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aggressively thinning latex paint?

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Ether Jones

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Aug 23, 2006, 8:04:16 PM8/23/06
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Is it OK to aggressively thin latex paint with distilled water? My
aim in doing so is NOT to increase coverage, but rather to improve the
penetration into splits and cracks and rough areas. My intent would
be to allow this first thinned coat to soak in and dry thoroughly, then
apply two more coats of the same product, unthinned.

If the answer is "no", could you please give some technical explanation
why it is not a good idea.

I already tried this on some old treated pine deck boards I used to
repair portions of an exterior porch stairs. I washed and rinsed the
boards, then let them dry thoroughly. Then I painted them with an
exterior acrylic latex porch paint thinned 50/50 with distilled water.
This first coat had remarkable penetration. After it dried
thoroughly (a couple of days in 85 degree weather in the garage) I put
2 more coats of the same product, unthinned, allowing thorough drying
between coats. I used these boards to replace some worn exterior
porch stair treads, but they've only been in place for a couple of
weeks so far so I won't know the results for a couple of years.

In the past, I've used an oil primer, followed by 2 coats of latex
topcoat, but haven't had very good results. The latex bonded
tenaciously to the primer, but the primer blistered and peeled away
from the wood. This exterior application sees lots of sun, rain,
snow, and foot traffic.

bob kater

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Aug 23, 2006, 9:22:58 PM8/23/06
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oil base paint dosen't breathe so any moisture will lift the paint. latex
does so some moisture will come through without any issues. I have used
floetrol (sp) available at DD Lowes, and sherwin williams to thin it and
extend drying time (on Latex) which lets it penetrate more and although some
paints do not reccomend it I have not had a problem. Penetrol is for oil
based paints but not as easy to find
"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1156377856.6...@i42g2000cwa.googlegroups.com...

Richard J Kinch

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Aug 24, 2006, 1:15:29 AM8/24/06
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Ether Jones writes:

> Is it OK to aggressively thin latex paint with distilled water?

Isn't that ordinarily done with sprayers?

George E. Cawthon

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Aug 24, 2006, 2:33:19 AM8/24/06
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Thinning aggressively is a bad practice, you may
get the color to move into cracks but you end up
with mostly pigment and very little base to hold
the pigment to the wood. If you look at most
latex primers it says to not thin or to use a
maximum of 10 percent thinning fluid. BTW,
thinning with distilled water is overkill, any
drinkable water would be acceptable.

Latex paints don't really penetrate, they just lie
on the surface. So your idea of penetrating doing
something good is false. Paint won't fill in
cracks effectively. What you want to do is lay on
a coat that cover thoroughly to seal the wood by
coating it. If there are cracks you should be
sealing the cracks with a caulk before you paint.
Or, preferably, use sound board with no cracks.

A really good undercoat that dries on your hands
takes a lot of work to get it off, even if you
skin is oily. Your thinned paint will come off
your hands relatively easily.

What you need for a long lasting application is
not aggressive thinning, but aggressive coating.
The wood needs to be smoothed, cracks filled, and
the surface coated with a high quality porch paint.

Ether Jones

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Aug 24, 2006, 9:14:42 AM8/24/06
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George E. Cawthon wrote:

> Thinning aggressively is a bad practice, you may
> get the color to move into cracks but you end up
> with mostly pigment and very little base to hold
> the pigment to the wood.

Thanks for your lengthy response George. Some of your comments puzzle
me so I'd like to ask a few questions.

I don't understand your statement that I "end up with mostly pigment
and very little base to hold the pigment to the wood". If I thin
50/50, doesn't the ratio of base to pigment stay the same? In other
words, what happens to all the base? Isn't it still there, just like
the pigment is? Or is there some sort of chemical reaction where the
water destroys the base? I realize that by thinning, I don't get as
thick a coat as I would otherwise, but I figure that "something" is
better than "nothing", since the unthinned paint simply does not get
down into the fine cracks in the wood.

The cracks I am talking about are not large cracks that could be
caulked. I'm talking about many fine splits in the wood; of the order
of the thickness of a piece of paper. The unthinned paint simply
cannot get in there thoroughly, no matter how aggressively I brush it.
And, as it cures it leaves pinholes where the splits are; pinholes
where water could get in. If I thin the paint 50/50, it's still
fairly thick, but it is able to soak down into the splits instead of
just bridging over them. Then when I let it dry and paint over it with
unthinned paint, I get a continuous coating with no pinholes.

I tried scraping and washing a portion of the porch floor, then letting
it dry thoroughly and painting it with 50/50 thinned latex. You can
see the paint soak in to the fine splits, and when it dries it
absolutely doesn't rub off - it is very tenecious. I intend to cover
this first thinned coat with 2 additional coats using unthinned latex.
I'm not trying to go cheap on paint; I'm trying to get the wood coated.
Also, there are nooks and crannies in the porch where it's very
difficult to get the unthinned paint to go; a prime example is between
the deck boards. If I use unthinned paint, it wants to "bridge over"
adjacent boards instead of soaking down between them. Then, when you
walk on the boards, the slight relative motion between adjacent boards
causes the paint "bridges" to fail and expose bare wood. If I paint
these areas with thinned paint, it penetrates between the boards and
coats the hidden edges (where water drips down through). In this case,
when putting the unthinned overcoats in these areas, I would be
carefull to brush out any paint bridges.

> If you look at most
> latex primers it says to not thin or to use a
> maximum of 10 percent thinning fluid

The label says "do not thin" but it does not say *why*. Since I
intend to thin only the first coat, and then go over it twice with
unthinned paint, I would like to understand if (and why) thinning is
still objectionable.

> Or, preferably, use sound board with no cracks.

I understand that this would be optimal. In another universe I'd love
to do that. But I don't have the time or money to rip up my porch
floor. I'm constrained to work with what I have, with the wood in
place. There is no rot, but in many areas the wood is weathered, and
the paint is blistering and peeling (actually, the latex topcoat is
adhering to the primer, but the oil primer is peeling from the wood).
It's because of my unsatisfactory experience with oil primer that I am
exploring other approaches.

> the surface coated with a high quality porch paint.

In the painful process of learning, I've had the "pleasure" of using
several different paints, some of them awful. The one I am using now,
and with which I am fairly impressed, is "Best Look Premium 100%
Acrylic Latex Satin Porch & Floor Enamel" from the local hardware/paint
store. It says on the fine print on the label that it's made by
Sherwin Williams. It costs about 25 bucks a gallon. It is very thick
and creamy, easy to apply, and coats very well.

Norminn

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Aug 24, 2006, 9:14:56 AM8/24/06
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clipped

> In the past, I've used an oil primer, followed by 2 coats of latex
> topcoat, but haven't had very good results. The latex bonded
> tenaciously to the primer, but the primer blistered and peeled away
> from the wood. This exterior application sees lots of sun, rain,
> snow, and foot traffic.
>

I think label instructions are good advice, and wouldn't recommend more
thinning than the label advises, especially for high wear and outdoors.
It might work, but why tempt fate for a tough condition? Primer should
not blister unless applied to damp or dirty wood or in hot, direct sun.

Start with clean, dry wood. Scrape and sand as needed. To fill cracks
(which invite disruption of paint film and intrusion of moisture), apply
paintable, flexible caulk after primer dries. Prime the caulk after it
dries. Paint. Cover all sides of the boards.

