Air bubbles - water based polyurathane
Phil Goode
Using Minwax water-based polyurathane on a pine desktop, I am getting lots
of small air bubbles. I stripped the top, sanded with 220 grit sandpaper,
applied stain, wiped the top with a damp rag to raise the grain, sanded
again with 220 grit. After that, I applied a thin coat of poly with a
bristle brush. After 4 hours, I sanded lightly with 440 grit and applied
second thin coat. After another 4 hours, I sanded with 440 and applied the
final coat. That coat developed quite a few tiny air bubbles. I was careful
to apply the poly slowly and with long strokes going with the grain.
Is this typical of water-based poly. I've used regular poly before and
haven't had this problem. I used water-based this time because of lack of
smell and ease of cleanup.
Any help?
Phil Goode
Mike Thompson
In <01bc251a$2918cd80$bbb25ccf@#philgo>, "Phil Goode" <phi...@ix.netcom.com> writes:
<Details of bubbles-in-the-finish woes snipped>
>Is this typical of water-based poly. I've used regular poly before and
>haven't had this problem. I used water-based this time because of lack of
>smell and ease of cleanup.
>
>Any help?
>
>Phil Goode
Phil, check Dejanews for past discussions of this topic - many different
techniques used to combat this typical-of-water-based-poly problem.
I can offer only this: I do mostly large stuff, entertainment centers,
dressers and the like. When I started using this finish and running into
the problem, I opted to go with a spray rig (Wagner Fine Coat) and that has
cured my problems. People who do smaller jobs have found different things
work for them.
There was in December 1995 a review of water-based polys on the market and
the bubble propensity was as a matter of fact a judging point (in addition
to hardness, ease of application, color fidelity and more). It was I think
in American Woodworker. I have the article in fax form saved on my home
machine and can forward the fax to you if you are interested.
The bottom line was that the tendency of a finish to bubble on application
varied quite a bit from brand to brand, and the best performers, I learned,
are sold to contractors in 5 gallon cans, at $30.00 a gallon. Not quite
targeted at the home woodworker :( wouldn't you say?
So try Dejanews for techniques, maybe try a different brand, or if you are
going to do a lot of finishing, go with a HVLP spray rig.
My 2 cents, anyway...
- Mike
********************* No IBM Opinions Here! ********************
Michael E. Thompson (Mich...@ausvmr.vnet.ibm.com)
T/L 678-0779 (512) 838-0779
IBM Austin, Austin, TX, USA
********************* No IBM Opinions Here! ********************
Phil Miller
In article <01bc251a$2918cd80$bbb25ccf@#philgo>, "Phil Goode"
<phi...@ix.netcom.com> wrote:
> Using Minwax water-based polyurathane on a pine desktop, I am getting lots
> of small air bubbles.
.
.
.
> Is this typical of water-based poly. I've used regular poly before and
> haven't had this problem. I used water-based this time because of lack of
> smell and ease of cleanup.
>
> Any help?
>
> Phil Goode
Phil,
I've had exactly the opposite problem. I got soooo many bubbles using
the recommend bristle brush with an ordinary PU that I finally had to
resort to a foam brush (which worked MUCH better).
On the other hand, I've used Minwax water-based PU with a bristle
brush without much bubbling. I bought the brush recommended on the can
(the brush was also made by Minwax and had a light blue handle). I think
it's important to get the correct brush -- it's my understanding that
bristle composition and whether the tips are flagged or not determines
whether it will work for a particular finish or not.
I'm assuming that you're not shaking or stirring the PU too vigorously
before applying...
FWIW, I applied the water-based PU over oak veneer that was sanded
with 240 grit.
I really liked the ease of use and clean up with the water-based PU and
would definately use it again.
Phil Miller
pmi...@mmm.com
Opinions expressed herein are my own and may not represent those of my employer.
R. Martin Caskey
I have two pieces of pine furniture, a dry sink and a trestle table, which
I plan to put on the covered portion of my deck. Although under cover,
they will still be subjected to rain blowing in. Both were unfinished
pieces purchased fifteen or more years ago, so both are actually well
made. Both were "antiqued" and varnished. I think the dry sink has satin
polyurathane, and I know the table has satin polyurathane on the legs and
gloss polyurathane on the top. I plan to sand both pieces to break through
the old polyurathane, but I am going to leave the antiquing in place.
What is the best finish to put on these pieces to keep them from becoming
hopelessly warped??
Thanks in advance.
Martin Caskey
Towson, Maryland
praxis.net
pmi...@mmm.com (Phil Miller) writes: > In article <01bc251a$2918cd80$bbb25ccf@#philgo>, "Phil Goode"
I do alot of finishing of new furniture and have decided that the pu's
are extremely difficult to get a perfect finish with. Due to drying times,
dust nibs, dive bombing bugs, but most of all air bubbles, have caused me
to go to a HVLP sprayer and lacquer. I believe your bubbles are being
produced by rubbing the brush on the can lip.I would try tapping instead of
wiping the bristles to remove the excess pu. Might work some
Good Luck
Dave Plumpe
In article <01bc251a$2918cd80$bbb25ccf@#philgo>, "Phil Goode" <phi...@ix.netcom.com> wrote:
>Using Minwax water-based polyurathane on a pine desktop, I am getting lots
Phil-
Minwax's "Polycrylic" has become my "finish of choice" - presently
doing red oak kitchen cabinets, as I build them one-at-a-time. I use 220 grit
between coats, apply 3 coats full-strength with a foam brush. I only thin if
it has thickened from being open too long. Don't play with the brush - wipe
it on with a little pressure, then a couple of light passes to even it out.
