Hi all, we finally have some good eps foam here in the UK and I'm going to shape up a 12'6". I have shaped a lot of boards in the 70's - 80's out of PU and polyester.
My question is do you guys ever spray color directly onto the foam and what paint do you use. I understand that it puts a layer between the foam and lamination but its been normal practice over the years and would like to know what you think..cheers SD
You can only buy Nova Color directly from them, they don’t sell it in stores. That keeps the price of their paint down. Acrylic Gesso is essentially white acrylic paint with calcium carbonate added to it as a filler. I don’t think that there’s that much difference in brands of gesso except in price. All art supplies are notorious for being extremely over priced in retail stores. You can use a good quality flat exterior acrylic white to mix your slurry. In another thread about painting EPS, Surfding has been using Kilz primer sealer.
Depending on the density of the foam and how it finish sands, you will likely want to mask the stringer, squeegee some light weight spackle compound over the surface, and fine sand before spraying.
I have used microballoons mixed with white acrylic paint and distilled water for a home made slurry that worked fine as a spackle/sealer. There are a couple of commercially available brands in the US but I'm not sure what you have over there.
For paint, I have used basic tempera poster paint mixed with acrylic floor finish and distilled water. There are commercially available water based acrylics that are used by some. Shooting a clear coat of the acrylic floor finish over the color helps protect it during glassing process.
Dab each color to some scrap material, let dry, and test with your resin to make sure.
The slurry can be epoxy mixed with microballoons and a little white pigment (more work to sand) or a waterbased white acrylic mixed with light weight spackle (way easier to sand).
The paint can be any water based paint as long as it has in it - or you add to it - a good acrylic binder like Matte medium ,Future floor shine.
My preference is:
NovaColor Acrylic Gesso mixed with Fast 'n Final Spackle and water for the slurry.
Nova Color Acrylics for the paint.
3m 232 tape for taping curves and 3m 2209 tape for taping over color.
The weave of the fiberglass tends to show more over darker colors.
Hey guys, thanks for your replies, they are so much help.
Tris Cokes here in the UK at Homeblown supplies eps blanks that shape and finish near to PU blanks apparently.
You guys also seem to favour spackling the blank everytime, the guys here don't seem to on their surfboards but I will as it makes sense to get a finer finish, we have micro balloon fillers and the like so should'nt be a problem and I will do some test pieces on scrap foam first though and easy sanding is fine by me!
I know it may not meet with approval but although I've surfed for 39 years now I'm also into sup and we dont have any board factory that wants to shape and make race/downwind boards and I need a downwinder and also we have limited if any at all downwind and distance boards other than expensive Naish or Starboards which in my opinion are not quite always hitting the mark in design to much yet so custom has to be the way to go.
Atomized, your boards are fantastic, Seabase (Boardworks) here make for Stewart (or did) are you polishing the epoxy as we would polyester, sandcoat/sand / gloss coat / wet n dry/polish etc or speedcote?
Thanks again guys and thanks for the welcome....SD
what grit do you sand the epoxy hotcoats to make sure the PE gloss will not fall off over time?
Surferden-
I do PE hotcoats over Epoxy lamination , when I do that , I spackle only with epoxy+microbaloon slurry ( thin - honey)
as it seals the blank better than the light spackle found at the hardware stores. necessary so the PE doesn't burn the blank! ( don't even ask how I know that)
regarding spary paints/airbrush work over eps- it never looks as goog as if it was on PU .
even after spackle !! the eps beads get a lighter tone than the gaps between them ( filled gaps!!) which go darker.
also happens with tints. I you wanna end up with a beautifull EPS boards go for a pigmented Lam.
I can verify that microballoons or Fast/Final, etc can be mixed with white acrylic paint like KILZ to make a good sealer/primer. If the final primed/sealed blank is smooth enough, the painted surface under the glass is hard to distinguish from polyurethane foam.
It doesn't sand quite the same as when thinned with distilled water but close. I use a medium grit drywall screen on upholstery foam for my final sanding of the sealed blank. The color was sprayed on. I would have used something finer if I planned to do a tinted lamination.
If you followed the recent thread on the prone paddleboard project, he used Fast and Final thinned with alcohol and really liked how fast it dried.
What did you use to paint your board? It looks nice and crisp. Resin pins over sanded fillcoat?
Don’t need to. I’ll paint clear (matte medium) in transparent fades on areas that the color fade out to zero to make sure the color has something to stick to. For example on this board, after the black line work was painted, a transparent blue fade was shot in from the rails. I first shot clear over the center of the board for the blue to stick to. By using transparents the black shows thru the color.