I don't buy cheap paint, and I hate paint prep work, but I am a fanatic
about the prep when I paint or paper because I don't want to have to do
it over. Why use poor quality paint, or ruin good quality paint? Paint
stores have product specifically for thinning both types of paint and
which don't weaken the film. The logic in not thinning too much is that
you dilute to the point that you are applying little more than colored
water. Of course, it would have "remarkable" penetration. Buy some new
wood or Trex.

Steve B

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Aug 24, 2006, 10:10:38 AM8/24/06
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I use a product called Floetrol for thinning Latex paints. It also adds a
lot of good properties like helping the paint flow. This is good for doors
when you want the paint to lay flat and not have brush marks. Available
most anywhere.

Steve


Ether Jones

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Aug 24, 2006, 10:50:45 AM8/24/06
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Norminn wrote:

> Paint stores have product specifically for thinning both types of paint and
> which don't weaken the film.

"doesn't weaken the film" is the part I want to understand better. Why
doesn't this product "weaken the film" but water does? I'm not saying
you're wrong, I just want to understand how it works.


> The logic in not thinning too much is that
> you dilute to the point that you are applying little more than colored
> water.

So... it doesn't matter if I thin the latex 50/50, as long as I apply
enough coats that the total amount of latex I use is the same as I
would have used if I didn't thin it?

For example, say I pour out two equal portions of unthinned latex into
separate containers. I paint one board with 2 coats using the first
portion (using it all up). I thin the second portion 50/50 with
distilled water, and paint the second board with that, applying coats
(and letting them dry) until the second portion is used up. Both
boards now have exactly the same amount of pigment and binder on them.
Will the paint on the second board fail because I thinned it? _Why_?
(It's the "why" part I am seeking to understand).

Steve B

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Aug 24, 2006, 11:03:29 AM8/24/06
to

"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1156431045.7...@p79g2000cwp.googlegroups.com...

>
> Norminn wrote:
>
>> Paint stores have product specifically for thinning both types of paint
>> and
>> which don't weaken the film.
>
> "doesn't weaken the film" is the part I want to understand better. Why
> doesn't this product "weaken the film" but water does? I'm not saying
> you're wrong, I just want to understand how it works.
>

Look at the two. The product is every bit as thick as latex paint. It has
the consistency of latex paint. It has the same polymers and surfactants as
latex paint. It has added polymers and surfactants to help the paint flow
and "skin" properly. Pour a cup of it in your hand. Watch what it does.
Feel it.

Now do the same with a cup of water.

Here's yer sign.

Steve


George E. Cawthon

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Aug 24, 2006, 4:52:55 PM8/24/06
to
Ether Jones wrote:
> George E. Cawthon wrote:
>
>> Thinning aggressively is a bad practice, you may
>> get the color to move into cracks but you end up
>> with mostly pigment and very little base to hold
>> the pigment to the wood.
>
> Thanks for your lengthy response George. Some of your comments puzzle
> me so I'd like to ask a few questions.
>
> I don't understand your statement that I "end up with mostly pigment
> and very little base to hold the pigment to the wood". If I thin
> 50/50, doesn't the ratio of base to pigment stay the same? In other
> words, what happens to all the base? Isn't it still there, just like
> the pigment is? Or is there some sort of chemical reaction where the
> water destroys the base? I realize that by thinning, I don't get as
> thick a coat as I would otherwise, but I figure that "something" is
> better than "nothing", since the unthinned paint simply does not get
> down into the fine cracks in the wood.

Sure the ratio is the same but the base needs to
be a certain concentration to provide a good a
reasonable coat, that is why manufacturers caution
against thinning. You don't need to get the paint
down in those thin cracks, you just need to be
sure that the paint seals over the cracks. I
suggest that you take a good board, and paint
small sections with 100%, 90%, 70%, 50% and 40%
paint thinning with water. Then scrub a dub with
water after 24 hours. That will show what the
paint you are using will do with thinning.

> The cracks I am talking about are not large cracks that could be
> caulked. I'm talking about many fine splits in the wood; of the order
> of the thickness of a piece of paper. The unthinned paint simply
> cannot get in there thoroughly, no matter how aggressively I brush it.
> And, as it cures it leaves pinholes where the splits are; pinholes
> where water could get in. If I thin the paint 50/50, it's still
> fairly thick, but it is able to soak down into the splits instead of
> just bridging over them. Then when I let it dry and paint over it with
> unthinned paint, I get a continuous coating with no pinholes.

If that is true then do it. However,you would be
much better off filling the cracks with something
other than paint, maybe glue thinned about 10
percent (use Elmers carpenter glue (the yellow
stuff). Not only will you have the cracks mostly
filled they will be glued together.

>
> I tried scraping and washing a portion of the porch floor, then letting
> it dry thoroughly and painting it with 50/50 thinned latex. You can
> see the paint soak in to the fine splits, and when it dries it
> absolutely doesn't rub off - it is very tenecious. I intend to cover
> this first thinned coat with 2 additional coats using unthinned latex.
> I'm not trying to go cheap on paint; I'm trying to get the wood coated.
> Also, there are nooks and crannies in the porch where it's very
> difficult to get the unthinned paint to go; a prime example is between
> the deck boards. If I use unthinned paint, it wants to "bridge over"
> adjacent boards instead of soaking down between them. Then, when you
> walk on the boards, the slight relative motion between adjacent boards
> causes the paint "bridges" to fail and expose bare wood. If I paint
> these areas with thinned paint, it penetrates between the boards and
> coats the hidden edges (where water drips down through). In this case,
> when putting the unthinned overcoats in these areas, I would be
> carefull to brush out any paint bridges.

You are trying to fix a structural problem with
paint. The board should not be moving in relation
to each other. If the boards are moving a tiny
bit you can seal with a flexible paint, but a
paint you walk on is not flexible to any extent.

>
>> If you look at most
>> latex primers it says to not thin or to use a
>> maximum of 10 percent thinning fluid
>
> The label says "do not thin" but it does not say *why*. Since I
> intend to thin only the first coat, and then go over it twice with
> unthinned paint, I would like to understand if (and why) thinning is
> still objectionable.
>
>> Or, preferably, use sound board with no cracks.
>
> I understand that this would be optimal. In another universe I'd love
> to do that. But I don't have the time or money to rip up my porch
> floor. I'm constrained to work with what I have, with the wood in
> place. There is no rot, but in many areas the wood is weathered, and
> the paint is blistering and peeling (actually, the latex topcoat is
> adhering to the primer, but the oil primer is peeling from the wood).
> It's because of my unsatisfactory experience with oil primer that I am
> exploring other approaches.
>
>> the surface coated with a high quality porch paint.
>
> In the painful process of learning, I've had the "pleasure" of using
> several different paints, some of them awful. The one I am using now,
> and with which I am fairly impressed, is "Best Look Premium 100%
> Acrylic Latex Satin Porch & Floor Enamel" from the local hardware/paint
> store. It says on the fine print on the label that it's made by
> Sherwin Williams. It costs about 25 bucks a gallon. It is very thick
> and creamy, easy to apply, and coats very well.
>

Maybe you have the problem in hand. OTOH, the
peeling may be due to moisture absorption from
below, if the porch is over uncovered soil.

Ether Jones

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Aug 24, 2006, 5:04:23 PM8/24/06
to

Steve B wrote:

> Look at the two.

I just looked at a container of Floetrol today. Until now, I'd never
heard of it.

