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leverne99 06-04-2009 10:51 AM

Painting wood finished trim white...
 
We just bought a house that is older and outdated with wood stained trim and doors throughout. We want to paint all the existing wood trim and doors white. I've read that we need to use an oil based primer, is this true? Also, what grit do I use to sand with first and can we leave the trim up or do we need to take it down??? Please help!!!!!!!

NAV 06-04-2009 04:30 PM

I would not use an oil based primer on wood trim. Oil dries hard and if you hit the trim with something that could dent it the paint will chip.

I know a lot of people will disagree with me but here is what you should do:

1) sand the trim with 100 - 120 grit sandpaper to remove all sheen. wipe it down with a solution of TSP and water or if you think there is not contaminants on it use some tack rags or mineral spirits.

2) Prime with a latex bonding primer - Sherwin Williams Bonding Primer works well. Make sure the can reads Bonding Primer not just Prep-Right

3) if there are areas that stains blead through you should spot prime with an oil stain blocking primer.

4) finish with 2 to 3 coats of high quality interior semi-gloss or satin.

Good luck - I would never paint over stained woodwork unless it is pine.

Matthewt1970 06-04-2009 06:37 PM

Wrong. Oil based primer is the absolute best thing you can prime unpainted wood with.

"3) if there are areas that stains blead through you should spot prime with an oil stain blocking primer."

A lot of times you will not see some of the wood bleed till weeks or months after you prime and paint. Prime it with oil based primer the first time and then you won't have to worry about any wood bleed.

Scuba_Dave 06-04-2009 07:54 PM

I paint everything w/oil based primer
Works great

NAV 06-05-2009 06:39 AM

Matthewt1970

Like i said I am sure there will people that disagree but to say i am wrong is ignorant.

Its not 1980, latex has come a long way. If you live in California, Ohio, Illinois, Indiana, Michigan, and a few other states Oil is not even an option for painting inside your house. there are strict VOC laws (Volatile Organic Compounds).

That being said; take you oil primer and put it on glass. then take Sherwin-Williams Bonding Primer and put it on glass. you oil will fail an adhesion test and the latex bonding primer will not.

On top of the adhesion difference (that may be helpful when painting over a smooth coating like polyurethane) Latex is pliable and will bend with impact wile oil cracks and chips.

next time do some research before you tell someone that knows much more than you they are wrong.

leverne99 06-05-2009 08:29 AM

Thank you! I think I will follow your advice and not used oil based.

waynech 06-05-2009 09:01 AM

NAV
My concern with using a latex primer would be bleed through. I have seen it many times in the past where someone has spent a lot of hours of prep and paint to only see all the the trim have bleed through. This can take awhile to reveal itself. In this partcular case I would sand trim with 150 or 220, wipe with wilbond, caulk and putty, prime with oilbase, sand with 220 and then finish coat with a quality latex trim paint. That's my 2 cents.
I understand that everyone has there own system. However, some are better than others. I have tried both of these systems and found the one that I described to work the best for me.
P.S How do you know that you know more than him.

NAV 06-05-2009 09:19 AM

because I know everything!!!!

Leverne what state do you live in. this may end the debate of the best process.

sirwired 06-05-2009 07:43 PM

While I use water-base bonding primer on a current oil-base coat, I would hesitate to use it on unpainted wood.

SirWired

Matthewt1970 06-06-2009 12:56 AM

Quote:

Originally Posted by NAV (Post 283079)
Matthewt1970

Like i said I am sure there will people that disagree but to say i am wrong is ignorant.

Its not 1980, latex has come a long way. If you live in California, Ohio, Illinois, Indiana, Michigan, and a few other states Oil is not even an option for painting inside your house. there are strict VOC laws (Volatile Organic Compounds).

That being said; take you oil primer and put it on glass. then take Sherwin-Williams Bonding Primer and put it on glass. you oil will fail an adhesion test and the latex bonding primer will not.

On top of the adhesion difference (that may be helpful when painting over a smooth coating like polyurethane) Latex is pliable and will bend with impact wile oil cracks and chips.

next time do some research before you tell someone that knows much more than you they are wrong.

LOL, Laughable. First off, we are not talking about glass. Latex Primer will NOT beat oil in bonding. 2nd, Latex primers DO NOT block wood tannins worth a darn. I just saw it happen last summer with some brand new Zinsser Bullseye Latex Primer. My father primed the underside of a staircase with it. The next moring it was all yellow and brown. After a coat of Oil Coverstain it was good to go. You even mentioned it in your first post to put oil based primer on it if the wood bleeds. Why would you need oil if latex is so much better?

I have oil based primer on the woodwork in my house and there are plenty of dings in it and they aren't all chipped.

Now we can move on to the issue that Latex Primer will also lift the grain of the wood and most times not go back down to normal once dry making what was a nice smooth surface nice and rough.

As far as knowing so much more than me, I guess you haven't seen latex primer fail much, but you will.

clintb 06-06-2009 01:17 PM

Oil based primer, such as Zinsser Coverstain, or even better, BIN (but that's shellac based with alcohol as the solvent).

slickshift 06-06-2009 05:37 PM

Quote:

Originally Posted by leverne99 (Post 282656)
We just bought a house that is older and outdated with wood stained trim and doors throughout. We want to paint all the existing wood trim and doors white. I've read that we need to use an oil based primer, is this true? Also, what grit do I use to sand with first and can we leave the trim up or do we need to take it down??? Please help!!!!!!!

Although there are acrylic primers that claim to be for this use, and some may even work, the best choice is a solvent-based primer (alcohol/alkyd) for two important reasons:

1) The stuff on their now is either oil-based, or at best unknown (most likely that or possibly some other solvent-based product)
For these cases a solvent-based works best (adhesion)

And even if it might be water-based:
2) The stuff on there now is most likely at least medium dark
For these cases a solvent-based primer is preferred to hold back the darker color and keep it from bleeding through (not something you want to see a week or two after all your hard work)

I'd recommend a light scuff sanding (not to remove what's on there, only to give the primer some "tooth"), cleaning (tack cloth, vacuum, or Swiffer), and a coat of Zinsser's Cover-Stain or similar (...Zinsser's BIN is also an excellent choice, but more "aromatic" and sloppier to apply...but my first choice for real questionable surfaces or real dark stains)
Then top-coat either water/solvent as your druthers, but something of quality that dries very hard (like a waterborne enamel, like Ben Moore's Impervo or Sherwin Williams Pro Classic)

If I absolutely could not use a solvent-based primer, my next choice would a water-based bonding primer from Insl-X or UMA
The process would be the same as described above

Scuba_Dave 06-06-2009 07:31 PM

Quote:

Originally Posted by NAV (Post 283079)
That being said; take you oil primer and put it on glass. then take Sherwin-Williams Bonding Primer and put it on glass. you oil will fail an adhesion test and the latex bonding primer will not.

I generally don't paint the window glass
or at least try no too :laughing:


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