Best way to apply mat and poly resin on new deck?

[Pst76]

I am close to finalizing new stringer and deck project on a 19ft fourWinns I/O. When I place/fit the new decking (1/2" marine) I plan to overlay with mat and poly resin. I did a smaller boat a few yrs back and just poured resin over mat and spread with a blade worked well but smaller area. Is this the best way or is there a better way, also should I prep the surface first to make it tacky? Any suggestions appreciated.<br />Thanks

 

[prockvoan]

Re: Best way to apply mat and poly resin on new deck?

You can run a course sanding pad over the wood first,lay your cloth out,then mix your resin,pour it out and spreed it with a plastic blade or you can use a roller.Just have some acetone ready for clean up.Note* be ready to mix more resin as needed.

 

[ondarvr]

Re: Best way to apply mat and poly resin on new deck?

Coat the wood with resin before you apply the glass and let it get hard. You want the wood to soak up as much resin as it can, this will help it last much longer. Then spread some resin around on the wood before you put the glass down, it will be easier to wet it out this way.

 

[tengals123]

Re: Best way to apply mat and poly resin on new deck?

yep, lay a coat of resin down first. lay the cloth/mat on the resin roll flat and give it another coat. Hit it with one more coat the next day to seal it properly.<br /><br />cheers

 

[JasonJ]

Re: Best way to apply mat and poly resin on new deck?

I like to liberally apply resin to the wood first so as to penetrate into the wood and become tacky, immediately followed by the mat, then liberally apply more resin to saturate the mat. I don't like the concept of applying to the wood, let it cure, sand, and then the layup. Too many secondary bonds. If you use plenty of resin, you have a single bond that has penetrated the wood and mat rather than layers sitting on top of each other, and you don't have the resin leaching out of the mat.

 

[Pst76]

Re: Best way to apply mat and poly resin on new deck?

Thanks guys, I like the thought as JasonJ mentioned to get everything down before it cures.Would eliminate any potential bonding issues. May get a little messy laying cloth though once tacky. Area is approx 10'x 8' Sounds like a cool day in the shade and an extra set of hands around. Thank again.

 

[ondarvr]

Re: Best way to apply mat and poly resin on new deck?

You will be better off pre-coating the plywood with resin for a couple of reasons.<br /><br />1. All wood will absorb the resin at a different rate and amount, even different areas on the same sheat of plywood. If the wood sucks up more resin than you expected, it will take resin away from the glass and leave it dry. If it doesn't absorb the resin then you have a resin rich area and it will crack easier.<br /><br />2. When you pre-coat, it will allow the resin to soak into the wood longer. When resin cures it creates heat, heat make it cure faster, so the more resin and glass you put on at one time the faster it will cure and the less it will absorb.<br /><br />3. There will be no secondary bonding issue unless you use resin that has wax added to it, or you wait more than a day or two in very warm weather between coats.<br /><br />4. Wood can have resin in it (normally in the knots) that will stop the polyester resin from curing correctly. If that happens when you <br />pre-coat then it is easy to spot and correct, if it happens when you do it all of it at once, then you have to grind out all of those areas and patch them.

 

[Terry H]

Re: Best way to apply mat and poly resin on new deck?

I'm sorry On, maybe you are familiar with epoxy, but with poly resin you need to finish your layup all at once. You should thin the resin and paint onto the plywood,and as soon as you can lay your glass down start the layup, do all the layers in one session, one layer at a time. Soon as you can start filling the weave of the glass get her done. If you have everything ready and organized you could have the deck ready for paint in an hour or two. You don't Wait to paint till the resin is cured tho. Chief

 

[ondarvr]

Re: Best way to apply mat and poly resin on new deck?

Sorry Chief<br /><br />I do Polyester for a living, I currently work for a very large polyester resin and gel coat company in technical service and sales. At the last company I worked for, I was in charge of the marine market in North America, then that company was sold to a larger one. At one time or another I have been into most large boat builders in the US and Canada. <br /><br />My job now is to recommend specific resins and gel coats for each application, then teach and assist them in using the products correctly. This is not only in the marine industry, but all products made with resin and gel coat.<br /><br />On this project there is no problem with resin coating the wood, then letting it get hard. You do not need to finish a polyester layup all in one session, if you did then almost every boat made today is done incorrectly. If you use a resin with wax in it, or a DCPD based resin, then yes, it should be sanded before the next layup if it sits too long. If you thin the resin very much, you will only weaken it, styrene will make resin brittle if too much is added.