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Dan Dan is offline
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First recorded activity by BoatBanter: Oct 2006
Posts: 8
Default Peel Ply.. Please Help

Thanks John, but the DB1208 and the DB1808 have the mat stitched on so
there is no problem wit the binder. There is no binder. This stuff is
made specifically for epoxy.
Dan

John M wrote:
Mat unless it is specifically made for epoxy resin should only be used for
polyester resins.
The reason is the binder used to hold the mat together is polyester based
and will not dissolve with epoxy.

"Dan" wrote in message ...

Thanks FR. I have thrown the 6oz material in the trash.
Here is a stupid question, which way do you put down the DB1208, mat side
up, or mat side down against the substrait?

FR wrote:

He said.........

I am using West system epoxy. The material is about 6 mos. old. I am
bonding over fairing putty that was used to level the surface prior to
putting the fiberglass down. It was a clean and course surface. The part
I don't get is that it didn't even stick to itself. I did some repair
work using this epoxy and DB1808 and it is solid as a rock.



You have discovered that the 6 oz finely woven fiber glass that is
commonly sold by "fiberglass supply houses" is terrible when it comes
to adhesion properties. I have found this to be true regardless of the
resin type Epoxy, Vinylester or Polyester.

I think it is attributable to the tightly packed and twisted tows used to
make the material. It does not allow for good saturation.

Next time use a DB1208 and you will get the same results as the DB1808
and save a bit of weight. The glass mat sewn to the double bias strands
offer good saturation and great adhesion and a superior water proofing
layer.

I know of very few "pros" who use this stuff in fiberglass work but for
some reason it seems very popular with do it yourselfers.

In 28 years of fiberglass boat building with five different companies I
have never used this product in a commercially built boat.

My advice is to stay away from it unless your are building model boats.

frp