> The product is every bit as thick as latex paint.

Very cheap latex paint maybe. Floetrol is nowhere near as thick as the
latex paints I have been using.

> It has the same polymers and surfactants as latex paint. It has added polymers and surfactants to help the paint flow and "skin" properly.

How do you know this? The label on the container lists no ingredients.
The MSDS doesn't list any ingredients (it does say the boiling point
is 212F though). Where did you get your information?

> Pour a cup of it in your hand. Watch what it does.
> Feel it. Now do the same with a cup of water. Here's yer sign.

Do you personally find that to be a satisfying technical answer to the
question?

If I paint one board with 8 ounces of high quality latex paint, using
as many coats as it takes to use up the paint, and I paint a second
board with 8 ounces of the same high quality latex paint plus 2 ounces
of distilled water, again using as many coats as it takes to use up the
10 ounces of thinned paint, are you saying the second board has a
"weaker" film? And if so, _why_?

OT, just heard on the news - Pluto has been stripped of its planet
status.

Ether Jones

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Aug 24, 2006, 5:55:03 PM8/24/06
to

George E. Cawthon wrote:

> I suggest that you take a good board, and paint
> small sections with 100%, 90%, 70%, 50% and 40%
> paint thinning with water. Then scrub a dub with
> water after 24 hours. That will show what the
> paint you are using will do with thinning.

Good suggestion. I wasn't as scientific as you suggested with all the
different percentages, but I did run a "sanity" test before I committed
to using the thinned paint in my actual application.

I took a representative sample board and power-washed it to remove the
old blistering paint, then I let it dry and gave it a single coat of
aggressively thinned latex (I would guess 50/50 although I didn't
measure it). After letting it dry thoroughly I blasted it with the
power washer (1700 psi) and it didn't budge. So I figured, on that
basis, that using the thinned latex as a first coat, to be overcoated
with 2 coats of unthinned latex, was a reasonable thing to do. My
reason for posting here was to try to get some additional technical
reasons, if there are any, why the process I described is bad practice.
So far, to summarize what I am hearing, the gist of most of the
counter-arguments is that thinning the latex causes a thinner coat to
be applied, therefore resulting in a "weaker film". But no one so far
has suggested (at least not in clear language) that adding too much
water actually interferes with the paint's chemistry. Since I intend
to overcoat the first thinned coat with 2 coats of unthinned latex, it
seems to me that the "weakened film" argument is moot.

> you would be
> much better off filling the cracks with something
> other than paint, maybe glue thinned about 10
> percent (use Elmers carpenter glue (the yellow
> stuff). Not only will you have the cracks mostly
> filled they will be glued together.

This is very interesting because this is exactly the sort of thing I
wanted to do initially, because it seems to make so much sense, but I
couldn't find _anybody_ to confirm the idea, despite talking to
contractors and paint-store people. Is this really a viable approach??
Would Elmers be the right stuff to use, or might there be something
even better? It has to be water-based for this project. Is Elmer's
really paintable?

> You are trying to fix a structural problem with
> paint. The board should not be moving in relation
> to each other.

My deck, which I built myself with 5/4" deck boards on 2x10 joists 16"
on center sitting on doubled-up 2x12 beams 6' on center supported by
posts every 5' along the beam length, you could drive a tank on it and
it wouldn't budge.

The porch is a different story. It is certainly not built as sturdily
as I would have done it myself, but it's not unlike many decks I have
walked on. The boards DO move slightly relative to one another when
you step on an area between joists. This absolutely kills the paint if
there are "paint bridges" joining the boards, as I discovered the hard
way. So when I re-paint it, I plan to avoid paint bridges between
adjacent boards.

> peeling may be due to moisture absorption from
> below, if the porch is over uncovered soil.

Yes, it's over uncovered soil. It is going to be very interesting to
see what happens over time to the newly-refinished treads on the rear
stairs. I discussed this in a separate post in this thread. I used a
different process on each of the 11 treads and risers.

Norminn

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Aug 24, 2006, 7:56:28 PM8/24/06
to
Ether Jones wrote:
> Norminn wrote:
>
>
>>Paint stores have product specifically for thinning both types of paint and
>>which don't weaken the film.
>
>
> "doesn't weaken the film" is the part I want to understand better. Why
> doesn't this product "weaken the film" but water does? I'm not saying
> you're wrong, I just want to understand how it works.
>
>
Guess it contains the binder, so without as much heavy, ground up
pigment your paint will be as strong but with less pigment per volume.

Paint has three essential functional products (sometimes lots more
chemicals): pigment, binder, vehicle. Pigment is the color you want.
Usually ground up stuff. Binder is what holds it together when it is
dry. Vehicle is what makes it liquid enough to get from the can to the
brush to the surface, and makes it run out flat. The pigment, without
the binder (or thinned too much) would make it like milk of magnesia,
white dust on the siding :o)


>
>>The logic in not thinning too much is that
>>you dilute to the point that you are applying little more than colored
>>water.
>
>
> So... it doesn't matter if I thin the latex 50/50, as long as I apply
> enough coats that the total amount of latex I use is the same as I
> would have used if I didn't thin it?

Quality paint rarely needs thinning. To thin it too much is to weaken
it's ability to stay on securely.


>
> For example, say I pour out two equal portions of unthinned latex into
> separate containers. I paint one board with 2 coats using the first
> portion (using it all up). I thin the second portion 50/50 with
> distilled water, and paint the second board with that, applying coats
> (and letting them dry) until the second portion is used up. Both
> boards now have exactly the same amount of pigment and binder on them.
> Will the paint on the second board fail because I thinned it? _Why_?
> (It's the "why" part I am seeking to understand).
>

Well, try this: take four boards, each 12" wide by four feet long. Cut
them in one foot lengths. Lay the 16 pieces of cut boards in four rows
of four. Should cover 16 square feet. Now pick them up, throw away 8
of them. Use the remaining 8 pieces to cover the same area.

Your thinned paint has binder spread too thin, I'm thinking. Might work.

Here is a link to additives, Floetrol (water base paint) and Penetrol
(oil base). Penetrol is only one I have tried, for spraying. Works
beautifully.

http://www.o-geepaint.com/cgi-bin/FrameIt.cgi?url=http://www.floodco.com

Norminn

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Aug 24, 2006, 8:08:39 PM8/24/06
to
Ether Jones wrote:

> Steve B wrote:
>
>
>>Look at the two.
>
>
> I just looked at a container of Floetrol today. Until now, I'd never
> heard of it.
>
>
>>The product is every bit as thick as latex paint.
>
>
> Very cheap latex paint maybe. Floetrol is nowhere near as thick as the
> latex paints I have been using.
>
>
>>It has the same polymers and surfactants as latex paint. It has added polymers and surfactants to help the paint flow and "skin" properly.
>
>
> How do you know this? The label on the container lists no ingredients.
> The MSDS doesn't list any ingredients (it does say the boiling point
> is 212F though). Where did you get your information?

MSDS doesn't list the chemicals, but does say that it is 90% volatile.
The other 10% is magic potion :o)

Ether Jones

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Aug 24, 2006, 9:10:13 PM8/24/06
to

Norminn wrote:
> Quality paint rarely needs thinning. To thin it too much is to weaken
> it's ability to stay on securely.

