I am in the process of laying down multiple thin wipe on coats of poly
to a project.
The first half dozen coats were done in gloss. Then I switched to
semi-gloss for the final two coats. The first coat of semi-gloss,
still left the wood with a pretty high sheen.
Will the semi-gloss (i.e. less sheen than gloss) nature continue to
build with additional coats of semi-gloss additional or will I need to
go to satin if I want the surface to be less shiny?
i.e. is the non-gloss sheen just determined by the top coat or does it
build across multiple coats?
You did stir well? The matting compound sinks to the bottom and the
top layer is therefore high gloss.
I'm not saying that is what happened but not uncommon.
r
Probably more common than it should be.
If that is not the case, and you DID mix well, consider this:
The flattening materials in your finish are finely ground particulates
held suspended in solution by the viscosity of the material. (When
well stirred!)
But look at your material and its application. The reason you have to
put 10 coats of finish on your piece is because the thickness of the
material left behind is quite thin. You apply the material, and wipe
a great deal of it off. This means you are wiping off the flattening
agents as well as the resin finish.
So when you apply a top coat of a product with a different reflective
factor, you will probably have to apply several coats to acheive "semi
gloss" as you final gloss. And since you are going over a previously
finished area, you are probably not putting on as much finish as you
think. If you are putting the new finish down on a smooth, previously
finished project and then wiping smooth, you may have less than a mil
of finish actually on the surface.
That will probably dry to less than 1/2, probably more like 1/3 of a
mil of finish. Check out the manufacturer's recommended final finish
thickness; I would almost bet without seeing the stuff it will be 3
mil.
Of course, all of the above depends on your "hand" and application
technique, but if I were you I would keep putting on the finish to get
to the desired gloss/reflectivity.
Personally, I know there is a large camp of folks that like to use the
gloss, then knock it back with 4X steel wool or a scoth brite pad,
but getting every single crack, crevice, corner, and detail finished
to exactly the same reflectivity perfectly across the whole project
can take a huge amount of time.
Just keep on going, you'll get there.
Next time, you might want to start with a piece of scrap from your
project and try the semi gloss on all coats compared to your present
method of half semi and half full gloss. Depending on the actual
finish, there probably won't be that much difference in the final
appearance.
Robert
If you are happy with the finish but not the gloss, try knocking it
down with a fiber matted scouring pad (kitchenware or cleaning aisle).
On large surfaces, use one under an orbital sander. A coat of wax
keeps it looking good.
P
Yes, the sheen is determined by the top coat (assuming it is applied heavily
enough to actually make a decent film thickness); i.e., varnish does not
melt into preceding coats as do lacquer and shellac. Since the semi-gloss
has a matting agent in it it must be thoroughly stirred before application
else you are putting on more glossy.
"Most" varnishes do not meld in to the previous coats. Gel varnishes do in
fact meld into preceding coats. With gel varnishes you do not have to scuff
the precious coat before applying the next and you can repair a previous
coat that may have a glob that you missed while wiping by simply applying
more of the gel varnish to that area. That glob will soften and smooth out.
A few other oddities about gel varnishes, there is no stirring to mix in the
matting agent, it stays permanently suspended. Additionally I have yet to
see a gel varnish that comes in a "gloss". Because gel varnishes go on thin
and yield a finish that gives spraying a run for its money in smoothness, it
seems like a gloss finish would be a naturally "easy to apply finish" with a
gel. I'll have to e-mail Lawrence McFadden and find out the skinny on that.
;~)
Check the link below. At the bottom of the referenced page (if the
link works), you will see another link to a pdf labeled "Bartley Gel
Finishes brochure". When you click on the link and open the pdf, you
will see an old standard, Bartley wipe on varnish < in satin >. While
I have used their satin, I have actually never used their gloss.
As a sidebar, while it may be different now, in the ancient old days
of gel finishes, they did want you to gently stir (not mix) the
product before use to make sure the product was "consistent in
application". Maybe long truck rides in hot trucks that distributed
to warehouses were a consideration at one time.
Dunno.
But, the OP was asking about poly. Is your new favorite a poly or a
varnish? Don't confuse me, as I was telling someone this last weekend
(that can't afford for me to finish his piece of furniture) that you
had come across a finish that you liked a lot, and had great luck in
application.
If it is a varnish, he will probably try it. If it is a poly, he
won't. It looks like LMF makes the wipe on poly, and Bartley's makes
the wipe on varnish.
Going to the LMF site does no good. When their home page opens it
ONLY describes a polyurethane finish as their wipe on gel.
BUT... when you go to the bottom of that page and load their pdf on
Bartley gel, the can they show in the brochure is clearly marked as
varnish.
So is the LMF poly the product you are using or are you using the
Bartley's varnish?
Details, please.
If LMF doesn't have a gloss wipe on, don't worry. You can get gloss
wipe on from Minwax (hey don't laugh - it's pretty good!), Cabot,
Valspar, Old Masters, Zar, and a few others.
I have used the Old Masters (excellent) and the Minwax (almost as
good) personally, but not the others in gloss wipe on.
Let me know which finish you are using that you like so much, por
favor.
