# Priming MDF



## AVLPainter (Dec 16, 2014)

I've got a job coming up where I need to paint bare MDF. I've never done MDF before. I got a scrap piece and sanded both sides smooth, about 150 grit. Then I put Kilz 2 primer on it. Interestingly, one side stayed smooth with the primer, but the other side is very rough after the primer. Can't figure out why there would be a difference, but it's very distinct. I would like to avoid sanding after priming (except on routed edges, which I believe is unavoidable). I want to use waterborne primer.

The rough side on my test board is REALLY rough - we're not talking a little fuzzy, we're talking serious bumps. Does anyone have a good process for MDF?


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## Sustainable in OR. (Dec 30, 2010)

*MDF Primer*

Benjamin Moore 217 Enamel Under body primer.


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## TJ Paint (Jun 18, 2009)

Kilz 2? 

That stuff is worse than a generic flat paint.


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## Brian C (Oct 8, 2011)

how can any professional painter not have experience with mdf ?


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## PremierPaintingMa (Nov 30, 2014)

AVLPainter said:


> I've got a job coming up where I need to paint bare MDF. I've never done MDF before. I got a scrap piece and sanded both sides smooth, about 150 grit. Then I put Kilz 2 primer on it. Interestingly, one side stayed smooth with the primer, but the other side is very rough after the primer. Can't figure out why there would be a difference, but it's very distinct. I would like to avoid sanding after priming (except on routed edges, which I believe is unavoidable). I want to use waterborne primer.
> 
> The rough side on my test board is REALLY rough - we're not talking a little fuzzy, we're talking serious bumps. Does anyone have a good process for MDF?


BM 217 Enamel Under body primer, make sure you get the edges.
It sand nicely too.


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## misterpaintguy (Aug 20, 2013)

It's not really necessary to belittle people who ask questions is it? Just say, " BM 217 and move on.


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## phillyholiday (Jun 5, 2014)

Kinda out of the box but we have been priming with lacquer undercoater on large unprimed MDF panels and finishing with SW pre-cat wb epoxy. The pic is of the pre-cat over crap pre-primed MDF baseboard.


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## Brian C (Oct 8, 2011)

misterpaintguy said:


> It's not really necessary to belittle people who ask questions is it? Just say, " BM 217 and move on.


Really ? Sorry man, but any pro painter that asks a question like this is not a professional painter.


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## PRC (Aug 28, 2014)

Brian C said:


> how can any professional painter not have experience with mdf ?


I have only worked with it once in 17 years. In my market they only use real wood.


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## journeymanPainter (Feb 26, 2014)

Brian C said:


> Really ? Sorry man, but any pro painter that asks a question like this is not a professional painter.


Been in the industry for +11 years. I don't think I've ever come across un primed MDF, that being said I still know how I would approach this.


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## AVLPainter (Dec 16, 2014)

Thanks for the info on the BM and the lacquer undercoater. I'll give those a try. 

Interestingly, I thought discussion forums were for learning things we don't know, and sharing our expertise in a particular area with others who run into something they haven't done before. In fact, I just posted a comment for a guy who's never tried using a vibrating sander for drywall repair, and wanted some info on it. I've been doing it for years. And I didn't have to belittle him in the process.

My experience in life with people who think they know everything, is that they are the ones who don't.


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## Bender (Aug 10, 2008)

....


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## Lambrecht (Feb 8, 2010)

If you want to stay with water borne or based try Aqua Lock available at Benjamin Moore.


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## Oden (Feb 8, 2012)

Brian C said:


> Really ? Sorry man, but any pro painter that asks a question like this is not a professional painter.


Eeeh C'mom now
Different guys do different kinds of work and for years
I can easily imagine a repaint guy never running into raw MDF. 

'Professional' means you get paid to. That is all the word means. Get paid to paint anything and ur a professional painter. Anything-not everything,


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## Bender (Aug 10, 2008)

Brian C said:


> Really ? Sorry man, but any pro painter that asks a question like this is not a professional painter.


I got your back Bri


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## Bender (Aug 10, 2008)

Oden said:


> Eeeh C'mom now
> Different guys do different kinds of work and for years
> I can easily imagine a repaint guy never running into raw MDF.
> 
> 'Professional' means you get paid to. That is all the word means. Get paid to paint anything and ur a professional painter. Anything-not everything,


From Wiki...
*Trades*

In narrow usage, not all expertise is considered a profession. Although sometimes referred to as professions, occupations such as skilled construction and maintenance work are more generally thought of as trades or crafts. The completion of an apprenticeship is generally associated with skilled labor or trades such as carpenter, electrician, mason, painter, plumber and other similar occupations. A related distinction would be that a professional does mainly mental work, as opposed to engaging in physical work.


