Best Paint for Acrylic

[Ernie Martinez]

I need to make a painted sign out of acrylic which I will be producing on the CNC machine. My question is what paint/primer should I be using that will stand up to the elements, and will adhere to acrylic.

Thanks

[Paul Phillips]

Ernie, I'm sure you'll get 100 different opinions on this so I'll just tell you what we use. For cheap/easy, 1-shot sign enamel will be fine, most sign supply stores and even some automotive paint stores will have it. You can get plastic primer spray can from Lowes/HD for small jobs or automotive grade primer will usually work fine if you have spray equipment to do it yourself. We specialize in high-end custom architectural signage so we need the best which is IMHO Matthews Paint which is a catalyzed urethane based automotive quality paint that lasts for years outside, also for any high production sign shop, you can get a paint mixing station and access to their online database of color formulas, for instance, you have a customer that wants to match a Benjamin Moore latex color, you just look up the formula for that color and mix the matthews to match, I'm sure you've seen a similar system to what they have at any paint store or Lowes/HD. The only drawback is the price to get started is about $2g, but that gets you the mixing station for free, you just pay for the initial paint supply. Most sign supply stores sell it also. http://www.ppg.com/coatings/matthews...s/default.aspx
Hope this helps.
Paul

[Joe Pelonio]

There really isn't anything like One-Shot, but it is expensive and many colors still contain lead. For indoor jobs I will use rattle-can plastic primer, then spray acrylic latex with the HVLP gun. Many times I have to mix custom colors and often can do so with leftover paints that I have in the shop. For outdoors I will try to get away with Krylon or Rustoleum after the primer but if there is a color match I will spray automotive for big jobs, for small still use acrylic latex but than use a clear topcoat by One-Shot over it.

[Ernie Martinez]

Thanks Guys!

[Balsanu Gabi]

Hi,

Interested on this area (dont want to steal this thread), but I have a wuestion regarding painting acrylic. How do you avoid cracking acrylic?

Thanks
Gb

[Mike Null]

Many have this problem with extruded acrylic and find it wise to use an acrylic paint. With cast I use Rustoleum painters touch or Dutch Boy acrylics.

[Paul Phillips]

Balsanu,
From my experience the cracking, also referred to as "crazing" is usually caused by paint that has an aggressive solvent in it such as lacquer, this can be solved by using a water based primer first and then using the solvent based paint over that, however that usually means you also have to scuff or sand the acrylic first so the primer has better adhesion. Also any of the paints that Joe and Mike suggested will work as well. You should always do a test piece first to see how well it will work. Also, take care how you clean the Acrylic before you paint as solvent based cleaners such as Denatured Alcohol can cause the crazing as well, a water based cleaner or just soap and water will work fine for cleaning before paint.
Paul

[Ernie Martinez]

I found a Krylon product called "Krylon for Plastic" at Lowes. Will see how that works.

[Ernie Martinez]

Correction, the product I found was Valspar for Plastic. Doesn't work on Acrylic, I'm peeling off the paint just weeding mask out of letters with my fingernails, feels gummy. Will try One Shot next. I'm assuming that this stuff is durable?

[Paul Phillips]

Ernie,
not sure about the Valspar primer because I've never used it, I've heard good things about the Krylon Fusion brand though like Joe said. 1-shot is an excellent paint, it's formulated for the sign industry it's been around for 60+years and is what most of the old school hand lettering sign painters used to use before computer cut vinyl letters took over. We still use it on occasion to roll a background color on a duraply sign.
Paul

[Ernie Martinez]

I didn't use primer, I just sprayed onto the bare acrylic.

[Tucker Alford]

I learned the hard way about painting acrylic sheets. Our project involved masking 4x8x.75 acrylic masked with vinyl in the reverse. After cutting hundreds of names in vinyl, weeding & then transfering of names we proceeded to paint with off the shelf spray paint. After drying we began to removed the names in vinyl to expose the clear text only to find the paint didn't adhear properly & pulled up at the edges ruining the project. Take two, involved testing every available local product ending with Krylon Fusion. The stuff is amazing & requires no primer, good for when you want to paint in reverse. I found the best selection of colors available at Walmart.

[Ernie Martinez]

Did you sand the acrylic first or did it adhere to a smooth surface?

[Tucker Alford]

Peeled the factory brown paper mask, applied my vinyl & paint. No crazing, excelent durability & resistance to lifting when using a mask.