Robert
I never saw the link but did see the pdf Bartley brochure. I didn't see the
gloss there either. The web site was moving dead slow and I did not look
further.
Yeah actually thinking back, I witness a liquid that will form on the top if
it sets for several weeks/months, I'll stir that in. But for daily use
stirring was/is not necessary.
Yeah I was mostly commenting that you could meld with the gel products.
Is your new favorite a poly or a
LOL, let me start off with my definition of a varnish.
A paint containing a solvent and an oxidizing or evaporating binder, used to
coat a surface with a hard, glossy, transparent film.
The smooth coating or gloss resulting from the application of this paint.
I consider any clear finish that adds a top protective layer, a varnish.
Personally I started using Bartley gel "Varnishes" in 1989 and only last
year switched over to the LMF after learning that LMF had acquired the
Bartley line of finishes. I cannot tell any difference between the
resulting clear finish of the Bartley's or the LMF. That said, I switched
only because of the free offer from LMF and stayed with the LMF over the
Bartley varnish because of a more consistent application. Often I got
Bartley varnishes that were inconsistent in viscosity in the can.
That is what it looks like however again I cannot tell the difference and
again I consider polyurethane a varnish as per the definition above.
Neither have the plasticy look after 3 or 4 coats.
I see the same but did not see the Bartley's gloss varnish
Currently using LMF, "was" using Bartley's for about 19 years. Now that LMF
manufactures the Bartley's products there may be a more consistent quality
in their product.
I don't see a difference in the two except that the Bartely's seems to add a
bit of a golden tone to the wood, LMF seems to leve the color more natural.
I'm basically lazy in this respect, I want only to use one product. I
prefer satin to any other finish, however some of my customers prefer gloss.
When I need a gloss finish I use General Finishes Arm-r-Seal gloss. I wipe
on the first sealer coat, wipe off the excess and let dry. I follow that
with a scuff sanding, and a single coat applied with a quality/Wooster
"foam"brush. It goes on heavy with that final coat and you have to apply it
and not work it. Again that finish looks sprayed.
Again I use the above mentioned General finishes for a gloss finish but find
that the glossy finish shows wipe marks if the final coat is not applied
with a foam brush. The foam brush holds tons of varnish.
'> favor.
In the last 8-9 months it is the LMF Gel Poly , and again I cannot see a
viable difference between it and the Bartley' except for the warmer golden
tone of the Bartley's. Both require thinner/oil based product for clean up.
Oh, one thing I do notice, the LMF gel has a purple'ish tint in the can,
the Bartley's looks more like Vaseline.
Leon
Also read Tom Watson's comment. He has the same thoughts on a "Varnish".
He also mentions that Bartely's and LMF both contain Poly.
Something to think about and or investigate further.
Some varnishes have polyurethane resins. Some do not. It is my
understanding that most resins used in varnish are cheap polyester
resins. They are soft, flexible, and do the trick for most of us.
Polyurethane resins are added to make the finish coat harder than
without, and more abrasion resistant.
But almost all (wanna be careful here...) polyurethane finishes have
the same basic characteristics and formulas of varnishes, but with
polyurethane resins, less the polyesters. In the end, the poly <only>
products should be harder due to their resins.
My concern for the difference in the two would be the color they
impart. Any varnish product I have seen imparts an amber hue, and as
they age it seems to really come on strong. Some of the polys go on
almost clear with little ambering, but don't always warm up some types
of wood.
As far as LMF and Bartley's go, I would suspicion from further reading
that formulas may actually be significantly different between their
respective varnish and poly products. Your experience would seem to
bear this out when you describe the purplish tint of the LMF (we used
to call that "chroming") vs. the plain look of the Bartley's when both
are in their respective cans.
But... who knows for sure. Probably only LMF.
So many manufacturers now are simply revamping their old formulas it
is hard to know if you are getting the newest technology in coatings
or just an old lady in a new dress.
Robert
Well, the "evaporating" qualifies shellac as a varnish. That's pushing a
bit. And a "paint" usually contains pigment and is not a "transparent"
film.
But that's just me feeling pedantic this morning :-).
In reference to the subject of this thread, yes, multiple coats of a
finish with a flattening agent will decrease the gloss with each
additional coat. Assuming of course that it's been stirred :-). The
problem is that multiple coats also make the wood appear cloudy. I tell
customers if thy must use such finishes, use gloss for all but the last
coat, which they can do by NOT stirring. Or just use gloss and rub it out.
Blueman:
In reading through some of the responses to your inquiry it becomes
clear that some of the responders are not.
The silica flatting agent is in suspension, not in solution. There is
no such thing as being suspended in a solution.
Do a bit of reading on how the gloss is knocked down by the silica
breaking up the light and how finish hardness and the use of flatting
agents are related. This will help you make a decision about what to
use for a top coat.
The fact that something contains polyurethane does not preclude it
from being a varnish. These are definitional issues but not being
mindful of them can lead to confusion.
The Lawrence - McFaddden and the Bartley gel finishes both contain
polyurethane.
Jeff Jewitt's Homestead Finishes site is a good place to start looking
for answers.
Regards,
Tom
Thos.J.Watson - Cabinetmaker
tjwatson1ATcomcastDOTnet
www.home.comcast.net/~tjwatson1
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