epoxy over acrylic paint?

i am having a friend paint my canoe paddle and i would like to put a layer of glass and epoxy over it after. I am concerned that the epoxy will ruin the paint. anybody tried this before? also looking for a supplier for glass and epoxy.



thanks Mr. Green

Never had a prooblem wit dat…

– Last Updated: Mar-04-10 2:27 PM EST –

me'self as long as de acrylic has adhered ta de paddle material properly. System Three or West be good epoxies.

P.S.... put a couple coats o' good marine varnish wit UV inhibitors over de epoxy after it's cured fer awhile or it'll git milky.

FE

It’s too bad that you need to preserve
the paint job, because the paint layer puts a limit on how effectively the glass and epoxy are bound to the paddle. I don’t know of any paint, except perhaps epoxy paint, that sticks as hard to wood as epoxy.



When I have glassed a varnished paddle, I have stripped off the varnish and sanded the paddle.



Are you wanting to glass over the paint to protect the paint, or to protect the paddle, or both? Unless you are putting the paddle to pretty hard use, maybe you’re better off skipping the glass job. You can touch up the paint when needed.

some questions

– Last Updated: Mar-04-10 10:31 PM EST –

...... your paddle , is it a manufactured paddle that already has a protective finish on it ... is your friend painting directly over that factory finish , and if so what is that finish ??

West System 105 resin and 207 hardner are about as clear as you can get in standard marine grade epoxies (also there is no amine blush to deal with when using 207 hardner) ... you'll want to use a UV urethane or varnish (Spar) over the expoxy ... good idea to maintain that UV coating yearly too .

Since your paddle will most likely have all it's grain already sealed either by the factory finish or the Acrylic paint job (or both) ... you can't expect the epoxy to be absorbed (bite) into the wood grain (it is a wood paddle isn't it ??) ... You probably won't be sanding (etching-toothing) over your friends' paint job in order to get a good bite for the epoxy (mechanical bond) , so that's another factor to consider when it comes to best adhesion of the epoxy .

Sounds like your friend is going to do a really nice paint job on your paddle , something you are really wanting to keep protected , I can understand that .

Between the epoxy (even w/207)and the spar overcoats , in time you "will" get some ambering .

I can not say from experience about epoxy over acrylic paint , if there will be any negative chemical reactions (not all acrylics are created equal) ... but I doubt there should be any negative reactions ... some acrylic paintings are coated by the artist with epoxies for special effects .

My suggestion would be to try and do a mock up surface ... a piece of wood plank , coat with whatever you believe is the factory finish on your paddle , paint over the factory finish with the acrylics your friend has used ... when all is cured and ready , go over that with a couple coats of the epoxy (resin/hardner mix) and a swath of glass cloth ... this is a test mock up just to see how well you it takes and what you feel about it ... you could do the same thing thing (another mock up) just using the spar urethane or varnish too .

Your paddle should be fine just waiting around after your friend does the paint job (not being used of course) ... no need to jump right into the epoxy or other top coatings until you've attempted the mock up(s) , and are comfortable , right !!

You can get glass cloths from many places , especially on-line ... "a hobby shop that's about RC cars and airplanes" will have glass cloths , usually E glass in 3/4 oz. , 2 oz. , 4 oz. (decent stuff cause the modelers have to depend on it to make wings and fusalages etc.)

Or you could just use the spar urethane (apply several coats - 4+) , and keep it maintained according to use ?? ... if you do just use the UV spar directly over the acrylics , you probaly should use an oil base spar urethane (Minwax) or varnish instead of a water base .

Let us know how it goes , ok ...

glass coat
the whole reason for the glass is to reinforce a paddle with a fine crack down the middle. Thanks very much for the advice I will keep you updated.

well if it’s not already painted …

– Last Updated: Mar-05-10 12:19 AM EST –

...... there is also the option of a thin dutchman inlaid to span the crack (easy job with a router , ploughing bit and simple homemade jig) ... epoxy the dutchman into the crack and at the same time get the epoxy to oozz thru the crack by heating the wood with a hair dryer just before placing the dutchman (sand dutchman down to finish surface after epoxy has dried).

Why not paint over the epoxy and FG?
If the purpose of the epoxy and fiberglass is to reinforce the damaged blade and the purpose of the paint is strictly cosmetic, it would seem that you should paint over the epoxy. That way the paint will provide the UV resistance necessary to protect the epoxy. If you want to protect some sort of elaborate paint job, you could put a coat or two of varnish over the paint.



Assuming that I understand your situation correctly, I would do the following.

  1. Sand the paddle blade to bare wood.
  2. Glue the crack with epoxy and clamp until cured.
  3. Apply a layer of 4 or 6 oz FG cloth saturated with epoxy.
  4. Apply additional epoxy to fill the weave.
  5. Sand the FG/epoxy layer smooth.
  6. Paint with a good marine quality enamel.
  7. If the paint job contains a graphic or otherwise needs to be protected, a coat or two of quality varnish could be applied over the paint.



    Marc Ornstein

    Dogpaddle Canoe Works

    Custom Paddles and Cedar Strip Canoes

thanks
that is a great idea i will do that!