CSM for use with epoxy

[Boo2]

Hi,

I've read here that normal chopped strand mat (CSM) can't be used with epoxy resins because the binder is specific to polyester resins and doesn't disolve in epoxy (or something). Can anyone tell me what the name is for CSM which is suitable for use with epoxy resins ? And ideally a place I can buy small quantities ?

Thanks,

Boo2

 

[Tradewinds]

East Coast Fibreglass has it.

See here.

 

[Boathook]

West epoxy also do a csm for epoxy resin. Have to buy a 'tub' and I can't remember how much I paid.

 

[Quandary]

Mat for epoxy

Its called powder bound mat, simply referring to the method of (almost) holding it together in a sheet or roll until you get the resin on to it, most specialist fibreglass suppliers have it and will sell it by the metre in various weights.

Sorry, already comprehensively answered in the link provided by Tradewinds above.

 

[misterg]

Can anyone tell me what the name is for CSM which is suitable for use with epoxy resins ? And ideally a place I can buy small quantities ?

"Powder bonded"

CFS

Glasplies may be able to supply it, but I don't see it listed in their on-line shop.

Andy

 

[oldsaltoz]

Hi,
I've read here that normal chopped strand mat (CSM) can't be used with epoxy resins because the binder is specific to polyester resins and doesn't disolve in epoxy (or something). Can anyone tell me what the name is for CSM which is suitable for use with epoxy resins ? And ideally a place I can buy small quantities ?
Thanks,
Boo2

Also note, apart from the binder being a problem, the large voids in CSM means you will also use a lot more (up to 3 times more) resin and this not only adds a lot to the cost but can actually weaken the whole job.

The mat for epoxy is referred to as cloth, not mat and has much less voids in the weave.

Good luck and fair winds.

 

[VicS]

Also note, apart from the binder being a problem, the large voids in CSM means you will also use a lot more (up to 3 times more) resin and this not only adds a lot to the cost but can actually weaken the whole job.

The mat for epoxy is referred to as cloth, not mat and has much less voids in the weave.

Good luck and fair winds.

Rather than use the powder bound CSM you'd recommend what..biaxial fabric .. for use with epoxy resin.

.

 

[mitiempo]

I have used woven cloth in light weights and for bonding anything structural biaxial 1708, which is a stitched (not woven) roving with epoxy compatible mat attached to one side. It is a lot easier to use than mat, stronger by a large margin, and leaves a smoother finish. Less layers are needed as well.

 

[Bosun Higgs]

Hi,

I've read here that normal chopped strand mat (CSM) can't be used with epoxy resins because the binder is specific to polyester resins and doesn't disolve in epoxy (or something). Can anyone tell me what the name is for CSM which is suitable for use with epoxy resins ? And ideally a place I can buy small quantities ?

Thanks,

Boo2

CSM is a complete PITA to use with epoxy because the epoxy is so sticky and the csm rapidly breaks up into individual fibres. You end up with tools covered in a beard of glass and a poor finish on the job itself. Having tried it, I avoid it.

On a flatish surface one way round it is to put down a layer of csm and a layer of woven on top at the same time and then rely on your roller to get them wetted out. Or even a layer of polythene over the top before you roll. then left until hard. But you can only do that it its the final layer or you end up having to sand back.

 

[Tradewinds]

CSM is a complete PITA to use with epoxy because the epoxy is so sticky and the csm rapidly breaks up into individual fibres. You end up with tools covered in a beard of glass and a poor finish on the job itself. Having tried it, I avoid it.

Having used the correct CSM with epoxy this year I have to agree with you.

Using woven fabric is a relatively enjoyable & satisfying process. Using CSM with epoxy is the work of the devil.

I threw the CSM away & went back to cloth (what I did with CSM wasn't in a crucial area anyway).

 

[oldsaltoz]

Rather than use the powder bound CSM you'd recommend what..biaxial fabric .. for use with epoxy resin.
.

The type and weight of the cloth to be used would very much depend on what you are building / repairing.

Roving's are good to top finish, Biaxial can be strong provided the layers are rotated, triaxial or crows foot will also provide a strong base, again it should be rotated as eaxh new layer is applied.

The weight or thickness will depend on how much you need for strength and or flexibility.