Primer for alumalite white?

[Nufo]

I am using createx paints and epoxy topcoats. Any recommendations on a good primer that will bond well to the resin and createx? I also plan to start playing with some alumifoam so any suggestions for a primer for that are welcome as well.

Thank you
Mike Profumo

[dahlberg]

Just make sure the blanks are clean and oil free and no primer is needed. Also, don't forget, you can dye the base resin any color you wish.
best
L

[aka anglinarcher]

Alumifoam appears to me to be hydrophobic (repels water). Because of this, if you thin your water based paints too much, it beads. If you use Createx and you don't thin it, and you don't put too much on for a first coat, then it works as a primer. I usually shoot un-thinned white Createx at 40 psi with a medium needle. I have plans to test other ideas, but have not had time yet.

For Alumilite White, Larry is dead on (as always). Still, I find it is best to not thin the base coat too much.

None of the paints will adhere to the point you cannot scratch them off with even a finger nail. That is really not a problem. If you top coat with an epoxy or something like EnviroTec, then it forms a super strong protective cover that even Pike and Muskie teeth cannot penetrate.

I have been trying a product used for taxidermy called PolyTransPar, super hide white. Even if you don't thin it, it beads on both the Alumilite White and Alumifoam. I advise that if you experiment with other paints that you don't buy too much of it to start with. Still, if I just mist the first two coats, I still get an excellent result.

I hope this helps you, but for now, follow Larry's advise for the Alumilite White. When you jump to the Alumifoam, just use the Createx and don't thin the first coat, keeping the coat thin.

[aka anglinarcher]

I lost my MoJo while working on other lures, so I came back to the question. A lot of people have asked this question before, so I thought it might be fun to do some observations with possible primers. This is not scientific, so if you have different results, let us know.

I called WASCO and for their fiberglass molds they sell a lacquer based primer. Of course, this takes some time to dry and you cannot use it inside without a vent hood, mask, etc. I did consider it, but I just don't want to go down that road. Their Tec suggested that I might try a polyurethane. He said that with the fiberglass, it is a problem with the super slick finish. I believe that this is part of the "issue" with the foam and the white.

I had semi-gloss polyurethane (clear), a Krylon satin finish spray acrylic, and a can of black Krylon Fusion. For those that are interested, "Fusion" is suppose to bond to all plastics. I sprayed test samples of the AL White and Alumifoam and let them dry overnight. Note that the Fusion is dry in 15 minutes and the other two seemed to be dry in less than a half hour, but I wanted to give a fair test.

Alumifoam --

I sprayed the Polytranspar superhide white on a test sample without a primer. As expected, it looked like it beaded. Upon a closer look under a magnifier, Alumifoam skins over, but there are high and low spots as the bubbles expand. Without a primer, the high spots shed the wet paint and it migrated to the low spots, appearing to bead. I added a few drops of Isopropyl Alcohol to a batch of paint to see if that would smooth it out but it made it worse. I tried glycerin as well, but it had no change other than to slow down the drying.

Next I sprayed the superhide white on each of the "primer" samples. I let it dry about 10 minutes then gave it a good heating with a heat gun. I then checked out the results.

Krylon Fusion - The black sure showed off the high and low spots, but it all covered without beading. The superhide covered very well without beading. Nevertheless, I would not suggest white over black in normal practice. It was much harder to scratch the paint off the foam with the fusion, but it was still possible to scratch it off with a fingernail.

Krylon Acrylic - The superhide white covered very well, again without beading. It was much harder to scratch off the paint, even harder than with the Fusion. Still, it could be scratched off.

Min Wax Polyurethane - The superhide white covered very well, also without beading. It was almost as hard as the acrylic to scratch the paint off, but as before it was still possible.

Summary, if you don't mind using a solvent based primer, the Krylon Acrylic and the Min Wax Polyurethane made for great coverage, improved adhesion, but a premium top coat is still needed. None of the tested materials would build up enough to even consider them for a top coat. The Krylon Fusion was better than no primer, but it was not my favorite.

Alumilite White --

I had no need to test the White with any additive, so I just went to the Superhide White over the primers. All primers covered extremely easy and showed no sign of beading.

Krylon Fusion - After spraying with the superhide white and drying per the above procedure, I could not scratch the paint off with my fingernail. A sharp object could scratch the finish with some work.

Krylon Acrylic - Again, I could not scratch the paint off with my fingernail. It took about the same amount of work as the Fusion to scratch with the sharp object.

Min Wax Polyurethane - See above, same results.

Summary, if you don't mind using a solvent based primer, then all three made for great coverage, improved adhesion, but a premium top coat is still needed. None of the tested materials would build up enough to even consider them for a top coat.

Conclusion:

If a primer is desired, I would probably get the Krylon Acrylic. I would spray lightly outside so I did not need a hood. I would then take inside to dry in a dust free area. Because most, if not all, of our airbrush painting is with water based paint, it will adhere well to the acrylic because it is also acrylic.

For the Alumilite White, if you keep it clean and free of oils, you probably don't need a primer if you use Createx. If you feel a need to improve adhesion, you can lightly sand the lure before painting to roughen it up, or wipe it with acetone to soften and clean the plastic. Still, if you have a lot of surface detail you are trying to protect, the Acrylic primer would work well. For the Alumifoam, a light sanding opens the pours and you can get some better adhesion as well. I don't suggest the acetone for the foam. The acrylic would sure add options to improving paint adhesion.

Cover the above paint jobs with Enviro Tec or Devcon 2 Ton and they should last a life time.

[Mike - Alumilite]

One other note to add ... IF you can paint/prime the piece soon after demolding while the resin or Alumifoam is still "curing" you will get some chemical adhesion between the paint and the urethanes which will greatly enhance the adhesion characteristics of the paint. Paint lays on top, dries, and sticks but doesn't truly bond. Best thing is to spray your silicone mold with your base color, allow it to completely dry, then cast your piece. The Alumilite resins will chemically bond to the paint and you will demold a painted piece. If this isn't an option, try to clean as Larry suggested and hit it with the base coats that AA suggests as soon as you can after demolding to improve the adhesion.

Mike