions not just the lateral and vertical of the woven but, in a xyz fashion....most bi ax comes with csm on one side and cloth on the other. its weight rances from 8 or nine oz to over 50 oz......1708. is the most common used on this site......
1708 biax is 17 oz of cloth and 8 oz of matt stitiched togeather.

biax is uasually used in a structural situation because of its tremendous stregnth in all directions........3 layers of 1708 is all that is required for a really strong section of glass..........3 layers have the stregnth of a hull.

COMPOSITE "GLASS"
kevelar, graphite, ect
these are very exotic materials and are super strong. they use only epoxy resins and are far too expencive and strong for the needs of production boat builders.

RESINS........

polyester......
the weakest of all the resins.....(but still super strong)
most boats are made of this resin....and uasually the cheapest resin they can get.
will not bond to epoxy.
uses mekp catylist....
the catylest amount can be varied to regulate curing and working times....minimum 1.5% to 2.5% cat to resin ratio depending on heat and humidity
this makes poly very versatile, and the choice of 99% of production boat builders

there are two normal types of poly resin....waxed and unwaxed...

unwaxed is a laminating resin.....it will remain sticky for days and you are able to laminate over it up to 48 hours without further surface prep.

waxed is a finishing resin.....it contains wax and the wax rises to the surface after a slight cure......if it is used as a laminating resin....this top layer of wax must be ground off or the next layer will not stick properly.....
was is a release agent for polyester resins.


vyinalester sp?....
a poly based resin stronger than regular poly
also uses mekp

epoxy........known as "the glue
it is a two part mixture
50 50 mixture.... by far.....it is the strongest of all resins
bonds tenaciously to most substraights, is an exellent waterproofing material.
csm is not needed in epoxy situations as epoxy is strong enough to resist breaking in the resin rich layer between substraight and glass product.

it is very expencive....(twice as much $ as poly) for this reason, and because its tremendous stregnth is far more than nessary, boat manufacturers of standard pleasure boats do not use this product in production boat building.


++++++++++++++++++++++++++++++++++++++++++++++++++++++++
that is the tip of the iceberg my friend....

and its all i type in such a short time :)
any other questions or somthing i left out....just post back

cheers
oops
 
Last edited:

Bull54

Petty Officer 3rd Class
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Messages
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Re: Confused on Mats, cloths etc

WOW!!!!!!! Thanks! Now that is what I was looking for and I am sure it is only the tip of the iceberg.:D

Now for a quick question or two.

items like the 1708....where is this usually found? I mean is it carried in local stores or is it an online item only. I don't really want to spend 3-4 days driving all over the place only to find out most of the stuff I need is only on line. However, if available locally I have no prob driving to wherever I need to go in order to purchase it.

I know West Marine seems to be out there on their prices on most stuff.

Is woven mat or biax mat usually available locally also or on line?

Thanks for all the help in trying to help me understand this.
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: Confused on Mats, cloths etc

the 1708 bi ax is fast becoming a common product.....the department stores will not carry it....it is uasually found in a "glass specific" kind of store.....these stores....while harder to find, are around in all the major centers......call boat repair places and auto body shops to find out who there local suppliers are.

woven cloth and csm are uasually found in small pricy quantities at a local department store....(under the sales name bondo)

but check the specialty stores first....as the quantities you want are far more than the dept stores can handle.

read the hull extension thread....it has detailed info and pics on glass....and a basic tutorial on glassing and products....

also....im going to add somthing i forgot on the first post.......check the first post again in a few minits reguarding waxed and unwaxed poly resin
 

oops!

Supreme Mariner
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Re: Confused on Mats, cloths etc

btw....the bondo brand resin you find in the dept stores is uasually waxed....and it does not say it on the label
 

Bull54

Petty Officer 3rd Class
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Jul 15, 2008
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Re: Confused on Mats, cloths etc

Thanks!!!!!!!!

Now I am gonna go read some more, still learning:D
 

GO OVRIT

Seaman
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Re: Confused on Mats, cloths etc

Thats some great info. I think it would be great as a sticky for quick reference.
 

Mark42

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Re: Confused on Mats, cloths etc

WOW!!!!!!! Thanks! Now that is what I was looking for and I am sure it is only the tip of the iceberg.:D

Now for a quick question or two.

items like the 1708....where is this usually found? I mean is it carried in local stores or is it an online item only. .....


Welcome to the Glass Cloth Confusion Club (the GCCC)!!!

I just when through this whole mess. You might have found a post of mine a few weeks old about this subject, and got lots of input from fellow members. The bottom line is I called a glass supplier and spoke to the owner who has lots of fabrication experience. We discussed my project, and he made his recomendation.

