# mixing polyurethane/clear coat sealers into paint??



## squiggles

HI, hope someone can help me. i was told some time back that you can mix polyurethane's into latex paint and have the item painted and sealed for a nice hard suffice all in one job.. is this true? our son wants his bedroom floor painted with gray porch paint but at 12 we want to make sure it has a good hard finish that will hold up to the traffic and abuse that kids dish out. If it can be done with polyurethane or varnish how many parts of paint to the other should be used?... thanks
squiggles


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## slickshift

No
Don't do that
Do not mix urethane into your paint

As for applying urethane _over_ porch paint, trust me, a quality porch paint is way harder than polyurethane, or polyurethane mixed into paint
After all, it's meant to be walked on, right?

Also:
It seems there is a lot of misconception about putting urethane over paint for like cabinets and railings and such making it more durable
I'd like to take the time to mention here it's simply not true
The proper coating alone will be much more durable than a urethane over coating
The only time a urethane coating makes sense is over bare or stained wood


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## Nestor_Kelebay

Squiggles:

You can not mix an alkyd based polyurethane (like a polyurethane hardwood floor finish) into a latex paint. You'll simply ruin both products. Latex paints form films through a completely different process than oil based products, and mixing them together simply won't result in anything good.

For a durable floor paint, you want to go with an alkyd or polyurethane floor paint. That is, an oil based floor paint, not a latex "Porch & Floor Enamel". The latter are just not hard enough to provide good service on a floor.

Essentially, the only difference between a polyurethane hardwood floor finish and a polyurethane floor paint is that the paint has pigments in it to give it colour and opacity. Both will dry to an equally hard finish.

You could also use an alkyd floor paint, and top coat with a polyurethane hardwood floor finish.

All "oil based" products, whether they be drying oils like linseed oil or Tung oil, or alkyd paints or polyurethane paints and varnishes all cure through a process called "auto-oxidation" whereby oxygen from the air is absorbed into the oil film and cross links all of the unsaturated sites together causing the oil film to turn into a hard solid. Consequently, if you do use an alkyd based floor paint instead of a polyurethane floor paint, you could paint over the alkyd with a polyurethane hardwood floor finish for extra durability. As long as you paint over that alkyd with the polyurethane within 24 hours (and I would do it as soon as you can walk on the alkyd paint) you should get good crosslinking between the two coats for excellent adhesion of the polyurethane to the alkyd floor paint. Similarily, you can also paint over a polyurethane floor paint with a polyurethane hardwood floor finish to make for a thicker film, and therefore a more durable coating on your floor. The important thing is to apply each coat within 24 hours (and preferably less) of the previous coat to ensure good crosslinking betwee coats so that they all stick well to each other.

Basically, polyurethane resins are really nothing more than alkyd resins with urethane groups inside them. If you want to know more about the chemistry of making alkyd resins, and the chemistry of modifying that process to produce polyurethane resins, post again.


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## squiggles

Nestor_Kelebay, slickshift, 
Thank you both for your help. One reason i asked it just didn't sound right to me. So glad i asked for help first. Going to go get a better paint for his floor. Thanks for stopping me from making a huge mess and the added expensive you save us.
squiggles


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## Nestor_Kelebay

No problem, Squiggles.

You're not likely going to get a more durable paint in a "user friendly" format than an alkyd based polyurethane floor paint. Even an alkyd floor paint should provide good service on a floor.

There are much more durable floor paints, but they're much less user friendly, like two component epoxy floor paints and moisture cure or two component isocyanate based polyurethane coatings. The epoxy is probably the more user friendly of the bunch.


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## squiggles

:laughing: new wrinkle.. son thinks he wants camouflage painted on floor now, guess there is some more thinking to do.


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## BillyD

Just remember when he out grows his wants you have to refinish or carpet the floor.


