I know, I know… Not another Posca bleed thread, sorry guys.
Tried the archives, but my searches must be weak. Looking for a definitive list of Posca pen colors and their bleeding traits under the Gloss coat (poly resin).
I have a really special Coke Bottle green resin tinted longboard and I did my signature and serial # with a fine tip Purple Posca. The purple bled just slightly under the gloss coat and made me sick. I was trying to pick up the purple in the fin and resin pinlines and thought the Posca would work fine.
I have another yellow resin tinted longboard I was planning on using Poscas to accent some resin work, but now I’m a bit leary of acrylic pens. The work on the Yellow board is to be done with black and white Poscas.
Thought about lightly sealing with a spray bomb clear acrylic, but I see some have had bad luck with that method.
I've never had any good luck with pens. I stick to either india ink, water based acrylic paint, or resin for all work on top of a hot coat. What I've found out that in the "green tree hugger" rush to make all these pens "sniff / huffing proof...save the ozone, recycle, all electric pens" they have lost some of there "good qualities" that make them useful to surfboards.
So if you do use them, make sure your gloss is set off pretty quick. The longer the resin has a chance disolve any paint, or penline, the bigger your chance for failure. If the gloss takes longer than let's say 10 minutes to kick your asking for some kind of trouble. Also over brushing will scrub away the pinlines....Everybody like to keep walking around the rails with a paint brush for that final once over...right..around ,and around, and around..Fricking race track or what? I try to run the rail line once..maybe twice..then walk away. Keeping the gloss fairly thin helps this too...I always have a "no slab off" policy in my garage. If theres something funky like a bug or a wobble in the gloss it sands out pretty fast. Better to sand out a spot here and there, than have to sand the entire rail line and do a do over.
And when all else fails..do a test panel first. lay down some pen and scrub at it with resin and brush.
I’ve done some free hand artsy-fartsy stuff on the sanded hot coat with solvent based metallic paint pens.
Solvent based inks always REALLY react with gloss resin (or lam resin for that matter).
By sealing/encapsulating it with a good coat of artist acrylic Matte Medium like Liquitex or Novacolor, I avoid the reaction.
This will also work with posca pens since you are essentially creating a non penetrable barrier between the ink and the resin.
The best way to apply the Matte Medium is to spray on a couple of coats with an airbrush or a spray gun, let it dry, and then light sand it with some 320 grit or a scotch brite pad.
But hey, if you’re going to go with the trouble of spray painting, you might as well nix the posca pens and just spray the pinlines on with acrylic paint.
I use an artists acrylic matt varnish that comes in aerosol cans for my pinlines, or signatures on the gloss. Works a treat, and doesn’t react with the resin, or paint. I just do my pen work, hit it with a heat gun, and immediately give it a dusting with the acrylic. Just a dusting mind you, not a thick coat. Leave to dry completely or heat gun it. Then a very soft wipe with scotch brite, and gloss…bingo!
I’ve even used spray paint - lots of great colors! - for pin lines this way, and it hasn’t been an issue. I reckon the key is a LIGHT touch with the sealer, and the resin key into the acrylic…
I think the stuff Royal an I are taking about are the essentially same thing. Matte medium/ Matte varnish. It’s the clear binder that found in water based artist acrylic thats used as a mixing mediium or a final coat for a painting.
