Lacquer Clear Coat - Ups and Downs for Pinball
c...@provide.net
someone asked why no one talks about clear coating Playfields with
clear lacquer. I have lots and lots of experience with lacquer,
so i'll lay out the good and the bad of this product.
This is all my opinion, so take it for what it is worth.
Most (if not all) pre-Diamondplate playfields are lacquer based.
So basically anything from the 1950s to pre-1990 is lacquer.
There are some exceptions, like a few late 1980s Whirlwinds to
Funhouses coated with diamondplate, but essentially anything
before Terminator2 is usually lacquer in WMS games. I forget the
first Stealthcoat DataEast game, but it's about the same time frame
(1992). To my knowledge, Gottlieb *always* used lacquer and never
used Urethanes. And again to my knowledge, all Capcom games used
Urethanes.
Speaking of urethane... that's the product used on the 1990s
"diamondplate" and "stealcoat" playfields. It is a very high
solid auto finish. High solids means it has a lower VOC
(volatile organic compound) level, so it pollutes less to
spray it. Basically it is illegal to spray lacquer now (low
solids compared to urethane) in a production environment (there
are exceptions though, like the furniture industry). Urethane
is extremely durable, hard, yet flexible (to some degree).
It is also a 2-part finish, using a hardner. After urethane
is spray, there is a 24 hour "window" before the finish becomes
so hard, that it essentially can not be over sprayed without
sanding it first (sanding increases the surface area for the
new paint to better adhere). Because of it's hardness, it's an
ideal finish for a pinball playfield!
Anyway, this isn't about urethane, it's about lacquer! Lacquer
comes in two flavors: nitrocellulose and acrylic. But first some
general info about paint...
Paint is made of three major components: pigment, binder (also known
as resin), and solvent. Pigment is the what makes the color.
Pigments can be organic or inorganic. Organic pigments, though
more expensive, offer a wider range of shades. Inorganic pigments
are derived from various metallic ores. For example, white is made
from titanium dioxide, black is carbon, zinc is yellow, orange is
molybdate, and red is made from iron oxides.
Pigments are dispersed in binders, often called resins, which
provide the protective and mechanical properties of the paint
film. As paint dries, the binder forms a film that allows the
paint to adhere to the surface. Early binders were made from
natural materials such as linseed and soybean oil. These are
still used in many oil-based house paints today. But natural
binders quickly gave way to synthetic binders, which comprise
90% of the market today. These synthetic binders include
alkyd (made from acids), celluloid, acrylic, epoxy, and urethane
to name a few.
The pigment and binder dispersion is dissolved in a solvent,
which controls the consistency of the paint and evaporates after
the paint is applied. Without the solvent, the pigment-binder
mixture would be too thick to spread easily and uniformly.
Nitrocellulose lacquer uses a celluloid-based binder. Acrylic
lacquer uses an acrylic-based binder. Both use acetone as their
solvent, which is what defines these products as lacquer.
Acetone is an extremely fast evaporating solvent. That's why
lacquer became so popular. It dries very fast and gives
excellent gloss. Quick drying time is important for production
environments such as car and pinball manufacturing because time
is money.
Since nitrocellulose lacquer uses celluloid as its binder,
there are some problems. Celluloid is the same material used for
movie film, and we all know what happened to those old movies -
they turn to dust with time.
Prior to 1956, all General Motors (GM) cars were painted with
nitrocellulose lacquer (all other car manufacturers used enamels
except GM). GM liked lacquer. It dried fast, looked great, could be
rubbed-out to remove minor scratches and dullness, and it spot
repaired easily. Enamels looked dull in about the same time as
lacquers, but you couldn't easily rub them out to get the shine
back. And the body shops loved lacquer for the ease of application
and drying time. Same for pinball makers; lacquer was an ideal
surface since it could be easily polished, and was fairly durable.
The celluloid-based binder in nitrocellulose lacquer had more
problems because it yellowed and "checked" with time ("checking"
is the term for slight finish cracking due to brittle paint).
There were also problem with color retention (though this isn't
a big issue with pinball playfields, as the colors were silkscreened
in ink, and then clear coated with clear lacquer).