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## slickshift

Lol.....kewl on the camo floor
:thumbsup:


Actually, that wouldn't be that hard to do
Pick three (or even two might work OK) colors from the 'camo'
Using latex paint, base color the floor
Color wash color #1 (latex paint and glaze mix)
He could even help...faux is really fun
Color wash color #2 (latex paint and glaze mix)
Top coat with....in this case, two or more coats acrylic (latex) floor polyurethane

True, the latex poly will not hold up as long as oil poly, but if you keep up on it (re-coat before it splits and lifts), it can last until he's long grown out of it

Just be sure to practice on some test subjects first


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## squiggles

thanks for the information... we are looking forward to painting the floor. Son said oh rats i will have to sleep on couch for days.. he already sleeps on couch most of the time ..:laughing: so no complaints there. but now hubby wants to wait till school starts before we start on his room. but i will take pic when done and post it if i can figure out how. Squiggles


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## ukdiyer

I recently painted my floors (the house I moved into had painted floors in bad shape) with a porch and floor latex paint and used a water-based polyurethane. It was fairly easy and so far so good.


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## Harpmaker

Please forgive me for bringing up an old thread here, but I do have a similar question; is there any reason not to mix water-based polyurethane (Minwax Polycrylic Satin) with latex house paint or artist acrylic paints? All these paints are 'water-based', but coming from a woodworking background it just doesn't seem right to mix poly and latex. BTW, the reason to add the Satin Polycrylic to the latex paint is to supposedly give the mix more gloss and to make it level out better when rolled on a wall than the latex paint alone. These mixes are to be used as a DIY screen for a front projector.

A second, but related, question is would adding a water-based artist arylic 'clear medium' to latex paint cause any foreseeable problems? I would guess not, but I would like to check with those on this forum that know about paint chemistry and such. :thumbsup:


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## hammerheart14

you can only mix polyurethane with stains. water with water, oil with oil. NEVER MIX IT INTO PAINTS THOUGH!!!!


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## Harpmaker

hammerheart14 said:


> you can only mix polyurethane with stains. water with water, oil with oil. NEVER MIX IT INTO PAINTS THOUGH!!!!


Thank you for the quick reply, but can you be more specific why not to mix water-based poly with regular latex paint, both being water-based?


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## hammerheart14

Harpmaker said:


> Thank you for the quick reply, but can you be more specific why not to mix water-based poly with regular latex paint, both being water-based?


just because two products are water based, doesn't mean you can mix them together!!! you cant mix primer with paint. two different chemical compisitions. poly is meant as a clear finish over wood, paint is made as a solid skin, so to speak. besides, why not just use a semi gloss or gloss paint. enamel paints will have the hardness of poly and their shine too.


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## Harpmaker

hammerheart14 said:


> just because two products are water based, doesn't mean you can mix them together!!! you cant mix primer with paint. two different chemical compisitions. poly is meant as a clear finish over wood, paint is made as a solid skin, so to speak. besides, why not just use a semi gloss or gloss paint. enamel paints will have the hardness of poly and their shine too.


Again thank you for the reply. There is a popular DIY Screen forum that advocates mixing gray flat latex paint and satin water-based poly (up to 30% poly by volume!) to get a mix that has more gloss than the flat latex alone, but less gloss than a satin, or perhaps even eggshell, gray latex. Also they believe they can control the gloss of the mix by varying the amount of poly added. While people seem to be doing this without problems it always struck me as being the wrong thing to do. As you say, poly and paint, even if both are water-based, are different compositions. Thank you for verifying that I was not thinking amiss.

If there are any paint chemists on the forum, I would like to know more about what happens when different water-based "finishes" are combined. I see that Nestor_Kelebay hasn't been on this forum for almost a year... nuts; it sounds like he might have been able to enlighten me in this respect.


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## racebum

the only way i know of to put a urethane finish on a pigment paint is to heavily prime the wood with auto primer builder, shoot automotive base coat, then the clear coat. no home finishes i have found work this way. i have used auto paints on wood before and with the right prep work it works, very durable too.