The question on the table is, *why*. See further discussion below:

EtherJones wrote:
> > For example, say I pour out two equal portions of unthinned latex into
> > separate containers. I paint one board with 2 coats using the first
> > portion (using it all up). I thin the second portion 50/50 with
> > distilled water, and paint the second board with that, applying coats
> > (and letting them dry) until the second portion is used up. Both
> > boards now have exactly the same amount of pigment and binder on them.
> > Will the paint on the second board fail because I thinned it? _Why_?
> > (It's the "why" part I am seeking to understand).

Norminn wrote:
> Well, try this: take four boards, each 12" wide by four feet long. Cut
> them in one foot lengths. Lay the 16 pieces of cut boards in four rows
> of four. Should cover 16 square feet. Now pick them up, throw away 8
> of them. Use the remaining 8 pieces to cover the same area.

Your example is flawed; it is in no way analogous to what I wrote.
Please reread my example more carefully. In my example, there was no
binder "thrown away". Both boards have exactly the same amount of
binder (and pigment) on them. So what makes one "weaker" than the
other? Are you claiming that the added water somehow prevents the
binder from polymerizing properly? And if that is what you are
claiming, where did you learn this? Could you please cite some
technical references.

Ether Jones

unread,
Aug 24, 2006, 9:17:19 PM8/24/06
to

Norminn wrote:

> MSDS doesn't list the chemicals, but does say that it is 90% volatile.

... and the boiling point of that 90% is, guess what? 212 degrees F.
Does that number sound familiar?


> The other 10% is magic potion :o)

Apparently a tightly held secret? Steve B claims they're "polymers"
and surfactants. I wonder where he got that info. Seems weird that
they would put polymers in it. You'd think they'd use monomers, like
the original latex, so it would boost the binder.

Warren Block

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Aug 24, 2006, 9:21:02 PM8/24/06
to
Ether Jones <Ether...@yahoo.com> wrote:
>
> I took a representative sample board and power-washed it to remove the
> old blistering paint, then I let it dry and gave it a single coat of
> aggressively thinned latex (I would guess 50/50 although I didn't
> measure it). After letting it dry thoroughly I blasted it with the
> power washer (1700 psi) and it didn't budge. So I figured, on that
> basis, that using the thinned latex as a first coat, to be overcoated
> with 2 coats of unthinned latex, was a reasonable thing to do.

It sounds like you've invented primer. The unknown is how long it'll
last.

Why not just use a real primer? Oil-based primer should sink in better,
but even a latex primer will have a better chance of a long life. Both
can be topcoated with latex.

--
Warren Block * Rapid City, South Dakota * USA

Ether Jones

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Aug 24, 2006, 10:29:00 PM8/24/06
to

Warren Block wrote:
> Ether Jones <Ether...@yahoo.com> wrote:
> >
> > I took a representative sample board and power-washed it to remove the
> > old blistering paint, then I let it dry and gave it a single coat of
> > aggressively thinned latex (I would guess 50/50 although I didn't
> > measure it). After letting it dry thoroughly I blasted it with the
> > power washer (1700 psi) and it didn't budge. So I figured, on that
> > basis, that using the thinned latex as a first coat, to be overcoated
> > with 2 coats of unthinned latex, was a reasonable thing to do.
>
> It sounds like you've invented primer. The unknown is how long it'll
> last. Why not just use a real primer? ...even a latex primer will have

> a better chance of a long life.

How is latex primer chemically different from latex topcoat paint?
Does it have a different binder system than latex paint?


> Oil-based primer should sink in better,

Why not oil primer for this job? Here's why:

Many claim that oil-based primer penetrates better, but the caveat is
that the wood must be BONE DRY. The least bit of moisture appears to
greatly interfere with absorption and adherence. By contrast, latex
seems to be fairly forgiving: to apply latex, the wood can't be wet or
damp, but it doesn't have to be baked dry for a week. This is a
significant issue for this outdoor project, especially at this time of
year, when finding a whole week where there is no rain and the humidity
is low and there is no dew in the morning is next to impossible.

The area to be painted is a high-use area; it is a great inconvenience
to take it out of service. If I power-wash it, I have to keep traffic
off it until it dries or it will get dirty again. For oil primer, that
means a full week of dry weather after washing. If it rains, I have to
wait another week.

Once the wood is dry and the oil primer is applied, it takes several
days to dry properly so that it can be painted with latex. If it rains
during this period it seriously compromises the primer. All during
this period, the area must be off-limits to traffic.

Once the latex is applied, I need another 24 hours of dry weather or
the latex will be compromised.


On the other hand, if I use latex:

After power-washing, the wood is ready to accept a coat of latex within
24 to 48 hours. Within 4 hours I can apply a second coat. Within 24
hours it is rain-proof and ready for foot traffic. Done.


Besides the significant inconveniences of oil (as detailed above), my
experience will oil-based primer has been highly disappointing. See my
other posts in this same thread for more details, but here is the gist
of it. I tried using latex topcoat over oil primer previously and the
system failed within one year. The latex topcoat bonded to the oil
primer, but the oil primer started blistering and peeling away from the
wood in large chunks. I tried to follow all the rules. I do not know
if I somehow did something wrong, or if oil primer just isn't the right
solution for this particular application (exterior, wood, horizontal,
foot traffic, sun, rain, snow). Some boards were coated all six
sides, and some were coated on the top and ends only. All of them
failed prematurely.

Steve B

unread,
Aug 25, 2006, 12:03:44 AM8/25/06
to

"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1156453463....@p79g2000cwp.googlegroups.com...

Let me just say this. I have used it. I like it. It works for me. Your
mileage may vary. Use it or don't. It's as good a solution as any
proposed.

Surely as good as water. Maybe even a little better.

Steve


Norminn

unread,
Aug 25, 2006, 7:58:19 AM8/25/06
to

I thought my example was pretty good, to illustrate that the diluted
binder has fewer molecules to hang together and cover your wood. If you
want a treatise on paint chemistry, go find one. You obviously
understand factors that made your paint job fail, so why pursue methods
that aren't recommended? I do exterior painting in the fall, when
conditions are optimum for what I want to do. Dry, not too hot, not too
cold, and comfortable enough to do all the right prep work. Have
cleaned up lots of other people's sloppy work, so I consider that
valuable experience. Common sense serves better than intimate knowledge
of the chemical compounds, it seems.

Ether Jones

unread,
Aug 25, 2006, 8:51:17 AM8/25/06
to

The thinned latex has exactly the same total number of molecules of
binder as the unthinned latex. Read the example again. Adding water
does not reduce the number of binder molecules, it just increases the
number of molecules of water.

Because the second portion has additional water, it is thinner and
therefore more coats will need to be applied to use it all up. But
once it's all used up, you've applied the same total number of binder
molecules to the second board as you did to the first.

> If you want a treatise on paint chemistry, go find one.

I've been looking. Haven't found one yet.

> You obviously understand factors that made your paint job fail,
> so why pursue methods that aren't recommended?

Because I want to understand WHY they aren't recommended. I like to
understand why I'm doing what I'm doing. If the label on the paint can
says "Do not thin", I want to know why. By knowing "why", I can
determine under what circumstances it might actually be permissible,
even beneficial, to thin (even though the label says "no").


> Common sense serves better than intimate knowledge
> of the chemical compounds, it seems.

Common sense is good yes. But sometimes what passes for common sense
is a collection of urban legends and anecdotal experiences. That's why
it's good to ask "why". I'm not saying that's true in your case. You
seem to have some substantial experience.

