Primers for Thermofoil Doors

Advice on a good base coat for an adhesion layer between Thermofoil doors and a paint topcoat. February 12, 2010

If possible, what would the procedure be for painting thermofoil cabinet doors? I'm remodeling a kitchen and my customer is interested in changing the color of her doors and drawer fronts.

Forum Responses
(Finishing Forum)
From contributor L:
In the past I have sanded off the gloss and played with a primer that adheres well, and finished as usual. I think I used Zinsser shellac.

From contributor T:
For painting plastic automotive parts, you would clean, lightly scuff with UF 3M pads and then apply a product like Bulldog adhesion promoter. The stuff works great. It's available at auto body supply shops.

From contributor L:
I am assuming the thermofoil doors you are talking about are an almost vinyl material on a one piece MDF door? Not plastic automotive parts? If so, again I would go with a Zinsser primer and test it. Let the primer dry and check how well it adheres. It bonds to almost anything and is a great primer for almost any topcoat as well. If it is plastic automotive parts, then never mind.

From contributor K:
Yes, they are thermoplastic over MDF cabinet doors. I've considered using Zinsser Bin, XIM, and SW PrepRite bonding primer as primers. As usual, a test panel is in order.

From contributor T:
Composites are plastics. Vinyls are also plastics, auto or not. What harsher test is there than exterior automotive coatings? Let's not "play with primers that adhere well" when the technology is already available. Bulldog or any other brand of this type of product is designed for galvanized metal, vinyl, chrome, fiberglass, aluminum and glass. I do not know whether or not it's compatible with the top coating you use, but from the hot sun of Arizona to the cold winters of Minnesota, I know how I'm coating composites in harsh environments.

From contributor A:
While I respect contributor T's auto experience, he is going nuclear on this project. The cost may be prohibitive and completely unnecessary.

I actually agree with contributor L's BIN suggestion. The great thing about shellac is it sticks to everything and everything sticks to it. I would either start with BIN or go directly to a high quality waterborne pigmented topcoat. The waterborne products typically have better adhesion than solvent products when applied to non-porous substrates. Acrylic paint sticks to glass like the big time.

From contributor R:
That Bulldog stuff looks pretty good - I'll check it out.

The smartest thing you can do is try several different things and do your own adhesion test to see what really works and what doesn't. That way you can show your client why you use the products you use.

From the original questioner:
Looks like I have some good options and that the project is doable. That's what I wanted to know. Thanks!