GM wanted answers to these lacquer problems, and they turned to
DuPont. (In 1917 DuPont began buying an interest in General Motors
Corporation and owned 25 percent of the stock at the end of 1925.
In 1962, after 13 years of antitrust litigation, DuPont was ordered
to divest itself of GM stock.)
In 1956 DuPont started using acrylic binders in their lacquer. This
solved the yellowing problem, and to a large extent, the color
retention problem too (acrylic is more UV resistant than celluloid).
Also, since acrylic binders have better elasticity, the checking
problem got much better too. The only down side to acrylic lacquer
is, to some, a myth. That is it never dries as hard as nitrocellulose
lacquer (hence no checking problems). And since it doesn't dry as
hard, it doesn't buff and shine as well (many, mostly in the paint
industry, dispute this, but as a painter I agree). Any old-time car
painter will argue this to the death.
With DuPont's success in acrylics, by 1957 Ditzler and the other
automotive paint companies also started to convert their GM lacquer
paint lines to acrylics. By 1959 all new GM colors developed were
acrylics. Ford and Chrysler colors didn't switch to acrylics till
1962, and Chrysler colors were available in both acrylic and
nitrocellulose into the mid 1960's. Ford and Chrysler cars were
factory painted in enamel, so converting the lacquer lines to
acrylics was less of a priority.
ANYWAY, so what does this have to do with pinball???
The bottom line here is this... If you clear coat a playfield
with (acrylic) lacquer instead of a urethane, there can be
some problems:
Film thickness. You can't spray more than a few coats of
lacquer on a playfield. Well I mean you *can*, but you don't
want to! With lacquer, the more film means the easier the
lacquer will "check" (crack). That's why all pre-1990s playfields
don't have much finish on them from the factory.
Urethane on the other hand, doesn't have this limitation
(well it does, but you would *really* have to heap the
urethane on).
Durability. Heck you're clear coating an old lacquer playfield,
right? Well how did the lacquer wear? Not so good, right?
(or you wouldn't be clear coating it!) Acrylic lacquer wears
well, but it's not as hard as urethane. And you can't put as much
film thickness on with lacquer, which gives it the appearance it
wears even worse!
I guess the thing that sticks out in my mind the most is a
Black Knight a friend of mine bought from Herb Silvers.
Herb did a real job on this game; all black chrome, repainted
cabinet, pimped out to the max! And he clear coated the playfields
in Acrylic Lacquer. Well a couple of years later and how does the
game look? Not so good frankly. Herb sprayed too much film
thickness on the playfields, and the lacquer is starting to check
(though in this home environment, the playfields only show
minimal wear, mostly on the shootlane and common ball paths).
Finish compatibility. Here lacquer really wins. When you spray
lacquer, it is very "hot". that is, it "bites" into the old
finish very well, and really attaches itself. So well in fact,
it really becomes "one" with the original finish. It is a
mechanical *and* chemical bond.
Urethane on the other hand doesn't really do this as well to
a lacquer playfield. The bond is really not as chemical, but
is more mechanical (that's why you have to sand a playfield well
before applying urethane). I mean it works, and it works well,
but the bond is not the same as lacquer.
Yellowing. Acrylic Lacquer is resistant to yellowing, but it
does still yellow! (it is WAY better than nitrocellulose
lacquer though). Auto Urethanes though really don't yellow
much at all; it is much more UV resistant.
What it really comes down is this: do you want to use a 1950s
clear coat product on your playfield, or a 1990s clear coat
product? For me, I like urethane. It's better protection,
and it doesn't check. And I'm a guy that has been spraying
lacquer my whole life, and I *really* like lacquer...
----------
(a lot of the above information came from an article I wrote
about lacquer in 1997).
GoosePimp
--
GoosePimp (StompS)
Portland, OR
http://www.geocities.com/pdxinvestr/Stomps.html
Kerry Stair
--
Kerry Stair
Mantis Amusements
www.mantisamusements.com
<c...@provide.net> wrote in message news:3D550D...@provide.net...