Ether Jones

unread,
Aug 25, 2006, 9:11:47 AM8/25/06
to

A thought just occurred to me which might be germane to this
discussion. Perhaps someone familiar with how latex paint works could
comment.

My understanding is that latex paint binder consists of monomers in
water solution.

When you apply a coat of latex paint, and the water dries, the monomers
come out of solution and begin to bond together into polymers. This
bonding action forms the strong film. Once the polymers form, they are
no longer water-soluble. That's why the film is water resistant, even
though the original vehicle was water.

Now, what happens when you apply a second coat of latex? Obviously the
process repeats itself. BUT, in addition to bonding with EACH OTHER,
do the monomers in the second coat ALSO bond EQUALLY EFFECTIVELY with
the polymers in the first coat, to create one seamless film (assuming
the first coat was kept clean) ? Or, is the bonding between the
monomers of the second coat and the polymers of the first coat only
PARTIAL, so that what you get is two SEPARATE films which are bonded
together, but the bond BETWEEN the two coats is not as strong as the
bond WITHIN each coat?

If the latter is true, it would explain the difference between boards
one and two in the example I gave in an earlier post. The first and
second boards would have the exact same total film thickness, but the
first board would have fewer, thicker layers; and the second board
would have more, thinner, layers. What this means in practical terms
as far as the quality of the paint job is still arguable I suppose.

Norminn

unread,
Aug 25, 2006, 12:51:21 PM8/25/06
to
I don't know anthing about monomers and polymers. By your description,
thinning the paint too much with water keeps the molecules from bonding
because they are spread too far apart. Reason I used the cut boards
(molecules of paint binder) example - you can't cover the same area with
half the material, whether microscopic or macroscopic. Capiche?

The boards you refinished likely had some moisture in them, having been
washed two days before. Not washed, but without impermeable finish,
they would be damp from being outdoors. Boards fastened onto a deck,
without being finished on all sides, would hold moisture. So, when
finish is applied, sun hits the deck, the moisture expands and the paint
film blisters or cracks.

jeffc

unread,
Aug 25, 2006, 11:46:50 PM8/25/06
to

"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1156377856.6...@i42g2000cwa.googlegroups.com...

>
> Is it OK to aggressively thin latex paint with distilled water? My
> aim in doing so is NOT to increase coverage, but rather to improve the
> penetration into splits and cracks and rough areas. My intent would
> be to allow this first thinned coat to soak in and dry thoroughly, then
> apply two more coats of the same product, unthinned.
>
> If the answer is "no", could you please give some technical explanation
> why it is not a good idea.

The best technical explanation is simply that there are products made
specifically to do that, and they are going to do a better job than using
water.


jeffc

unread,
Aug 25, 2006, 11:53:49 PM8/25/06
to

"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1156431045.7...@p79g2000cwp.googlegroups.com...

>
> Norminn wrote:
>
>> Paint stores have product specifically for thinning both types of paint
>> and
>> which don't weaken the film.
>
> "doesn't weaken the film" is the part I want to understand better. Why
> doesn't this product "weaken the film" but water does? I'm not saying
> you're wrong, I just want to understand how it works.

Because it IS film. i.e. part of the binder. But it flows better. Anyway,
to fill cracks and other small imperfections, buy a paint specifically for
the job. Sherwin Williams sells PrepRite High Build Primer/Surfacer, or
even Block Filler (which is meant for concrete, I don't know how well it
would work on wood). Other companies probably have similar things.


jeffc

unread,
Aug 25, 2006, 11:49:04 PM8/25/06
to

"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1156425282....@p79g2000cwp.googlegroups.com...

>
> The cracks I am talking about are not large cracks that could be
> caulked. I'm talking about many fine splits in the wood; of the order
> of the thickness of a piece of paper. The unthinned paint simply
> cannot get in there thoroughly, no matter how aggressively I brush it.
> And, as it cures it leaves pinholes where the splits are; pinholes
> where water could get in.

What you're looking for is a "block filler" paint/primer.


Message has been deleted

Ether Jones

unread,
Aug 27, 2006, 5:57:06 PM8/27/06
to

jeffc wrote:
> "Ether Jones" <Ether...@yahoo.com> wrote in message
> news:1156431045.7...@p79g2000cwp.googlegroups.com...
> >
> > Norminn wrote:
> >
> >> Paint stores have product specifically for thinning both types of paint
> >> and
> >> which don't weaken the film.
> >
> > "doesn't weaken the film" is the part I want to understand better. Why
> > doesn't this product "weaken the film" but water does? I'm not saying
> > you're wrong, I just want to understand how it works.
>
> Because it IS film. i.e. part of the binder.

No disagreeing with you, but where did you get this information? There
is no information on the product label, and the MSDS lists no
ingredients at all.


> But it flows better. Anyway,
> to fill cracks and other small imperfections, buy a paint specifically for
> the job. Sherwin Williams sells PrepRite High Build Primer/Surfacer, or
> even Block Filler (which is meant for concrete, I don't know how well it
> would work on wood). Other companies probably have similar things.

I have looked and looked, and asked many contractors and paint store
gurus, and no one has been able to recommend such a product for the
application at hand. Remember, this application is for exterior,
horizontal, previously painted, weathered, wood, exposed to sun, rain,
snow, and heavy foot traffic. If anyone knows of a specific product
name and manufacturer for a product like jeffc has mentioned, please
post it.

Ether Jones

unread,
Aug 27, 2006, 6:05:26 PM8/27/06
to

Well no offense jeffc, but that's certainly not a technical explanation
and not very helpful.

BUT... if you find answers like that satisfying, more power to you.
Vive la difference.

Steve B

unread,
Aug 27, 2006, 6:35:10 PM8/27/06
to

"Ether Jones" <Ether...@yahoo.com> wrote

>
> No disagreeing with you, but where did you get this information? There
> is no information on the product label, and the MSDS lists no
> ingredients at all.

Just do what I did. I wrote to the company and asked them to please send me
the private patent information that contains all their ingredients and trade
secrets. They sent them to me immediately.

Steve


Steve B

unread,
Aug 27, 2006, 6:38:52 PM8/27/06
to

"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1156716326.4...@h48g2000cwc.googlegroups.com...

I guess I'm stupid. I totally understood what Jeff was saying. I do the
same things when traveling by airplane, going over a bridge, or turning on
the lights.

I really don't have to understand everything that makes them work, and I
sure couldn't explain it to a Piled High and Deep type of person in a
conversation, but then, I'm just one of those stupid nontechnical types.

Steve


Norminn

unread,
Aug 28, 2006, 8:13:11 AM8/28/06
to

This thread has a distinct odor of troll .. why don't you take your vast
scientific conversation to a paint chemist at a paint company? The
whole idea behind paint is to keep wood from getting split, cracked and
weathered, so we yokels on ahr share our experience to try to help
others. Paint products that I am familiar with say "don't thin more
than 10%", "sand weathered wood", "apply to clean, dry surface", "prime
bare wood", etc. Since painting is a good deal of work, the preparation
being the most tedious, we haul out the brushes and tarps and get the
job done before the item to be protected turns to crap. You have been
offered good faith advice, but challenge everyone who replies. By the
time you get around to doing the project, the house will be falling down.

yeeha

unread,
Aug 28, 2006, 8:29:27 AM8/28/06
to

Ether Jones wrote:

> BUT... if you find answers like that satisfying, more power to you.
> Vive la difference.

just paint the fucking board and stop fuckin around

you coulda been done by now
damn nickel holding up a dollar

you sure don't ask for much for nothing do you

you're a real pill

"it puts the brush into the paint and paints the board"

"PAINT THE FUCKING BOARD"

m Ransley

unread,
Aug 28, 2006, 8:33:52 AM8/28/06
to
You should be using Decking products, following instructions and not
making up your own with the wrong product. Your past failures might be
the wrong product, prep or aplication on a hot or damp surface. Get and
use products designed for the job and do what they say.