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## Gough (Nov 24, 2010)

Professional: (of a person) engaged in a specified activity as one's main paid occupation rather than as a pastime.
"a professional boxer"
synonyms:	paid, salaried
"a professional rugby player"


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## Bender (Aug 10, 2008)

A *professional* is a member of a profession. _The term also describes the standards of education and training that prepare members of the profession with the particular knowledge and skills necessary to perform the role of that profession._


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## Bender (Aug 10, 2008)

In addition, most professionals are subject to strict codes of conduct enshrining rigorous ethical and moral obligations.


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## Bender (Aug 10, 2008)

Professional standards of practice and ethics for a particular field are typically agreed upon and maintained through widely recognized professional associations.


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## Bender (Aug 10, 2008)

I would like to avoid sanding after priming as well, but I'm sorry, its unprofessional.


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## Bender (Aug 10, 2008)

AVLPainter said:


> Interestingly, I thought discussion forums were for learning things we don't know, and sharing our expertise in a particular area with others who run into something they haven't done before.


Also, I don't disagree with this AVL.

I like SW water based undercoater, but for the life of me I cant think of what its called.


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## MKap (Sep 11, 2010)

Brian C said:


> how can any professional painter not have experience with mdf ?


Because professional carpenters do not use MDF.


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## Gough (Nov 24, 2010)

Bender said:


> Professional standards of practice and ethics for a particular field are typically agreed upon and maintained through widely recognized professional associations.


So you're saying that there's no such thing as a professional painter?

I think the normal distinction in its adjectival use is professional versus amateur.


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## Brian C (Oct 8, 2011)

I must admit I assumed you lot were familiar with mdf as its used exclusively on interior trims down here. I apologise for my ignorance.


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## Gough (Nov 24, 2010)

Brian C said:


> I must admit I assumed you lot were familiar with mdf as its used exclusively on interior trims down here. I apologise for my ignorance.


Around here, Brian, we typically only encounter it pre-primed.

The only time we've encountered the raw version is in furniture or casegoods that we've built and finished in house.


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## Damon T (Nov 22, 2008)

I've seen it in various instances. Sheet panels ripped down for example.


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## Steve Richards (Dec 31, 2010)

Trial and error, Google, or the old guy at the paint store..but never ask a question on PT.


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## Mustache Paul (Jan 11, 2015)

Hello, BIN white shellac,, sands out quickly with 320 without binding up the paper inside of six hours. Seals well excluding MDF edges that needs two coats. Anything water based pops the grains quite badly and usually if your using MDF on built ins you're really looking for a smooth finish. Regards


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## CobraCDN (Jan 8, 2008)

Most of our closet shelving up here for new construction, we build out of MDF. I've had great results with simply 2 coating them with our eggshell wall finish. I use Cloverdale's Super II Eggshell Latex. It will require a lite sand between coats, only place the fibres raise will be on the edges. Usually coat them the same color as the closet walls , means no cutting for the wall cleats.


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## Krittterkare (Jul 12, 2013)

Yea most new shelving I do is unprimed MDF and most any water primer or even flat paint is fine and with it sanding and dusting is necessary but it sands easily and an orbital or palm sander makes quick work of it.


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## CobraCDN (Jan 8, 2008)

phillyholiday said:


> Kinda out of the box but we have been priming with lacquer undercoater on large unprimed MDF panels and finishing with SW pre-cat wb epoxy. The pic is of the pre-cat over crap pre-primed MDF baseboard.
> View attachment 31561



So I'm curious, having never used any of the WB epoxys. How is their comparability with your wall finish coats? Can it be touched up or recoated by hand after? What's the advantage of using the WB epoxy over just your favorite semi-gloss latex?


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## Joseph (Aug 26, 2013)

I usually go over mdf or any particle board with oil primer then finish with latex. Always turns out great 


https://www.calgarypropainting.com
https://www.calgarypropainting.com/blog/index.php


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## TJ Paint (Jun 18, 2009)

Steve Richards said:


> Trial and error, Google, or the old guy at the paint store..but never ask a question on PT.


Especially if you actually need an answer!


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