I ended up with the 1708 biax. Absolutely the most amazing glass product I have ever worked with. (most of my experience is in auto repairs and kit car building 15 years ago). Anyway, the 1708 is apparently the work horse of the average heavy duty layup. One layer over lightweight foam is so strong my kids can walk on the top I'm making, and I can sit on it (haven't tried standing on it myself until I get both sides laminated).

But there is a big downside to thick heavy weight cloth like 1708. It takes a lot more resin to wet it out. One gallon of mixed resin will wet out about 4 square yards of 1708. (3ftx3ft=1 sq yd, not 3ft x however wide your roll is). Compare that to 1 gallon will wet out about 10 sq yds of 6 oz cloth. So you can see the cost factor is directly related to the cloth weight. Especially if you use epoxy, which is about 30% more expensive than polyester/vinylester resin.

Unless you have a glass supplier near your, you are best off ordering from a website like fiberglasssite.com. But call and talk to the owner before you order your cloth.

So, what is it you want to use the glass for?
 

jonesg

Admiral
Joined
Feb 22, 2008
Messages
7,198
Re: Confused on Mats, cloths etc

Hi oops,

I used kevlar cloth with poly resin, seemed to wet out alright.
I've used woven graphite tape with poly too.
I think the trick with the graphite was to add it between layers of cloth.

I think of matting as the "fall aparticle" board of the boat world.
It saves money and builds up thickness in a hurry but I prefer to work with cloth.
 

ondarvr

Supreme Mariner
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Apr 6, 2005
Messages
11,527
Re: Confused on Mats, cloths etc

While you can use kevlar and carbon fiber in polyester laminates you don't get the same benefits as you do when using them with epoxy. Polyester resin isn't strong enough to take advantage of those fibers, plus it won't bond to them very well, so the cost out weighs any small advantage they may have over glass. VE resin will work better with them, but "S" glass will give great results at a lower cost and is easily compatible with all resins. You can get fabrics that are a combination of kevlar and glass or carbon and glass, they aren't that common, but can be special ordered.

For the most part normal E glass is all that's used in building boats and unless you find a marine composites engineer to design the boat, you won't know how and where to use the high end fibers anyhow.
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: Confused on Mats, cloths etc

Hi oops,

I used kevlar cloth with poly resin, seemed to wet out alright.
I've used woven graphite tape with poly too.
I think the trick with the graphite was to add it between layers of cloth.

I think of matting as the "fall aparticle" board of the boat world.
It saves money and builds up thickness in a hurry but I prefer to work with cloth.



jonsey.......you know im a fan of yours....but beware of somthing....

graphite isnt water tight......nor is polyester.....(in fact water is such a weird substance i dont know what is.....it finds it way everywhere)

graphite tends to fail catistrophicaly when fractured......what that means is....if water intrudes into the graphite....then freezes....it will become fractured....(the expansion of the water will give microscopic fracturers to the graphite)

when graphite fails.....it shatteres......see all the broken hockey sticks on the ice....or remember that shattered fly fishing rod......or the tunnel boats that just seem to "explode" ?

when you store your boat for the winter....keep it warm so there is no freezing..........chances are even if it does freeze youll be ok....but there is that one chance in 100 that :eek:

cheers my friend.......and congrats on going composite....that takes nads !

cheers
oops
 

redfury

Commander
Joined
Jul 16, 2006
Messages
2,657
Re: Confused on Mats, cloths etc

My first experience with fiberglass ended with me having a quart of burning hot resin cooking in a plastic container I had mixed it in as I feverishly tried to wet out and apply cloth to a repair I was doing on my old van. Never read the directions well, never made the attempt to find out what the heck I was doing.

I've learned so much since then and haven't even touched a container of resin. I feel confident that my efforts will be much more successful when I give it a go again.

The important thing is to plan everything out. Something I've learned here. Make sure you have your clean up supplies handy, and work methodically.

As far as trying to really get a grasp on the different fiberglass that you can use, you should go find yourself a fiberglass boat building/restore book at the local library and give it a good read. They say knowledge is power. While iboats is great and you can learn a lot, having it all in book form is a good way to get a real grasp on what fiberglass and boats is all about. Then, once you've armed yourself with some book knowledge, you'll have a really good grasp on the application questions you seek answers to. I really can't recommend reading a book about it more.

Now as far as my specific knowledge about glass goes ( watch out, here comes all one line of it! :eek: )....

