What kind of fiberglass/epoxy to use?

[KMD]

I have a 37' Chesapeake bay built. I am building a new deck for the boat, I built all the floor trusses and supports out of presure treated lumber. I am going to use 3/4 " Marine plywood for the deck material. I want to fiberglass the top of the deck but do not know which type of fiberglass matting to use. I do not know anything about fiberglass cloth/epoxy/resin/etc..... below was the method I was going to do this project in could I get some comments if I am doing this correctly?


The method I was going to use was to put some type of resin and cloth on all the edges of the plywood , then once the glass dried I was going to treat the bottom of the plywood with some type of wood preservative (Cupinal, or some other environmentally friendly treatment.) Next I will screw the plywood to the floor then glass the entire deck with some type of fiberglass and epoxy. This is a workboat so it doesnt have to be a yacht quality finish, I was going to paint the floor when I was done.

[Gilbert]

Hi KMD,
I am posting a transcript of an article that was in Professional Boatbuilder magazine some years ago that I think will be helpful to you and maybe some others as well. See the attachments.
Best Wishes,
Gilbert

[boatbuilder.org]

Dynel makes a great abrasion resistant surface, and use MAS low viscosity resin and the no-blush slow or medium hardeners <http://www.boatbuilder.org/epoxy.htm>
---Joel---

(360)-790-0577

[unhippy]

KMD,
Ditto on the MAS epoxy. I've worked with West and System 3 and I like the MAS better. Their medium hardener gives a relatively quick cure even in cooler temps. and produces little or no blush.
Some people would use polyester resin and chopped strand mat because it's cheaper than epoxy but be aware that it will delaminate eventually.
If you've gone through the trouble to use quality materials so far then it seems like a good idea to use a good quality epoxy resin and glass.
Good luck!

unhippy

[chandler]

I agree with boatbuilder and unhippy. MAS is easy to work with and doesn't smell too bad, dynel is good stuff, for non skid on a workboat, mix raw sugar rough sugar crystals in the top coat.

[JR-Shine]

We use the Marinepoxy and 6 oz. cloth for most of our decks - its cheaper than the name brand epoxies and works just as well for these type applications. Non-skid additive is very cheap and it will suspend in the paint of resin you use which gives better results than sugar, salt, sand, walnut shells, etc.....

[drs3317]

JR-Shine,

Do you use more than one layer of 6oz on your decks? I'm now ready to glass the cockpit in my 31'. I have 3/4" MDO which will be epoxy coated first. Just wondering if I should use more than one layer of fiberglass for added protection? Also where do you get Marinepoxy?
Thanks,
Danny

[cyclops]

There really is no such thing as a marine epoxy. There are better quality epoxies. Used in boats, planes, cars, trains,etc.--www.oneoceankayaks.com has a rating of epoxies and why some work better.

[JR-Shine]

Originally Posted by drs3317

JR-Shine,

Do you use more than one layer of 6oz on your decks? I'm now ready to glass the cockpit in my 31'. I have 3/4" MDO which will be epoxy coated first. Just wondering if I should use more than one layer of fiberglass for added protection? Also where do you get Marinepoxy?
Thanks,
Danny

Marinepoxy is a brand we sell at boatbuildercentral.com. I would prefer to use one layer of 9 oz. instead of multiple layers of lighter cloth. Its less work and less chance of mistakes.

Joel

[chandler]

KMD
A couple of things...if it's not too late, avoid pressure treated lumber, it's very unstable new growth southern yellow pine, with the epoxy and glass deck if properly done shouldn't leak, spruce would be lighter and cheaper. You should really seal both sides and all edges of the ply with epoxy, skip the cuprinol.

[cyclops]

I did not know the public could obtain Cuprinol any easier than pesticides, EPA?

[unhippy]

I think Cuprinol has a new "environmentaly friendly" formula.
I still wouldn't recomend drinking it though.

unhippy

[Deering]

Concur with Chandler. Epoxy all sides. Keeps humidity variations in the air from causing swelling and shrinking of the plywood which leads to stresses on the attachments and delamination. Just epoxy, no glass required on the bottom unless you want to stiffen the deck.

[unhippy]

Originally Posted by Deering

Concur with Chandler. Epoxy all sides. Keeps humidity variations in the air from causing swelling and shrinking of the plywood which leads to stresses on the attachments and delamination. Just epoxy, no glass required on the bottom unless you want to stiffen the deck.

AAAaah yes. The encapsulation doctrine! You are absolutely correct!

unhippy

[chandler]

Yes cuprinol comes in all kinds of user friendly shades these days..It's not the cuprinol our fathers used.