Norminn

unread,
Aug 28, 2006, 8:56:31 AM8/28/06
to
yeeha wrote:

I didn't want to be the first to use the "f" word, but, yeah. :o)

Steve B

unread,
Aug 28, 2006, 10:37:15 AM8/28/06
to

"m Ransley" <ran...@webtv.net> wrote in message
news:18547-44F...@storefull-3131.bay.webtv.net...

That may work for some here, but others insist that a person totally
understand and comprehend what the paint is doing, why, and all the
ingredients of said paint.

IOW, they do more thinking than painting.

Steve


Ether Jones

unread,
Aug 28, 2006, 12:21:20 PM8/28/06
to

Most decking products are stains, not paint. Unfortunately, I'm
constrained to use paint since the former owner painted the entire
porch and I want it to match. Only the breezeway area (about 150
square feet) and steps need refinishing.

Two years ago, I essentially followed the advice you recommended above.
The result was unsuccessful, despite scrupulously following the label
instructions. I think I posted the details elsewhere in this thread.
The paint started to fail after one year. I still don't know why for
sure, although many here have suggested possible reasons, and the oil
primer seems to be the likely culprit, even though "latex over oil
primer" is the conventional wisdom.

Some folks say "paint all six sides", others say "no, leave the
underside unpainted so the wood can breathe". I tried both ways and
they both failed (six sides on the steps, only the top in the breezeway
area).

Some folks say "use oil", others say "no, oil is too brittle and
moisture-impermeable and will crack and separate from the wood as the
wood expands and contracts due to moisture". I used latex over oil
primer, as recommended on the latex label. Perhaps the "oil is too
brittle" folks are right. That's my current working hypothesis at any
rate.

So this summer I tried a different approach.

One set of steps I pressure washed to blast off as much blistering
paint as possible. Let it dry and sanded it, then applied the latex
with no oil primer. The latex is a high quality 100% acrylic latex
paint rated for exterior horizontal surfaces exposed to foot traffic
and weather. On half the steps I applied the latex unthinned (as per
label directions), on the other half I used thinned latex for the first
coat (in order to penetrate better into hairline cracks and the spaces
between the boards) and then 2 coats of unthinned.

On the other set of steps I removed all the treads and risers, and
completely removed all previous coating with a planer, edger, and belt
sander. I used a different approach on each of the 12 boards,
including replacing some of the boards with new wood; but in all cases
I coated all six sides (that's why I removed the boards). For example,
on one of the boards I applied the latex directly to the wood without a
primer. On another I used thinned latex as the first coat, then 2
coats of unthinned latex over that. On another I stained the board
first with Cabot semi-solid deck stain, then applied latex over that
(yes, I know that conventional wisdom says don't do this). On another
I used an oil-based water-sealing product which claimed it was
paintable, then oil-primed and latex topcoat over that (letting each
dry thoroughly of course). I kept a record of how each board was
prepared. In a couple of years I'll see the results. Hopefully, at
least one approach will endure.

I haven't re-done the breezeway area yet, but the plan is to do it the
same way as the first set of steps mentioned above (power-wash to
remove blistering paint, then apply latex without oil primer).
Removing the breezeway boards to paint the undersides and edges and
ends is out of the question. Using oil in this area is extremely
inconvenient - after power washing, the waiting period for proper
drying would be a real problem. Oil requires absolutely bone-dry
wood. Any moisture stops the penetration. Latex is far more forgiving
in this regard.

The one question that remains unanswered, and the one that has offended
and/or angered some posters to this thread, is the issue of thinning
latex paint with water. I was hoping there might be an old-timer or
two here who understood this issue and could shed some light:

Many latex paint labels say "do not thin". The question I was
exploring is whether this "do not thin" exhortation is universally
true, or whether there might be extenuating circumstances wherein in
would be permissible, even beneficial, to thin just the first coat, to
improve penetration into nooks and crannies and spaces between boards,
as long as an unthinned second (or even third) coat of unthinned is
applied.

I tried to find a suitable water-based primer for this application but
was unsuccessful. I looked at MANY paint stores and home-improvement
centers, and spoke with a few contractors and painter friends. I have
yet to find a water-based primer that is rated for horizontal wood
surfaces exposed to rain and foot traffic. One guy swore by Zinser
123, so I bought a gallon, but when I got home and read all the fine
print, it categorically stated "not for use on horizontal surfaces
exposed to foot traffic and water".

I've also read that you should always use a primer and topcoat from the
same manufacturer to assure they are compatible. I'm not sure if this
is true, or if true, why.

If anyone knows of a water-based primer designed for use on
previously-painted weathered wood which has been power-washed to clean
it and remove loose paint, and which is compatible with
Sherwin-Williams 100% acrylic latex exterior porch and floor paint,
please post.

Ether Jones

unread,
Aug 29, 2006, 8:22:09 PM8/29/06
to

Ether Jones wrote:
> Is it OK to aggressively thin latex paint with distilled water? My
> aim in doing so is NOT to increase coverage, but rather to improve the
> penetration into splits and cracks and rough areas. My intent would
> be to allow this first thinned coat to soak in and dry thoroughly, then
> apply two more coats of the same product, unthinned.
>
> If the answer is "no", could you please give some technical explanation
> why it is not a good idea.

I think I've finally found a (partial) answer to my question; I'll post
it here for the benefit of anyone else who might be interested:

The major solvent in today's latex paints is water. But they also
contain small amounts of organic solvents, such as 2-(2 butoxyethoxy)
ethanol and trimethylpentanediol isobutyrate, which function as
"coalescing solvents". These coalescing solvents play an important
role in the film formation, and apparently the RATIO of organic solvent
to water affects the film formation. At least that's what the
technical discussion in the link below appears to be saying. SO... the
reason why adding too much water could be a bad idea is NOT that there
is "less binder" in the thinned latex, but rather that the thinned
latex has the wrong ratio of water-to-organic-solvent... and this
apparently affects the chemistry of the film formation process.

more details at this link:
http://www.dow.com/ucarlatex/coatingsconnection/archive/0311.htm

The proof is in the pudding, though, I suppose. Yesterday I blasted
the breezeway area of the porch with the power washer. Large sheets
and small flakes of old paint were flying everywhere. But the test
patches where I had applied thinned latex to scraped-bare wood 3 days
prior held fast and showed no sign at all of coming loose or wearing
off. So the plan is to use thinned latex for the first coat to
penetrate into hard-to-reach places (like between adjacent deck boards,
and where railing posts sit on the deck boards, and hairline splits in
the boards); and topcoat that twice with unthinned. I'll know by next
year if this approach is better than the latex-over-oil-primer approach
I used 2 years ago which failed in one year.

