# Painting over varnish



## BigDogPainting

I am bidding an interior paint project. Customer has wood trim and knotty pine walls in two hallways and a staircase connecting the two hallways. All wood has a coat of varnish. My plan is to scuff the varnish with 220, apply one coat of primer, and two top coats of paint. Will the scuffing work or do I need to completely strip the varnish from the door casings, doors, and walls? Could tsp take the place of the sanding?


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## diamondback22

*painting over varnish*

Hello, I have painted over varnish many times.. Never really had any trouble..it does want to "flash" if you try to skip the primer coat. I would sand it well a then clean it with the TSP..your 3 coat system should work well..good luck...


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## CliffK

Scuff sanding is never a bad idea when adhesion is a concern. Many times though,a good bonding primer can do the work of scuff sanding. My concern would be more to make sure it's reasonably clean. Many times these type of surfaces have gone many, many years without being addressed and the grime can really build up and no one sees it, therefore no one ever cleans it. Even the bonding primers need a clean surface. I would not suggest to strip the varnish as long as it is sound. I would think stripping would not be cost effective in most instances and usually unnecessary.


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## jack pauhl

Always a good idea to use Krud Kutter in a spray bottle to clean everything to remove any household cleaner products, Pledge etc. Pay attention to areas that are handled often around door knobs etc.

Use xylene instead of thinner, turpentine or other oily cleaners should you need a solvent for anything.

I'd scuff it up pretty good. Look at it this way... sand first so after your coat of paint is on -- you wont do battle trying to sand something out of an acrylic that may or may not be easy to sand. Wet sanding helps with some acrylics.


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## sagebrush123

I would sand also, just top break the gloss shine build up...gives a nice tooth, even for the primer...and then clean it well.....and get a great adhesion primer. and if you have doubt...just sample a small area and check with a scratch from the nail after it has dried.

You never know WTF was used for previous coatings......and it is better to be safe than sorry.

would not think it necessary to strip any of it...overkill...nor using something as strong as XIM as it is tough to work with smell and too soupy/watery.

do report back with your findings and process....


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## RPS

I would scuff it with something more aggresive like 120. Then rub it down with deglosser or wilbond. Screw the tsp.


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## Dbo

I just did a job like this a week ago where the HO had bought all the material and paint. She just never got around to doing it and wanted it done. She had a deglosser and behr primer and paint semi-gloss. Never had been a fan of behr paint especially for walls so I was a little hesitant to use it on varnished trim. I wiped all the trim down with the deglosser and paint the trim with two coats. It turned out great and was really impressed with it. No sanding or prime coat and it had a nice enamel finish that was durable. This was a newer home and don't think I would try this on an older home. Older trim is different and needs to be primed and sealed so it won't yellow.

In the past I would have lightly sanded, used a primer like Bullseye and two coats of semi-gloss. Saved me time and the HO money from doing a extra coat. Guess you can teach an old dog new tricks!


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## Faron79

I'm NOT a fan of deglossers.

Waaaayyyy too heavy on fumes and VOC's. JEEZ I hate this stuff....even the principle of it!!

A couple minutes of sanding will yield a much better surface, with "tooth", than a temporarily tacked-up surface with HIGH solvent-load deglossers.
To the "very occasional user"/DIY, any benefit of a deglosser is gone within a half-hr. So, if your job gets interrupted, you've just dumped a huge load of solvents into your air for NO benefit. If continuing with deglossing, it must be re-applied...so another load of solvents/fumes...for only a temporary benefit.

Unless you're dealing with Lead-infused substrates, sanding is totally non-toxic. Plus...."Muscle-shirt" season is here, isn't it....:blink:?!?!

Faron


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## jack pauhl

Faron, Its amazing how many people dont know that. I think your 30 minute time is a bit inflated though.  Its really much quicker. More like degloss a casing, paint a casing, degloss some base, paint some base. Very counterproductive.


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## StevenH

I would use 150-180 grit for the primer to adhere.


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## RPS

I said sand and degloss. Or even laquer thinner. dull the surface and get any build up of waxes or grease off the surface.


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## valuepro

I followed a quote last year, where a painter quoted to just spray two coats of white semi gloss over top. Told the home owner they didn't need to sand it. Funny, he wasn't going to charge GST and wanted 50% up front. hmmm wonder if he got the job or not.


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## mastr

you could do:

- sand, white pigmented schellac primer, topcoat
or
- use adhesion primer and skip the sanding part


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## RPS

Don't skip the sanded part. Ever.


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## BigDogPainting

valuepro said:


> I followed a quote last year, where a painter quoted to just spray two coats of white semi gloss over top. Told the home owner they didn't need to sand it. Funny, he wasn't going to charge GST and wanted 50% up front. hmmm wonder if he got the job or not.


Wasn't going to charge GST? Whats GST?


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## bobhart

*Varnish?*

Did I miss something or am I just too old here? I was always told to use (and I do) denatured alcohol to cut and remove varnish. I removed a ton of varnish from a 1930ish home that had all it's trim of chestnut varnished and then a coat of clear poly looks great.


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## PaintSlave

I'd Xim that knotty pine if its that old school wall board stuff.. Clean it bond it paint it, i wouldnt even run a sanding block down it.


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## BrushJockey

bobhart said:


> Did I miss something or am I just too old here? I was always told to use (and I do) denatured alcohol to cut and remove varnish. I removed a ton of varnish from a 1930ish home that had all it's trim of chestnut varnished and then a coat of clear poly looks great.


Too old I guess ( lol) If you used denatured, you removed a shellac coat, not varnish. DNA won't do a thing on an oil varnish.


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## Ccmpainting

BigDogPainting said:


> I am bidding an interior paint project. Customer has wood trim and knotty pine walls in two hallways and a staircase connecting the two hallways. All wood has a coat of varnish. My plan is to scuff the varnish with 220, apply one coat of primer, and two top coats of paint. Will the scuffing work or do I need to completely strip the varnish from the door casings, doors, and walls? Could tsp take the place of the sanding?


You not only have to worry about adhesion you ha e to worry about bleed thru. Lightly sand and use coverstain oil primer. Let it dry at least 24 hours before topcoating with your choice of latex paint.


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