Mat is not very nice stuff, it absorbs a huge amount of resin without providing much strength. It has it's place in certain layups, but none of them are much use in a kayak other than saving money in the manufacturing. This is one explanation of why British boats can be shipped from the UK to the US and still end up no more expensive than domestically manufactured boats. Use mat to make molds, not boats.

You can make a boat with mat which does not use much glass and still have it seem pretty strong. A boat built with mat will be pretty thick which will make it stiff. When you push on the deck it won't give much. If you make it thick and heavy enough it will be able to absorb a lot of abuse just due to the big thick slab of resin involved. But the boat will be very heavy, it will not handle fatigue well and given the right hit, the skin will tend to shatter.

One use for mat is as the first layer after the gel coat so you don't get print-through of the cloth. If the cloth bothers you that much and you don't mind a heavier, more brittle boat, mat is a good solution.

> At the site of Nigel Dennis Kayaks, I did find the following specification
> for his ROMANY kayak layup:

> Deck - 2.5 oz C.S mat plus foredeck rescue patch of extra 1.5 oz mat.

> Hull - 2.5 oz C.S mat plus 8 oz cloth. 2 inch keel strip. Double thickness
> reinforced bow and stern.

> Inside seam - 2 inch diolen plus 3 inch glass cloth.

> Outside seam - 1 inch glass cloth.

> SO: It seems like the hull is 2.5 oz mat + 8 oz cloth, a total of 10.5 oz.

> Now, this is not a wokk core boat, so I wonder if this is all there is of
> fiber/core material in the hull. If 10.5 is enough, then 18 oz should of
> course be overkill. But so should 6 oz inside and 6 oz outside on a kayak
> built with 4mm marine plywood. The cloth alone would be 12 oz, which is
> more than the total on the Nigel Dennis boat.

> Is there something wrong with my thinking here?

> If the 18 oz cloths should be used for something, it seems like it would
> have to be the main cloth on an spoxy/glass only boat built using a female
> or male mould.

> Well, I am now going to learn more about composites. I guess it will be a
> nice journey.

> Jan Gunnar