3/4 Oz. CSM is really good for building custom items, like a custom dash, or anything with compound curves. The reason is that you can "distort" it without completely compromising the shape you are trying to make. CSM tears, so you can push it into corners without folds, etc. Those custom sub boxes you see on "Pimp my ride"? CSM layed over a wooden frame with cloth stapled to it...the CSM adds the stiffness and strength. Only real problem with an CSM though is that you end up with the "hairs" coming loose and gumming up the works, so it's probably the messiest of the fiberglasses to work with.
 

Bull54

Petty Officer 3rd Class
Joined
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Messages
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Re: Confused on Mats, cloths etc

This is the section I am trying to get all the info on so I can replace it. It is the hatchway from the cabin out to the front deck. Where you put out the anchor, so it has to be strong enough to stand and climb thru to toss the anhor. It has been replaced once by the old owner and they replaced it from the outside instead of the inside. It is raised about 1/8-1/4" higher than the regular deck so I want to make it flush with the deck.

I guess maybe that is why I am so confused, you have cloth and mat for sturdiness, you have it for smoothness, then you have all the resins that can make it pretty and make it structurally sound. Hell I just want it to look look when I am done.:D So I want to make sure I use the right tools for the right job so to speak. I know me I am not going to want to do it twice.:D

You guys are great with lots of great info thank so all so much.

817003.jpg
 

redfury

Commander
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Jul 16, 2006
Messages
2,657
Re: Confused on Mats, cloths etc

Well, you should be able to replace/repair that and get it to look good again...you have a few options. You can use plywood as a base and then tab that in from underneath. That'll leave the thickness of the hull for you to laminate glass on top of and sand/fair out to the smoothness that you want. To protect the wood underneath, you could put a layer of CSM over it or coat it with bilge coat.

If you end up with a less than desirable result, you could simply put anti skid paint on the repair area and it'll still look good.
 

Bull54

Petty Officer 3rd Class
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Messages
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Re: Confused on Mats, cloths etc

The way the did the previous repair job, was they have the original deck piece they cut out, then they placed 2-1/4" thick pieces of wood, then reinforced that with 1/2" plywood. However, none of the wood was glassed in, it was just screwed in for support. It is wet and was starting to rot. The only piece that was glassed in was the original deck top they cut out.

I realize that this small project is NOTHING compared to you old salts and your big projects but if you have never done anything like this before, it is a MAJOR ordeal to a rookie.:D

You guys are great and I am still reading and reading and learning lots. But I am still getting confused on some minor issues but I think I will be able to get them straight before too long.:D
 

redfury

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Re: Confused on Mats, cloths etc

No question is too small to ask. They've been asked hundreds of times and answered the same. Sometimes you just can't find what you are looking for in a search of the forums. That's when you ask the question. Sometimes you'll figure out the answer, but want reassurance that you are coming to the right conclusion. Again, ask away. Better to ask and be answered, then never ask and have something go horribly horribly wrong, and then have to ask how to fix it ;)
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
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12,932
Re: Confused on Mats, cloths etc

No question is too small to ask. They've been asked hundreds of times and answered the same. Sometimes you just can't find what you are looking for in a search of the forums. That's when you ask the question. Sometimes you'll figure out the answer, but want reassurance that you are coming to the right conclusion. Again, ask away. Better to ask and be answered, then never ask and have something go horribly horribly wrong, and then have to ask how to fix it ;)


guys........this responce is why i love this forum......guys here allways chip in and help......each boat that comes out of these forums is trully a group effort, and we all feel each sore back, or glass itch :eek:
 

Bull54

Petty Officer 3rd Class
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Messages
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Re: Confused on Mats, cloths etc

You guys and this site are awesome!!!!!!!! Thank you for being here for us rookies! I am still reading and learning BEFORE I get the supplies I need as I want to make sure I have my ducks in a row before I start. Just hope I can pull this off.:D
 

jonesg

Admiral
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Feb 22, 2008
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Re: Confused on Mats, cloths etc

jonsey.......you know im a fan of yours....but beware of somthing....

graphite isnt water tight......nor is polyester.....(in fact water is such a weird substance i dont know what is.....it finds it way everywhere)

graphite tends to fail catistrophicaly when fractured......what that means is....if water intrudes into the graphite....then freezes....it will become fractured....(the expansion of the water will give microscopic fracturers to the graphite)
cheers
oops

I laminated it within layers of cloth,
I start a molded peice with gelcoat first in the mold, then resin, light cloth, heavier cloth then CF tape where needed then more cloth to encapsulate it.
When the part is pulled you can feel the extra rigidity of the CF.
It also attracts lightning bolts to add to the fun.
 
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