Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Painting, Finishing and Care. => Topic started by: tigertiger on December 30, 2009, 01:23:53 am

Title: Primer on epoxy question
Post by: tigertiger on December 30, 2009, 01:23:53 am
I have a hull that has been treated with epoxy resin.

Will rattle can acrylic primer work on epoxy, or do I need a special primer?
Title: Re: Primer on epoxy question
Post by: The Antipodean on December 30, 2009, 02:01:21 am
I used an automotive spray/filler primer in a spray can on my tug and it held tight, the acrylics crazed and never fully set up on it.

I am sure the old pros here can give better advice though.
Title: Re: Primer on epoxy question
Post by: Peter Fitness on December 30, 2009, 02:49:14 am
I may be old, but I'm not a pro  :-) , however, I use an acrylic primer/filler over epoxy resin with good results. I rub the epoxy down well with wet and dry to give a good key, and the paint adheres well.

Peter.
Title: Re: Primer on epoxy question
Post by: The Antipodean on December 30, 2009, 02:51:38 am
I would guess my crazing would be because I didn't sand enough.
Title: Re: Primer on epoxy question
Post by: boatmadman on December 30, 2009, 08:58:11 am
I have used car rattle can primer on epoxy many times with no problems.

 :-))
Title: Re: Primer on epoxy question
Post by: tigertiger on December 30, 2009, 01:47:46 pm
Cheers chaps  :-))
Title: Re: Primer on epoxy question
Post by: Bunkerbarge on January 02, 2010, 10:59:23 pm
Some epoxy resins contain a wax that rises to the surface to exclude oxygen to enable the curing process.  I know there are many out there with a more comprehensive explanation than that but the result is that you can have a waxy residue left on the surface of the resin.  Crazing is a classic effect if you don't deal with this wax as the paint 'floats' on the wax.

You need to thoroughly degrease with something like thinners and preferably give a good key by a rubbing down with wet and dry before using the rattle cans.  If you do that the paint should adhere perfectly well.