Fiberglassing?

[amuh60]

I am fiberglassing douglas fir ledgers to hull side for fastening bunks.

Using West System epoxy resin. 1 layer of 1.5 oz Chopped Matt followed by 1 layer of 24 oz woven roving followed by 1.5 oz Chopped matt.

I fiberglassed all these layers in succession with 1 batch of epoxy.

Is this a technique? Any suggestions?

Thanks,

-ANDY

[Bob H.]

Andy, No pro here but, Id soak the fir with unthickened epoxy, mix up some cabosil with some high density filler to a mayonaise consistency, slather that on the fir, put that on the hull then coat the other side of the ledger fir, lay on a layer 0f 1708 biaxle with mat side towards fir, then a layer of heavy mat with another layer of 1708, cover with peel n ply fabric, helps to remove amine blush and leaves a nice smooth finish. When I use cloth the bigger or wider piece goes first then I stagger them back by 1.5 - 2" per piece. Sounds like overkill...but thats my middle name..BH

[amuh60]

What is the difference in 1708 cloth and the 24 oz woven 90? It seems that the 1708 is woven with chopped matt already stuck to one side of it? Is sandwiching a piece of 24 oz 90 woven between two 1.5 oz chopped matt not similiar in strength? also will this not support the bunks?

Thanks,

Andy

[Bob H.]

Andy, The woven cloth is very substantial cloth but at 90 degree angle only. The 1708 is at 45 degree angle and offers a better angular strength. The woven also is not good at making tight bends. the 1708 over a good inside fillet is the way to go for bonding. The mat i n the 1708 is for bonding to a well prepared surface and subsequent layers of say roven and another 1708. The mat has little strength to it more a bonding and cover fabric. To bond a cleat or ledger to the hull side which would never be seen, I would go with two layers of 1708, if its carrying a big load and your in doubt add the roven between layers, just lay it up in one shot and wet the cloth in big shallow plastic trays. The trays keep your epoxy "cooler" longer, take care in bubble removal before adding next layer, then peel n ply release fabric, next day remove fabric, give it a wash with water to get remaining amine blush.
The picture is of my ledgers under the deck, two layers of 1708 only. Notice gussets under ledger, all made from coosa and 1708. BH

[matt ciarpella]

Bob,
Where can I get me one of those water jacketed exhaust mixers you got there? In 4inch
Matt

[amuh60]

Thanks

Did you use epoxy or Polyester resin?

[Bob H.]

Andy, All epoxy for me...Matt, the exhaust elbow came from Tony Athens at Sea Board Marine...Top shelf stuff Tonys great to deal with. BH