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Re: paint
By:Paul G. Jacobson
Date: 11/14/1999, 1:00 am
In Response To: paint (Pete W.P.)

> Hi folks,

> Nxt on the list is paint. I want to paint the wood, then cover it with
> glass and epoxy as opposed to painting ONTOP of the glass and epoxy, which
> leaves the fragile paint more vulnerable to scratches.

Thre are several tough paints that are harder than your epoxy. Look for them.

> I would rather have
> the paint encapsulated and covered with glass cloth.

The idea of painting over the epoxy is that the paint protects the epoxy from UV damage. If the epoxy is over the paint then you have to cover everything iwth a layer of varnish that contains a UV blocking material. These varnishes tend to yellow, which affects the perceived color of your paint.

> Heres the question
> tho... what kind of paint does one paint on the UNepoxied wood?

Paint is a mixture of pigments and a liquid base or medium, in which it is suspended. Ideally the medium shouldbe reasonalby clear with no color of its own, and dry in a reasonable period of time. This medium can be linseed oil (thus, oil based paints), latex rubber, alkyd resins, polyurethane resin, epoxy resin, casein (a milk protein), albumin (an egg protein), honey, wax, various congealed tree saps -- heck the list can go on and on.

Paint usually sits on the surface of whatever is painted. Stains usually soak in.

If you put a layer of paint on the wood, and then cover it with epoxy, the paint will create a barrier that keeps the epoxy from penetrating the wood fibers. How strong is your paint holding on to the wood?

If you buy a paint made with an epoxy base (meaning that someone has added pigments to epoxy resin) then it might work like the boatbuilding epoxy, or it might not. Remember, this stuff is being formulated as a cosmetic covering, not as a structural material.

> Procedure
> ? Do I seal the wood first with a coat of epoxy and then paint? Schade in
> his book mentions "epoxy based paints"... whats that?

This sounds like half of a good idea. You really want your paint as the top coat or final coat so that it can protect the fiberglass job.

Epoxy based paints use epoxy resin as the medium. You can find some at most home centers. You will find some that are used for floor coatings, and for refinishing bath tubs. Boat supply stores sell paints for fiberglass boats which work well.

> At anyrate, I'd like the paint to be as permanent and protected as possible.

Rethink this. You use the paint both for decoration and for protection fo the structural materials. Using structural materials to protect the paint is rather uncommon.

> Lastly, does a painted hull weaken the epoxy bond if painted on wood
> first, then glassed and such?

Yes. in this case the bond of the fiberglass is limited to the strength of the bond of the paint with the wood -- and those types of bonds do not tend to be very strong. How weak are they? Well, would you use that paint as a glue? I don't think so. Epoxy, on the other hand is a very strong glue.

> If so, would pin striping be ok done this
> way if the process weakens the bond?

The small areas covered by pinstiping usually are insignificant. The problems come from covering large areas with solid coats of paint.

Hope this helps

Paul G. Jacobson

Messages In This Thread

paint
Pete W.P. -- 11/13/1999, 1:44 pm
Re: paint
Bram -- 11/14/1999, 11:02 am
Re: paint
Paul G. Jacobson -- 11/14/1999, 1:00 am
Re: paint
Dean Trexel -- 11/13/1999, 2:49 pm
Re: paint
Brian -- 11/13/1999, 8:55 pm
Re: Isocyanate Warning!
Ian Johnston -- 11/13/1999, 3:16 pm
Re: Isocyanate Warning!
Pete W.P. -- 11/14/1999, 1:03 pm
Re: Isocyanate Warning!
Tom P -- 11/14/1999, 10:47 pm