Epoxy and Mat

[i386]

I was reading this article (pdf). It says not to use epoxy resin with CSM (chop strand mat). I've never read that anywhere in this forum. Is this an old concern that no longer applies? Do the solvents in epoxy resin not break down the binder like polyester does? I've already purchased 25 yards of CSM and am planning to use epoxy on my restoration. I'm just trying to get my ducks in a row here.

 

[ondarvr]

Re: Epoxy and Mat

No need for mat with epoxy.

Do a search, it comes up frequently and you should be able to find more details about it.

 

[oops!]

Re: Epoxy and Mat

nope....no matt with epoxy.......matt us used with poly to build a resin rich layer between the layers of cloth..(it is also used to build bulk)..dont need it with epoxy.....epoxy is really strong stuff.

search...epoxy vs poly...

coors....erik...wanna jump in here?

cheers
oops

 

[oops!]

Re: Epoxy and Mat

heh heh heh...... yer quick rvr

 

[jcsercsa]

Re: Epoxy and Mat

OHH i dont count ??? lol The the God here go by what they say !!! no matt !!! John

 

[i386]

Re: Epoxy and Mat

I've been here a while. I'm surprised I missed that. Well I have 25 yards of mat and 25 yards of 6oz cloth. I thought I'd need to alternate the two in my layup.

I'm ok using the cloth right?

Is it ok to use the mat on my top layer to get a smother finish with epoxy?

 

[oops!]

Re: Epoxy and Mat

sorry john !!


cloth is where epoxy shines......

"it used to be"....only when you used poly resin....some prefered matt for finish...some prefered very light tight cloth...(with poly)...different strokes...

what ya doin?.....ya might trade in the matt for cloth.....go to the manufacturers site for a lay up sched.

cheers
oops

 

[jcsercsa]

Re: Epoxy and Mat

I've been here a while. I'm surprised I missed that. Well I have 25 yards of mat and 25 yards of 6oz cloth. I thought I'd need to alternate the two in my layup.

I'm ok using the cloth right?

Is it ok to use the mat on my top layer to get a smother finish with epoxy?

yep you can , but [ and correct me if im wrong ondarvr } epoxy will smooth out petty nice so its not really needed !! and on the cloth I was going to go a little thicker , us the 6oz and then go with some 16oz or even thicker yet if you want , Is it just strait 6oz glass ?? you might even think on some woven !!! di you check out U.S. Composites,http://www.uscomposites.com/cloth.html
they tell you alot on the different types of glass !! John

 

[jcsercsa]

Re: Epoxy and Mat

sorry john !!


I know , thanks though !!! hahaha John

 

[oops!]

Re: Epoxy and Mat

i guess i just have trouble reffering to a young buck as ....


YOUR MAJESTEY

 

[jcsercsa]

Re: Epoxy and Mat

i guess i just have trouble reffering to a young buck as ....


YOUR MAJESTEY

hahahahhahahahahahhaahahahahahahaha Thank you about time some one noticed !!!!! hahahahaha

 

[i386]

Re: Epoxy and Mat

By the way. It's a little 14' boat. I'm replacing the deck and patching a few holes in the hull. The design is a little unusual in that it has no stringers. The way the transom is made is a little uncommon too. The splash well basically supports the weight of the engine (40hp max). It does not have a plywood core transom going across the stern.

 

[oops!]

Re: Epoxy and Mat

No prob.....

the epoxy will be an expencive way of doing the deck.....but youll be able to jump that thing !

the holes (since yer there) get from the inside

cheers
oops

 

[jcsercsa]

Re: Epoxy and Mat

By the way. It's a little 14' boat. I'm replacing the deck and patching a few holes in the hull. The design is a little unusual in that it has no stringers. The way the transom is made is a little uncommon too. The splash well basically supports the weight of the engine (40hp max). It does not have a plywood core transom going across the stern.

All your support is in the top and the foam,deck !!! on your transom on one of your pic you have posted is it steped in or is it solid where the motor sits couldnt really tell in the one pic ??
She going to be petty cool boat when she is done !! that 40 ought to push her petty good !!! John

 

[erikgreen]

Re: Epoxy and Mat

Wow, I can't even keep up. You got the best response first though, ondarvr is the prince of fiberglass. He has a little resin crown and a biaxial cape and everything

 

[i386]

Re: Epoxy and Mat

Yes, the cap is built like a tank. That is where the strength is. Also it's a tri-hull with the hull acting as stringers. If I could use composites instead of wood this boat would last forever. I don't think that's going to be very cost effective though. Anyway, where the engine clamps on the splashwell is heavily reinforced 2 or 3 inches thick. There is a small piece of plywood in the center of the stern also.

The engine is a 33HP Ski-Twin. I think the 40hp ones were called Big-Twins.

Anyway...

It is not my intention to turn this into another poly vs. epoxy thread but here are my reasons for choosing epoxy.

1. Since I cut the cap into two pieces and the cap is the main structural component I want as much strength as possible when I join it back together.

2. Being inexperienced with either resin, I find it more comforting to mix the same ratio of hardener and resin every time as opposed to adding varying amounts of catalyst to poly depending on the temperature outside.

3. I think I'll only need 2 gallons or less of resin (please correct me if this seems way off). In this quantity, epoxy is only about $40 more than poly. I can live with that.

 

[ondarvr]

Re: Epoxy and Mat

Not an E vs P thread here, they both work.

If I see it correctly, that hump under the plywood is another piece of plywood covered with glass, the small piece you can see is for the transom clamps to grab onto and not dig into the glass.

 

[i386]

Re: Epoxy and Mat

Not an E vs P thread here, they both work.

If I see it correctly, that hump under the plywood is another piece of plywood covered with glass, the small piece you can see is for the transom clamps to grab onto and not dig into the glass.

You got it absolutely right. It's two pieces of plywood glued up then glassed in. It's attached to the skin. The space to the left and right of it is just the skin. If it were not for the reinforced "box" in the center of the splash well the weight of the engine would just tear the skin off the boat.

You can see in this pic where peanut butter was applied to glue in the stern portion of the cap. This was the only part of the cap that was glued in. You can see on the left and right side where glue joint was. There was much more on the starboard side of the stern than port. I am very lucky that I got it out without damaging the skin.

 

[oops!]

Re: Epoxy and Mat

Wow, I can't even keep up. You got the best response first though, ondarvr is the prince of fiberglass. He has a little resin crown and a biaxial cape and everything

thats funny.....but totally true..!
one of the top pros in the us.

 

[BillP]

Re: Epoxy and Mat

Read the pdf article again...It says to use the correct mat with epoxy...mat made for polyester is what they imply not to use with epoxy...here's a cut and paste from the article:

Avoid chopped strand mat when using epoxy unless it is suitable for epoxy saturation. (i.e. Multi purpose mat or stitched mat);

Where are all you guys getting the info that says epoxy resin takes the place of mat in a laminate schedule? Engineering data and spec sheets from epoxy and glass mfgs saying so?

Bill P.