i looked through a few pages on here but didnt see this question even though i am sure it is here somewhere. i am replaceing the stringers in my boat and i need to know what resin and type of cloth to use for this? i have seen some on ebay but not sure it is the correct stuff. i know i for sure need a epoxy resin but i think there are many different types? thanks

I would suggest using a biaxial mat like 1808 and a good epoxy. I've had good luck with the 635 thin epoxy from us composites.

Amen on all dat! 1808 is pretty much all you will need and the 635 is a great epoxy and way more cost effective than West System.


http://uscomposites.com/epoxy.html

The Knytex 1708 +/-45 on this page is also fine, for some reason i dont see the 1808 +/- 45 (which is what i normally use) but they list a +/- 90. The +/-45 is easier to drape over stringers and just so ya know the numbers denote the weight of the fabrics used. The first two (18 in this case) are the weight in ounces per sq.yrd. of the fabric and the second two ( 08) denote the approximate weight of the mat per sq.ft. In this case 08 is 3/4oz mat. The +/-## is the angle of the warp and fill fibers across the length. Stick with +/-45 for just about everything.

http://uscomposites.com/specialty.html

The US composites 1708 biax I got awhile back is good stuff, expensive but good. I got a roll from another supplier and it looks like b-stock, definitely not a-quality. They've been busy tho, so it may take a couple days to get your order out.

how much do you think i need, i am replacing 3/4 of the stringers in a 27' baja 250 along with the 2 bulkheads (i think thats what they are called?) and then i guess the molded floor is gonna have to be pulled out so i am going to have to lay a wood floor now. another question that seems to be the great debate s what kind of wood to use? the original stuff looks to be normal, not marine grade, 2x10s and 2x6s so is that what i should use to replace it?? i plan to resin this stuff to the point that water cant get in no matter what wood i use.

I would get 20 yards or so to start, figure everything you do will need atleast two layers and tabbing. For stringers use a good outdoor rated 3/4" plywood, the only difference between that and marine rated is voids. If you can swing it money wise it always better to use marine but it is acceptable to the outdoor rated as long as everything is fully encapsulated. Dont use any 2Xanythings, if you need something dimensionally larger than 3/4, laminate up some pieces using the plywood. Use a piece of .75oz mat between the layers for best bond. Dont forget to round over any corners with a router to help the laminate make the bend.

aren't some matts incompatible with epoxy due to the lack of styrene in epoxy to break down the binders in the matt?

not the bi-ax's they all have a stitched mat but yes thanks for bringing that up (forgot he was using epoxy). For anything between the wood you can probably just use the 1708, technically mat has no place in an epoxy system and you can actually use a 1700 or 1800 bi-ax if you can find it. For simple stringer jobs like this no point in over complicating it though.

I knew there was something to that...

yea . . my friend Matt doesnt like epoxy . . . I think someone did a telephone survey of people named Matt and yes . . . its true most dont like epoxy. . . . . And most Daves dont like Parmesan cheese