Thanks to all those who contributed.

soup...@_______.com

unread,
Aug 30, 2006, 11:16:19 AM8/30/06
to
Just add some mineral spirits. Whats so hard about that.
Gasoline works too.
Message has been deleted

Ether Jones

unread,
Aug 30, 2006, 9:49:33 PM8/30/06
to

NickySantoro wrote:

> For your situation the most effective procedure is to use a slow
> drying oil based primer thinned slightly, allowing it to dry
> thoroughly, then topcoating with the finish of choice.

Can you recommend a specific brand and model of primer, which is
explicitly rated for exterior wood floor and steps?

Ether Jones

unread,
Aug 30, 2006, 10:06:05 PM8/30/06
to
NickySantoro wrote:
> On 29 Aug 2006 17:22:09 -0700, "Ether Jones" <Ether...@yahoo.com>

> wrote:
> I'll know by next
> >year if this approach is better than the latex-over-oil-primer approach
> >I used 2 years ago which failed in one year.
> >
>
> If it failed it was due to causes as yet unrevealed, likely improper
> application or inadequate surface preparation.

Perhaps, but the application and prep were meticulous. All treads and
risers were removed and thoroughly scraped, wire-brushed, sanded, and
brushed. Primed with oil primer all six sides. Top-coated with 2
coats of porch and floor latex all six sides.

So the other possibility is perhaps the conventional wisdom of latex
topcoat over oil primer is not universally correct for all
applications. FWIW, I spent 30 minutes in a paint store this afternoon
reading the label of each and every different exterior primer, both oil
and latex (8 or so different cans). Not a single one of them listed
exterior wood floors or steps as an acceptable application. Some of
the highly-touted brands such as Zinser 123 and Kilz explicitly
excluded exterior wood floors and steps.

It will take a couple of years, but my experiment with the backyard
porch steps should be most interesting:

http://groups.google.com/group/alt.home.repair/msg/1f2d2dd773730bb1?dmode=source&hl=en&output=gplain

Larry Jaques

unread,
Sep 4, 2006, 1:24:20 AM9/4/06
to
On 23 Aug 2006 17:04:16 -0700, with neither quill nor qualm, "Ether
Jones" <Ether...@yahoo.com> quickly quoth:

>
>Is it OK to aggressively thin latex paint with distilled water? My
>aim in doing so is NOT to increase coverage, but rather to improve the
>penetration into splits and cracks and rough areas. My intent would
>be to allow this first thinned coat to soak in and dry thoroughly, then
>apply two more coats of the same product, unthinned.

By overthinning the latex paint, you break down the chemical bonding
of the "glue" base which holds it together. Any paint over the top
would be more easily removed.


>If the answer is "no", could you please give some technical explanation
>why it is not a good idea.

Jus' cuz.


>I already tried this on some old treated pine deck boards I used to
>repair portions of an exterior porch stairs. I washed and rinsed the
>boards, then let them dry thoroughly. Then I painted them with an
>exterior acrylic latex porch paint thinned 50/50 with distilled water.
> This first coat had remarkable penetration. After it dried
>thoroughly (a couple of days in 85 degree weather in the garage) I put
>2 more coats of the same product, unthinned, allowing thorough drying
>between coats. I used these boards to replace some worn exterior
>porch stair treads, but they've only been in place for a couple of
>weeks so far so I won't know the results for a couple of years.
>
>In the past, I've used an oil primer, followed by 2 coats of latex
>topcoat, but haven't had very good results. The latex bonded
>tenaciously to the primer, but the primer blistered and peeled away

Blistering and peeling are indicators of moisture damage. Since the
primer came up, too, I'd wager that it was the wood which was still
wet.


>from the wood. This exterior application sees lots of sun, rain,
>snow, and foot traffic.

Make POSITIVE SURE that the wood is dry, the primer is dry [I'd use
all oil-based if it was available, all latex (including primer) if
not.] As you have seen, 2 days at 85F wasn't enough to dry the wood
after washing. Also, make sure it's properly rinsed. Soap films can be
really tenacious. Give it a week to dry AND protect it from dew.

Another possibility arises when you paint things out in the sun. It's
best to paint while it's warm and dry, but not in the direct sunlight
if at all possible. That, too, can cause blistering as the outside
layer of paint dries more quickly than the inside, sealing in more
moisture than it normally would. (I've only read about this part, not
experienced it firsthand.)

Also avoid cheap paints. Good, durable, long-lived paint ain't cheap.

G'luck!


--
The clear and present danger of top-posting explored at:
http://www.netmeister.org/news/learn2quote2.html
------------------------------------------------------
http://diversify.com Premium Website Development

Larry Jaques

unread,
Sep 4, 2006, 1:35:48 AM9/4/06
to
On 24 Aug 2006 14:04:23 -0700, with neither quill nor qualm, "Ether
Jones" <Ether...@yahoo.com> quickly quoth:

>


>Steve B wrote:
>
>> Look at the two.
>
>I just looked at a container of Floetrol today. Until now, I'd never
>heard of it.

Floetrol is a latex medium with additional binders which are not in
water. It's good stuff. (I have a quart of it on my kitchen floor
waiting to be used with the latex enamel I'll use to repaint all the
interior house trim this month.)


>> The product is every bit as thick as latex paint.
>
>Very cheap latex paint maybe. Floetrol is nowhere near as thick as the
>latex paints I have been using.
>
>> It has the same polymers and surfactants as latex paint. It has added polymers and surfactants to help the paint flow and "skin" properly.
>
>How do you know this? The label on the container lists no ingredients.
> The MSDS doesn't list any ingredients (it does say the boiling point
>is 212F though). Where did you get your information?

Perhaps here:
http://www.flood.com/Flood/CustomerSupport/FAQ/DIY/Floetrol+FAQ.htm


>If I paint one board with 8 ounces of high quality latex paint, using
>as many coats as it takes to use up the paint, and I paint a second
>board with 8 ounces of the same high quality latex paint plus 2 ounces
>of distilled water, again using as many coats as it takes to use up the
>10 ounces of thinned paint, are you saying the second board has a
>"weaker" film? And if so, _why_?

Yes. Take an ounce of Elmer's glue. Thin it with water. Does it still
work as well? You've thinned out the chemical bonding. Ditto your
thinned paint. Most manufacturers ask you not to thin more than 10%
because it messes with the durability of their paint formula. You're
thinning 25-50% and it'll come back to bite you, ah gare-on-tee.

If you're low on engine oil in your car, it is recommended that you
don't add water to that, either. ;)


>OT, just heard on the news - Pluto has been stripped of its planet
>status.

This just in: Everything We (You) Know Is Wrong. The sun isn't going
down, the horizon is moving UP!

m Ransley

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Sep 4, 2006, 8:06:02 AM9/4/06
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You wont know with your experiment till it fails, what if it peals in
sheets in 4 years, well it could. Quit experimenting and follow
directions. Primer for decks is often paint thinned properly, properly
is the key.

Ether Jones

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Sep 4, 2006, 8:56:15 AM9/4/06
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m Ransley wrote:

> Quit experimenting and follow directions.

That was the whole point of the message to which you were responding:
WHAT directions?

Can you recommend (by brand name and model number) even ONE primer
whose labelling explicitly allows usage on horizontal wood surfaces
exposed to weather and foot traffic?

