polyester resin

[Paul eagen]

I picked up a pint of poly resin just to get used to working with it. When I used it, it did not soak in to the wood. Just wondering if it was something I did wrong or is it because it had wax in it. It was Evercoat polyester resin. The label said it was thixed and waxed.

 

[lowkee]

Re: polyester resin

I doesn't really soak in, it coats it. Very little of it will actually soak into cleanly cut wood. If the wood has frayed edges, it will soak in more on those parts. The wax is to make it fully cure for sanding (or the final coat) and won't prevent it from soaking into anything.

 

[Paul eagen]

Re: polyester resin

Thank you for your reply. So if I want something to soakinto the wood fo waterproofing I should use epoxy? I am going to be putting a new deck in my boat this fall, and I am trying to get all of my ducks in a row before then.

 

[Mark42]

Re: polyester resin

What are you trying to water proof? If you are concerned about water damage, consider starting with pressure treated wood, then glass with poly resin and it should last longer than you will own it.

Here are some links to pressure treated lumber in boats by the APA, (Engineered Wood Association)

http://glen-l.com/wood-plywood/fiberglass-plywood.html

For BEST performance of plywood in boat manufacturing, APA recommends the use of treated plywood...

http://www.glen-l.com/wood-plywood/boatbuilding-plywood.html

http://www.glen-l.com/wood-plywood/marine-plywood.html

 

[jonesg]

Re: polyester resin

I picked up a pint of poly resin just to get used to working with it. When I used it, it did not soak in to the wood. Just wondering if it was something I did wrong or is it because it had wax in it. It was Evercoat polyester resin. The label said it was thixed and waxed.

if its thixed it won't soak in for beans.
You need regular resin, unwaxed is best because thats mostly what you will be working with, final coat can have wax if it will be sanded, I use unwaxed exclusively for construction.

CAbosil , when added to resin, makes it thixotropic, a non flowing quality , unless vibrated it will not run ( like ketchup). I think thats what you bought.
Its formulated for overhead and vertical work but if you need that you can just mix your own up.

 

[ondarvr]

Re: polyester resin

Even penetrating resins don't really soak in all that well, so don't stress over it. Plus neither type of resin will waterproof wood all that well with out a layer of glass.

 

[brospano177]

Re: polyester resin

how can one tell what resin a boat was originally made with?

 

[ondarvr]

Re: polyester resin

The easiest way to tell is that unless its a custom built, high end, high performance mega $$$ boat, then its polyester.

The other case for epoxy would be a wood boat thats been covered with glass.

 

[Mark42]

Re: polyester resin

The easiest way to tell is that unless its a custom built, high end, high performance mega $$$ boat, then its polyester.

The other case for epoxy would be a wood boat thats been cover with glass.

Another way of looking at is this: If its not aluminum, its probably polyester.

 

[oops!]

Re: polyester resin

Even penetrating resins don't really soak in all that well, so don't stress over it. Plus neither type of resin will waterproof wood all that well with out a layer of glass.

waxed or un waxed.....coat the wood with resin, and wait till the resin is just about cured....then lay a layer of matt over it...and coat it in.

how can one tell what resin a boat was originally made with?

most/all are poly.....contact the mfgrs...i was told from the mid ninety's....searay started using ve resin........ondarvr might tell us different....take his word over the manufacturers

Another way of looking at is this: If its not aluminum, its probably polyester.

lol.....aint that the truth....!


ok.....the trick is ...to coat the wood with resin ....just till it starts to cure....then add the glass and more resin. no air and glass till its done.

the wax is a coating that keeps the glass impoervious to water penetration.........lol.........i use laminating resin and add air dry...(wax)
on the outer layser of resin........

if your not sure.....just coat the heck out of it till the glass is fully saturated.
but remember,,,,50 glass 50 resin it the regular mix.....


resin is brittle with out glass so dont go over board.......

 

[Mark42]

Re: polyester resin

Vinylester resin is commonly used in the gel coat because it resists water absorption better than polyester. Its more expensive than poly, so they use it in the gel coat, then finish the lamination with poly. Vinylester is also more flexible than poly, making it more resistant to spider cracking. Another good property for gel coat.

 

[rngale]

Re: polyester resin

Vinylester resin is commonly used in the gel coat because it resists water absorption better than polyester. Its more expensive than poly, so they use it in the gel coat, then finish the lamination with poly. Vinylester is also more flexible than poly, making it more resistant to spider cracking. Another good property for gel coat.

There are several gel coats that manufacturers use, some are made with a vinyl ester resin for a better barrier coat and some are made with a thermal resistant resin to avoid print through in heavy layups, and some are a blend of the two, for example Armour coat. The most common method for small production boats ( at least here in Maine) is to use the thermal resistant gelcoat with the skin coat ( first layer of 1.5oz csm) with vinyl ester to not only act as a barrier coat agianst water but to cut down on the chance of gelcoat blisters from both water saturation and heat/cooling cycles.

When working with vinyl ester resins you will notice that it will stay sticky feeling longer and that scuffing it before your next layup will plug up sandpaper more. Its the nature of the resin not the lack of wax.