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## kctyphoon

*check your facts*

one of the main things i hate about fourms, is that people always try to pass off "opinion" as "fact". i stumbled across this thread and had to join just to comment. i was looking for an answer to the same question. 

i have no idea how old this thread is - but concerning the question on if you can mix water based poly with laytex paint - apparently you can - quite easliy and with good results. as a matter of fact, the company " Turbine Products" makes a turbine sprayer that can be used to spray latex paint that is thinned out. now guess what they are using to help thin it out??? they even have a "how-to" video on youtube showing exactly how they want customers to thin out latex paint before using it in their sprayer. they use a mix of - conditioner - and WATER BASED POLY to thin out the latex paint before being sprayed in their sprayer. here is the address to the video - see for yourself - http://www.youtube.com/watch?v=VTEIo0RRFKw

if you give someone advice - please know what you are talking about. what you "think" doesnt justify it as "fact":whistling2:


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## Harpmaker

Thanks for the video link kctyphoon, I now remember seeing this before and my jaw dropping in wonderment that a spray gun manufacturer would advise such a thing. His final paint mix consisted of 4 oz. of latex paint and 3 oz. of clear medium (1 oz. Floetrol and 2 oz. water-based poly). While the presenter never said such in the video the poly he used was "satin" and not a high gloss.

No offense, but I don't consider a spray gun manufacturer's recommendation to mix water-based poly with latex paint to thin it enough to spray as being "proof" it is truly a good thing to do. It just means it won't hurt the gun.


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## jschaben

Harpmaker said:


> Thanks for the video link kctyphoon, I now remember seeing this before and my jaw dropping in wonderment that a spray gun manufacturer would advise such a thing. His final paint mix consisted of 4 oz. of latex paint and 3 oz. of clear medium (1 oz. Floetrol and 2 oz. water-based poly). While the presenter never said such in the video the poly he used was "satin" and not a high gloss.
> 
> No offense, but I don't consider a spray gun manufacturer's recommendation to mix water-based poly with latex paint to thin it enough to spray as being "proof" it is truly a good thing to do. It just means it won't hurt the gun.


I suspect what the presenter was trying to do was bring the sheen back to the latex. 25% mix of Floetrol can affect the sheen of latex paint. Reference Flood Corporation website concerning Floetrol. I personally don't see any issues mixing water based with water products, I did have to smile when he wanted the poly well shaken though. I also don't see any benefits adding poly to good quality latex. Also, despite the fact he was present what looked to me like about a $700 HVLP system, I've sprayed latex with my much cheaper Earlex with about half the concentration of Floetrol and no poly. :thumbup:


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## Harpmaker

jschaben said:


> I suspect what the presenter was trying to do was bring the sheen back to the latex. 25% mix of Floetrol can affect the sheen of latex paint. Reference Flood Corporation website concerning Floetrol.


In my very limited experience with Floetrol it dries to a clear, but hazy, flat/matte finish by itself, so if it were added to the maximum recommended limit of 25% of the mix I guess it could decrease the gloss of a latex paint. Rather than adding a water-based satin polyurethane I think I would rather add more of the same paint, but in a higher gloss to compensate for any gloss lost via the Floetrol.

One thing I can say is that Minwax Polycrylic will yellow over time (6 months to a year), but perhaps not to the point where people would notice for normal decorative uses (we tested it in DIY screen mixes).



> I personally don't see any issues mixing water based with water products,


Maybe, maybe not; that is why I posted the question here in hopes that a paint chemist might shed some light on the subject. :thumbsup:



> I did have to smile when he wanted the poly well shaken though.


I meant to mention that as well, but forgot. As most here probably know, the flattening agent in many paints and clear finishes is powdered silica. If the container of finish sets for some time the silica can fall to the bottom and must be stirred back into suspension. Just a few shakes of the container like the guy did in the video isn't really enough to reliably do that unless it was stirred properly in the recent past.



> I also don't see any benefits adding poly to good quality latex. Also, despite the fact he was present what looked to me like about a $700 HVLP system, I've sprayed latex with my much cheaper Earlex with about half the concentration of Floetrol and no poly. :thumbup:


Those that I know of that are adding water-based poly to latex paint claim that it helps roll the paint without leaving roller marks. While that may be so (but I have my doubts) there is a better way to achieve that; using Floetrol comes to mind. 

I would have to watch the video again to be sure, but I think the system used sells for $449.00 which is too rich for my blood. If I was going to buy a turbine HVLP system I think I would go with the inexpensive Earlex. It has nozzles and needles made from metal instead of plastic and they can be had in a number of different sizes for spraying different materials.