Ether Jones

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Sep 4, 2006, 9:27:12 AM9/4/06
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Larry Jaques wrote:
> On 24 Aug 2006 14:04:23 -0700, with neither quill nor qualm, "Ether
> Jones" <Ether...@yahoo.com> quickly quoth:
>
> >
> >Steve B wrote:
> >> It has the same polymers and surfactants as latex paint. It has added polymers and surfactants to help the paint flow and "skin" properly.
> >
> >How do you know this? The label on the container lists no ingredients.
> > The MSDS doesn't list any ingredients (it does say the boiling point
> >is 212F though). Where did you get your information?
>
> Perhaps here:
> http://www.flood.com/Flood/CustomerSupport/FAQ/DIY/Floetrol+FAQ.htm

Or not. I've read that link. There is no mention at all of polymers
or surfactants. All its says is that Floetrol contains "conditioners".
My shampoo contains "conditioners" too... maybe I could use that?
It's cheaper... :-)


> If you're low on engine oil in your car, it is recommended that you
> don't add water to that, either. ;)

It's also recommended in my car owner's manual that I do NOT add
third-party additives to my oil, either. Just like the label on my
latex which says "Do not thin"... not "Do not thin, except with
Floetrol, which, although made by our competitor, contains the exact
same chemistry as our proprietary acrylic binding system".


I'll probably pick up a gallon of Floetrol today and give it a try on
some of the boards I am refinishing and give it a fair try. It would
be nice to have more information about it though. Like what's in it.

Steve B

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Sep 4, 2006, 12:30:55 PM9/4/06
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"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1157376432....@h48g2000cwc.googlegroups.com...

Just paint the fucking boards and shut up, already!

Sheesh!

Steve


Ether Jones

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Sep 4, 2006, 4:26:25 PM9/4/06
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The sarcasm is misplaced.

If you don't know what's in the product, don't be telling people you
do.

By the way, patents are not "private". If it was patented (which it is
not), that information would be publicly available.

Steve B

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Sep 5, 2006, 12:57:18 AM9/5/06
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"Ether Jones" <Ether...@yahoo.com> wrote in message
news:1157401585.8...@b28g2000cwb.googlegroups.com...

Good God, Man. Do you beat dead horses for a living, or just for fun?

Steve


m Ransley

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Sep 5, 2006, 8:04:36 AM9/5/06
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Do what the deck paint label says, or call the manufacturer. For oil
deck paint the usual recomended way by manufacturers that is printed on
labels is thin the oil paint with thinner. Ive only thinned latex to
make it original in thickness after it has thickened by air, Ive never
thinned to spray. The usual max recomended thinning of latex is 10% for
spraying. Each product is different, follow its instructions. Your
previous failures may be to damp a wood [ use a moisture meter ] I do.
Or to hot in sun, to humid, to cold etc etc. Or even crappy paint.

Ether Jones

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Sep 5, 2006, 10:03:57 AM9/5/06
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Just got off the phone with the tech support person for the latex I am
using this year. What she said surprised me but also fit the facts of
my personal experience. She said DON'T USE PRIMER. When I asked
why, she said there ARE NO PRIMERS that hold up well to foot traffic.
Well, that certainly is in agreement with my previous experience, and
would explain why the paint on my porch steps failed so quickly.

Two years ago I oil-primed and latex-topcoated the porch steps, and the
system failed after one year. The paint was adhering to the primer,
but the primer was peeling from the wood. The latex I used back then
was Dutch Boy Porch and Floor, and the label directions said to use an
oil primer, so I did. In an earlier post, I speculated that the reason
for the failure might be that the "conventional wisdom" (latex topcoat
over oil primer) did not apply to what I was trying to do (horizontal
wood exposed to weather and foot traffic). Looks like that might be
correct.

The porch and floor latex I am using this year (made by Sherwin
Williams) does NOT say to use an oil primer, or any primer for that
matter.

The tech rep also said that even though the label says "do not thin",
it is OK to thin with water up to 12% FOR THE FIRST COAT ONLY to
improve penetration into hard-to-reach places as long as there is a
second, unthinned coat applied.

At any rate, the next couple of years should be interesting to see what
happens. One set of steps I power-washed, let dry, and painted with
no primer, just like the label said. On a few of the steps I thinned
with water for the first coat. The other set of steps I disassembled,
planed, power-sanded, and applied paint/primer/stain/sealer in many
different combinations to see which would hold up better.

jonpa...@gmail.com

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Dec 12, 2014, 12:49:50 PM12/12/14
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Mr. Jones, I commend you on your patience & methodology. Both on how you handled this thread, as well as your experiments with your steps.

I am disappointed however, that you have never posted the results/findings of your investigation. Although I can hardly blame you based on replies & feedback you were getting from other posters. But I would appreciate very much for you to kindly share what you have learned.

You express yourself clearly & concisely, your questions are valid & pertinent and your logic has been sound. You have a genuine thirst for knowledge & a hunger for the truth. You are not ego-driven like nearly all of those who commented on your question (I can't say "answered" because none did, and even saying "responded" seems to imply more relevance & substance than most posts contained)- you were merely seeking information, which in the end you were able to obtain on your own.
It is rather disturbing how poor the average/typical levels are for such basic skills as reading, comprehension & short-term memory, which this thread exemplifies. It's baffling to me why everyone seemed to get so worked up, trying to turn it around & criticize the question or you- even resorting to swearing & name calling all because THEY were unable to answer your question or even provide any truly useful, pertinent information. People can be so ridiculous, silly & ignorant.

In any case, thank you! I found the information you shared very helpful and informative.

philo

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Dec 12, 2014, 1:11:43 PM12/12/14
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On 12/12/2014 11:49 AM, jonpa...@gmail.com wrote:
> On Tuesday, September 5, 2006 10:03:57 AM UTC-4, Ether Jones wrote:
>



!!!LOOK AT THE DATE!!!!

capn...@gmail.com

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Mar 1, 2016, 5:00:39 AM3/1/16
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I agree with Jonpa..., most of the information was useful and informative. The posters replying to the thread didn't seem to grasp the idea of what was being discussed, and offered little in that direction.

Mineral spirits? Gasoline? Just follow the directions? The reason for using primer in the first place is to fill in the bumps, creases, and other imperfections on the bare wood. The same is true of the primer you spray on your car's body to avoid rust.

My problem isn't decking, mine is beehive lids that absorb huge amounts of moisture from the respiration of the bees clustering in winter. The wet wood lifts the paint and flakes it off. Acrylic primer doesn't seem to work at all.

As for the date, we're aware of it, Philo. We're wishing for a followup to the experiment concerning the thinned paint as a primer substitute.

Terry Coombs

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Mar 1, 2016, 7:40:56 AM3/1/16
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capn...@gmail.com wrote:
>
> My problem isn't decking, mine is beehive lids that absorb huge
> amounts of moisture from the respiration of the bees clustering in
> winter. The wet wood lifts the paint and flakes it off. Acrylic
> primer doesn't seem to work at all.
>

Quilt boxes . That is , a shallow tray above the cluster that's filled
with wood shavings or other absorbent material . Do you have an upper
opening for warm moist air to escape ? If not , I'm surprised you don't have
cold water dripping on the bees , a sure way to kill a colony .
I use an inner cover with an outer that's covered by aluminum flashing ,
no paint on my covers .
--
Snag


cl...@snyder.on.ca

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Mar 1, 2016, 12:16:43 PM3/1/16
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The funstion you are referring to is the filler. A "primer" enhances
adhesion of the paint to the substrate. Thinned latex isn't much good
for either.
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