Steve Charland
A question for you since you know a lot about this. What about
furniture lacquer? Specifically MegLacq, for table tops and cabinets. It
can be applied to a thick (a few good coats), durable, smooth glass like
appearance. (not that I intend to use it, it's banned in Ca. now) I shot
a lot of the stuff in the mid to late 70's and was amazed as to how
strong and mar resistant it was. I always thought it would be great for
EM playfields since they don't have a ball pounding them the way SS games
do but I never got around to trying it. -S (CARGPB1)
<a good piece of information snipped to save bandwidth and ask a Q>
c...@provide.net
oh yea i forgot to mention "furniture lacquer"!
"furniture lacquer" is nitrocellulose lacquer most often.
Now I know, you're thinking... "Why would they use nitrocellulose
lacquer on furniture, it yellows!?"
But that's just the point! on furniture, you *want* the
finish to yellow! with age, the item has a "warmer, gentler"
texture and patina due to the nitrocellulose lacquer.
Also like you said, the gloss of nitro lacquer can be
incredible.
And right out of the bottle nitrocellulose lacquer is
slightly yellow. Acrylic clear lacquer is crystal clear.
An example of nitro and acrylic clear lacquer color can
be seen on the video TOP#2, when we are repainting the
woodrails on the EM baseball. I show how yellow nitro
lacquer is, before it is even sprayed.
Acrylic lacquer is good for cars, but basically most wood
products (other than pinball playfields!) are sprayed with
nitro lacquer. There are some exceptions, but for the most
part, this is true.
At some point in the late 1950s or 1960s I'm sure pinball
playfield makers switched from nitro lacquer to acrylic.
But unfortunately i can't find anyone that knows exactly
when that happened!
Bruce
Clay, could you clarify for me. I may be wrong, but it seems as if at
one point you mentioned too much urethene will check? Which is why you
don't reccomend more than a few coats? I'm going by memory, not
doubting your expertise.
Thanks
Arizona Bruce
Cliffy
you respond and especially when you place your replies at the bottom.
Just do a <snip> please? Thanks! ;)
Bruce wrote:
<snip>
--
Cliffy
(CARGPB2)
http://home.attbi.com/~crinear
c...@provide.net
> one point you mentioned too much urethene will check? Which is why you
> don't reccomend more than a few coats? I'm going by memory, not
> doubting your expertise.
> Thanks
> Arizona Bruce
Correct. Too much of *any* coating is bad. But you can put
down more urethane without it checking, compared to lacquer.
Basically just 2 to 4 coats of *any* coating. But since
urethane is high solids, 2 coats of urethane is *way*
thicker (film thickness) than 2 coats of lacquer. Too much
film thickness is the problem I have with the Bill Davis
approach, but that's another thread...
John Dunlap
Thanks for this and endless thanks for your repair guides. I, like many
others, couldn't enjoy this hobby a tenth as much without your help!
After reading the posts on clearcoating from the last two years, I'm
surprised that more people are not attracted to lacquer because it IS the
1950s product. There has been a lot of discussion in rgp concerning
preservation and the value of keeping things as original as possible. I'm
not arguing that this should be the only goal. I'm just surprised that
restoration purists wouldn't consider the look and feel of the playfield to
be an important element of an authentic restoration. Also, regarding
durability, my impression is that most playfields were trashed because they
were not maintained - not cleaned, not waxed, old balls. If a collector
keeps their games waxed the ball doesn't even touch the finish - does it?
Thanks again,
John
New Orleans
<c...@provide.net> wrote in message news:3D550D...@provide.net...
Manic
your words of wisdom.
Bruce <bruc...@yahoo.com> wrote in message
news:395a1a88.02081...@posting.google.com...
Bruce
> Bruce, just tryin' to help ya here... snip long posts when you can when
> you respond and especially when you place your replies at the bottom.
> Just do a <snip> please? Thanks! ;)
>
> Bruce wrote:
> <snip>
Thanks Cliffy,
I know, just wasn't paying attention.
Arizona Bruce
John Robertson
His game NEVER showed any signs of wear. This would be after ten to
fifteen years of play in his arcade - 100,000 plays on any of his pins
was not unusual...good old wax...and of course the balls were in good
condition.
John :-#)#
(Please post followups or tech enquires to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
mailto:j...@flippers.com, web page http://www.flippers.com
"Old pinballers never die, they just flip out."