I have sprayed latex paints through my cheap Harbor Freight compressor-powered HVLP gun with no problem, but I did thin them with between 20% and 30% distilled water. I want to rapidly point out that this was not for "normal" painting (like interior walls or furniture), but to make DIY front projection screens.


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## Windows

kctyphoon said:


> one of the main things i hate about fourms, is that people always try to pass off "opinion" as "fact". i stumbled across this thread and had to join just to comment. i was looking for an answer to the same question.
> 
> i have no idea how old this thread is - but concerning the question on if you can mix water based poly with laytex paint - apparently you can - quite easliy and with good results. as a matter of fact, the company " Turbine Products" makes a turbine sprayer that can be used to spray latex paint that is thinned out. now guess what they are using to help thin it out??? they even have a "how-to" video on youtube showing exactly how they want customers to thin out latex paint before using it in their sprayer. they use a mix of - conditioner - and WATER BASED POLY to thin out the latex paint before being sprayed in their sprayer. here is the address to the video - see for yourself - http://www.youtube.com/watch?v=VTEIo0RRFKw
> 
> if you give someone advice - please know what you are talking about. what you "think" doesnt justify it as "fact":whistling2:


We are very lucky to have an _expert_ like you who has the experience of 1 watched Youtube video to teach us both about paint chemistry and forum etiquette. Thank you sensei!


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## hammerheart14

kctyphoon said:


> one of the main things i hate about fourms, is that people always try to pass off "opinion" as "fact". i stumbled across this thread and had to join just to comment. i was looking for an answer to the same question.
> 
> i have no idea how old this thread is - but concerning the question on if you can mix water based poly with laytex paint - apparently you can - quite easliy and with good results. as a matter of fact, the company " Turbine Products" makes a turbine sprayer that can be used to spray latex paint that is thinned out. now guess what they are using to help thin it out??? they even have a "how-to" video on youtube showing exactly how they want customers to thin out latex paint before using it in their sprayer. they use a mix of - conditioner - and WATER BASED POLY to thin out the latex paint before being sprayed in their sprayer. here is the address to the video - see for yourself - http://www.youtube.com/watch?v=VTEIo0RRFKw
> 
> if you give someone advice - please know what you are talking about. what you "think" doesnt justify it as "fact":whistling2:


I have been selling paint and applying it for fourteen years, I DO KNOw what I am talking about. Obviously, it is you that people should be careful of. I have meet SEVERAL chemists in my lifetime, and all the newer, higher quality acrylics are NOT TO BE MESSED WITH!!! I even asked if P&L accolade can be thinned with a paint conditioner added, and the chemist said all that he recommended was to add 5% water (6 ounces)!!!! If the product is not URETHANE FORTIFIED, THEN DO NOT ADD AN ACRYLIC URETHANE TO IT!!! BUY an acrylic urethane coating. There's a reason why these chemists are hired in the first place, and paid good money to come up with good products!


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## Harpmaker

hammerheart14 said:


> If the product is not URETHANE FORTIFIED, THEN DO NOT ADD AN ACRYLIC URETHANE TO IT!!! BUY an acrylic urethane coating. There's a reason why these chemists are hired in the first place, and paid good money to come up with good products!


Most excellent point! This leads to another question that while being a bit off-topic for this thread is related to it. If the mods or admins think this question should be in a new thread please delete this post and I will repost as a new thread.

Question: is it safe to mix different brands of latex paint together? If not, what happens?


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## hammerheart14

Harpmaker said:


> Most excellent point! This leads to another question that while being a bit off-topic for this thread is related to it. If the mods or admins think this question should be in a new thread please delete this post and I will repost as a new thread.
> 
> Question: is it safe to mix different brands of latex paint together? If not, what happens?


If it's the same type of product, sure. For instance, if you had one gallon of Pratt and Lambert Accolade exterior eggshell and mixed that with Ben Moore Aura exterior low lustre, then it would be no problem and just fine. But ON THE OTHER HAND, if you had Pratt and Lambert Accolade Exterior Eggshell and mixed it with a cheap paint like Glidden's Evermore exterior satin, you're wasting your money by mixing a high quality paint like Accolade with junk like Glidden. Just like if a junkie mixed peruvian blue cocaine with dirty crystal meth. get the point?