Have never used it over stain 'tho.
Bubbles form almost immediately, but dissipate before the finish
dries. Possibly your thinned coats dried before the bubbles had a chance to
burst. Or maybe it's the 6.5" of rain we had here in Feb :-(
2-3 yrs ago I did a small bedroom floor with Flecto's Diamond
Varathane, and won't use it again. Very bad bubbling with the recommended
application pad (but much harder surface than Polycrylic - needed for floors).
Also have tried Behr's water-based poly; it didn't level very well and gave
me some bubbles.
I've heard that adding milk (with its lactic acid) will cut down
bubbling, but I've never tried it. After 6-7 gallons of Polycrylic over the
past couple of years, I've never had a problem.
-Dave
plu...@innova.net Dave & Ellen Plumpe, on Lake Keowee in upstate SC.
Philip Tuley
@praxis.net wrote:
: pmi...@mmm.com (Phil Miller) writes: > In article <01bc251a$2918cd80$bbb25ccf@#philgo>, "Phil Goode"
: > <phi...@ix.netcom.com> wrote:
SNIP
: Phil,
: I do alot of finishing of new furniture and have decided that the pu's
: are extremely difficult to get a perfect finish with. Due to drying times,
: dust nibs, dive bombing bugs, but most of all air bubbles, have caused me
: to go to a HVLP sprayer and lacquer. I believe your bubbles are being
: produced by rubbing the brush on the can lip.I would try tapping instead of
: wiping the bristles to remove the excess pu. Might work some
: Good Luck
From yet another Philip (myself), I'd like to add to this last post my
suggestion, which is that you go to a second-hand store and look for a
stoneware or crockery pot that has no lip at all. Then when removing
excess PU, simply press against the side and there will not be the
problems you might encounter with a can.
--
-------------------------------------------------------------------------------
David Wagner
Phil Goode <phi...@ix.netcom.com> wrote in article
<01bc251a$2918cd80$bbb25ccf@#philgo>...
> Using Minwax water-based polyurathane on a pine desktop, I am getting
lots
> of small air bubbles...........>
> Is this typical of water-based poly. I've used regular poly before and
> haven't had this problem. I used water-based this time because of lack of
> smell and ease of cleanup.
> > Any help?
>
> Phil Goode
>
My experience is very similar to yours. While I've seen some suggestions
on how to reduce the problem, it seems that a product this difficult to
apply has very little utility for most of us. I don't want to spend more
time on finishing a project than I spend on building it. Consequently, I
quickly returned to the old standard Minwax hydrocarbon based
polyurethane. Maybe if no one buys the water-based product, Minwax will
get the message.
David Wagner
Dan Hamill
> Maybe if no one buys the water-based product, Minwax will
> get the message.
>
> David Wagner
>
That's an interesting point, but I think that the push toward water based
products is because of envirnomental concerns. So, hopefully if we don't
buy the brands we don't like the way they work, they will improve them.
I've tried to use water based as much as I can almost since it became
available, and have had all the typical problems, and really found no great
solutions. Just lately, however, I have had better luck. I recently found
that Minwax has a new brush out for these products, and it works very well.
I have always made it a point to but Simms brand brushes, as they are made
in New Brunswick, Canada (where I'm from) but bought this to try, and liked
it. I hope Simms comes out with a similar one.
Take care all,
Dan Hamill
Andrew Patterson
Phil Goode <phi...@ix.netcom.com> wrote in article
<01bc251a$2918cd80$bbb25ccf@#philgo>...
> Using Minwax water-based polyurathane on a pine desktop, I am getting
lots
> of small air bubbles.
[et cetera]
Just in case this was overlooked, and as nobody else mentioned this, you
did gently stir it rather than shake it, correct?
Andrew
Phil Goode
Yes, I stirred gently. Unlike 007 "shaken not stirred".
Phil
Andrew Patterson <a...@nosc.mil> wrote in article
<01bc27fc$fa0e6320$94883180@ifozdex>...
beachc...@gmail.com
cl...@snyder.on.ca
wrote:
>I know this is a old thread but I'm sure it's still an ongoing problem. So I spent hours googling and reading on how to apply without brushstrokes and bubbles. Well I tried everything. I spend hours applying sanding applying again and so on. Bubbles and brushstroks were ongoing. Finally I tried a kitchen sponge. Got it wet first, wringed it out and dipped it in the poly and applied it that way. NO bubbles or brush lines finally. DONT use the sponge on a stick. Bubbles are worse. Just a cheap dish sponge.
either with water or poly. Get all the air out of the foam, then lay
the poly on smoothl;y
martinb...@gmail.com
> Using Minwax water-based polyurathane on a pine desktop, I am getting lots
> again with 220 grit. After that, I applied a thin coat of poly with a
> bristle brush. After 4 hours, I sanded lightly with 440 grit and applied
> second thin coat. After another 4 hours, I sanded with 440 and applied the
> final coat. That coat developed quite a few tiny air bubbles. I was careful
> to apply the poly slowly and with long strokes going with the grain.
>
martinb...@gmail.com
Larry Kraus
that it cannot dry quickly. In twenty years the air will work it's way
out and you can let the surface dry.
Leon
I was wondering too, did he stir or shake the can to mix?