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## Harpmaker

Yep, got the point; but that brings up the "quality" of latex paints which is another mystery to me. What makes P&L and BM so much better than Glidden and Behr? I know it's the quality of ingredients, but just what does that mean?


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## hammerheart14

Harpmaker said:


> Yep, got the point; but that brings up the "quality" of latex paints which is another mystery to me. What makes P&L and BM so much better than Glidden and Behr? I know it's the quality of ingredients, but just what does that mean?


Better paints, like P&L and BM's higher quality lines, have better resins, more solids, and better binders in the paint itself, along with higher quality colorants. They are willing to spend more money for the better ingredients. If you try, say, P&L Accolade paint against behr's ultra premium, you'll notice how much better a paint, like accolade is.


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## carpecanic

I came across this thread some time ago and since that time I have added water based poly to latex paint. these mixtures have been applied to children's furniture cabinetry and signs for the most part. I have mixed Ben Moore with Minwax polycrylic, verathane floor finish, zinsser floor finish and oil modified minwax polyurethane. I have also used Sherwin Williams duration , Martin Senour ,and even Valspar (the economy stuff from Lowes). 
So far I have mixed 1 part poly to 4 parts paint as well as 1 part paint to 4 parts poly. thinned with 10% water and 1.5 oz Floetrol per quart for spraying. 
So far I have found this method to produce a ridiculously hard and durable finish. Especially when using the floor finishes. using the Ben Moore Cottonballs white with the verathane poly after 1 weeks time you can hardly even machine sand it off.
I have a design studio in Charleston South Carolina. What led me to ultimately try this was needing very bright and vibrant colors that were already latex paint colors. it was becoming tedious to color match these in the solvent based lacquers that we traditionally have been using.
I have personally used this method on over 220 pieces since first reading this thread with great success. The only thing I cannot offer is several years wait time to see how these finishes have held up.

I thought it prudent to come back and add my experience just the same. For the next person like myself that may read this thread, I hope this helps. Good day.

Nicholas


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## carpecanic

*****************************

I tried to post a pic for an example but I guess it was not permitted. I also forgot to mention that the poly mixture lays down on Machined MDF without any prep to seal it up before hand. This is true for the ultra light MDF as well but it requires a few more coats. Hope this is helpful.


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## dm1337

I just wanted to add my own 2 cents to this conversation. I am currently experimenting with this technique as well. I shoot with HVLP. I'm just done applying 2 coats of Target Coatings EM9000 gloss poly mixed with 40% EM6500 lacquer. This mix shoots and levels like a dream. It cures quite quickly as well. It sands beautifully. The only thing I find lacking is hide, since obviously there is only 40% color added. I plan on trying a 1:1 mix next and see how well that shoots. 

It appears to me that those who discourage this practice haven't tried it and rely on second hand information to pass judgement. It's quite easy to try it yourself, which is what I've done. So far the results are good. And I'm quite glad to hear that other people have had success as well. To me that sounds like a 100% success rate for those who've actually tried it.

Also, in the car painting world, it is not uncommon to see 1 stage paint made by mixing base with clear coat. I know those are specifically tested to be compatible together, but I don't understand the reluctance from some of the posters. It looks to me like a case of "I ain't seen it before so it must be bad".


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## ParoGirl

*Successful project mixing latex and water based poly 15 years ago*

I happily and perhaps ignorantly mixed latex paint into water-based poly - 1 part latex with 8 parts poly - for a whitewashed pine beadboard ceiling. Ignorant of the chemistry, so just tried it to make sure it would dry without tackiness and get the look I was after. Still looks great after about 15 years. I'm about to do it again to give a certain rubbed, tumbled sheen to a faux stone floor in my basement. We'll see how that holds up. Maybe I'll post again in 15 years, Lord willing! :001_tongue:


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## Matthewt1970

Looks like this thread is on a 2 year cycle


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