Help using Modelflex paint.
Greg McCartney
given up long ago, but it is the principle of the matter now (probably that
slogan that says even a beginner can use it).
First question. Why does the modelflex paint flex paint seem to spatter
onto the model instead of evenly flowing onto it? I get the appearance of
speckled bits of paint no matter what settings I use on the air brush.
(BTW:: I believe I am using the recommended 27-30 lbs of pressure.)
Second question. On occasion the paint seems like it has a high surface
tension and collects up into little puddles giving an orange peel affect
when dry. Again in this situation the paint does not seem to lay on the
model surface or go on smooth. This can occur on the first few passes even
at the lightest spraying settings. (A similar affect happens if you
saturate the model with paint by over spraying, but over spaying is usually
not the case.) Why does this happen?
Third question in general about painting. What causes the paint to be
brittle and easily scratched off of the model? This happens to me almost
every time. I have tried bathing the model in alcohol before spraying it
to remove any mold releasing agent but it still scrapes off. I usually
have to strip it with break fluid and repaint the first coat without any
problems. Both oil and waterbase paints have done this.
What can I do to prevent the above conditions? Any advise would be
appreciated.
Greg
Andy Harman
wrote:
>What can I do to prevent the above conditions?
Use Scalecoat II :)
Modelflex is actually one of the better acrylics out there. You
didn't mention what type of airbrush you are using, but if it works it
shouldn't matter too much. Modelflex doesn't really need much
thinning, and it has *terrible* shelf life once opened. If you are
spraying out of a bottle you have used before, throw it away and start
over with a new bottle. I have gotten good results _only_ when
shooting a brand new bottle. Same bottle, merely a week later, gave
me a sandpaper finish.
There's much more, you may want to do a DejaNews search on Modelflex,
acrylics, and even Accuflex. Modelflex doesn't have the same "time
bomb" problems that Accuflex had, but some of the issues are the same
regarding technique. I've found that with a good bottle of paint,
it's not rocket science... with a bad bottle, even Werner Von Braun
couldn't get a decent finish <g>.
Andy
Visit the Prototype Modelers Group Web Page at http://w3.one.net/~aharman/index.html
Sorry I must resort to anti-spam practice, reply to aharman at one (spelled out) dot net
Jerryglow
>Second question. On occasion the paint seems like it has a high surface
>tension and collects up into little puddles giving an orange peel affect
#1 You may be using too fine a tip on your airbrush. I changed from a Pasche V
with large tip to a VL with the finest tip and get better results.
#2 and this may be related to your problems in #1, it's water based which is a
large molecule hense the surface tension. I use a few drops of alcohol as
thinner or added to denatured water.
Jerry Glow
Train Detail Works
Brea CA
"It ain't a model until it's painted"
Tony Burzio
Greg McCartney wrote:
> First question. Why does the modelflex paint flex paint seem to spatter
> onto the model instead of evenly flowing onto it?
Not enough water. Try a bit more tothin out the paint. Also, if your needle
is not far enough forward, you won't
get enough aeration in the outgoing
paint. Ideally, the paint should come
out so light that it takes about 10 or
so passes until you can actually see
the color on the plastic...
Try this method: Put the fine point in
the air gun. Use the paint cup
(the thingy that looks like a pipe for
tobacco) instead of the bottle in the air
gun for all spraying. Put a 1/4"
of paint in a small bathroom size Dixie
cup. If there are any goobers in the
paint, or if the water has separated out
of the Latex (good paint should pour
like cheap Maple Syrup), then throw out
that bottle and bitch at your model shop
for selling you bum paint (too old or they
allowed it to get hot). Put a bit of water
in another Dixie cup. Squeeze the water
cup to make a spout and pour about 10
or so drops of water in the paint Dixie
cup. Swirl the paint and water mix around.
This should look and behave like chocolate
milk. Put the metal pipe into the air gun
and put 1/4" into the pipe. Spray at a white
piece of paper. If you have enough water
in the paint, you should get a fine spray that
looks like a perfume sprayer (visit a department
store to see what this should be). If you
spray your models with this thin of paint, the
paint should be dry about 3 seconds after
it hits. Too dry too fast and it won't stick,
too wet too long and you get orange peel paint...
I paint outside, and when it is a bit windy
the spray doesn't reach the model because
it blows sideways as it comes out of the gun.
Try and get your paint this wispy.
> Second question. On occasion the paint seems like it has a high surface
> tension and collects up into little puddles giving an orange peel affect
> when dry.
Sounds like my Chevy :-). You are too faraway from the model and the paint is dry
when it hits. Also, don't paint it sooooo
thick. Several coats may be needed
to cover bright colors. The paint shrinks
as it dries, but too thick and it looks like
old skin...
> Third question in general about painting. What causes the paint to be
> brittle and easily scratched off of the model?
Too thick. This is not Rustoleum (tm).. :-) Thebrake fluid is scratching the surface to allow
the goobers to stick...
The first thing to do when learning to
paint is to learn to weather. If you can
spray on a fine mist of dirt across a
color without getting an oatmeal splat
effect, then you can also paint solid
colors on your best brass...
Tony Burzio
San Diego, CA
Paintloco
>speckled bits of paint no matter what settings I use on the air brush.
>(BTW:: I believe I am using the recommended 27-30 lbs of pressure.)
I use a double action Pasche with a #3 tip and 33-38 lbs of air. It goes on
smoothly. I find that too little air causes the problem you describe. Be sure
to put out only a little paint at these pressures.>Second question. On
occasion the paint seems like it has a high surface
>tension and collects up into little puddles giving an orange peel affect
>when dry.
Sounds like inadequate surface preperation. Use Dawn dish detergent and HOT
water with a tooth brush to clean plastic. If painting brass or white metal
etch in viniger for 5 minutes before washing. If spraying yellow or other fussy
color, prime with model flex primer grey or other high pigment primer. Ude a
hair dryer to dry between coats.>
>Third question in general about painting. What causes the paint to be
>brittle and easily scratched off of the model?
This does not happen when item is clean and paint is properly applied.
Don Murphy
TBO
> #1 You may be using too fine a tip on your airbrush. I changed
> from a Pasche V with large tip to a VL with the finest tip and
> get better results. #2 and this may be related to your problems
> in #1, it's water based which is a large molecule hense the
> surface tension. I use a few drops of alcohol as thinner or
> added to denatured water.
The surface tension is a normal property of the polymer paints.
When it bubbles up or seems to have a "high volume" don't panic.
Using a simple hair dryer will speed the evaporation of the
carrier (water) and the paint will hunker down to the surface.
I use a Paasche H with #3 tip at 32-40 pounds. I can only spray
small amounts of any water base paint at a time -- about one
car side's worth. Then clean it out, and spray again. I always
use paint cups rather than spray from the bottle. Use a very
fine mesh filter to remove the particles from the paint. These
form quickly once the bottle has been opened. Spattering is
caused by these particles, or by dried paint on the tip or
clogging the nozzle, period.
High heat and/or humidity can affect these paints too! (More
of a problem with Accupaint, which sucks water out of the
air.)
Tim O'Connor
toco...@avici.com
Jack Curry
I have come to the conclusion that this is my biggest problem. The lighter
colors just take too many coats to cover a darker base.
Jack
Paintloco <pain...@aol.com> wrote in article
<199807131032...@ladder01.news.aol.com>...
Lots of sniping.
> If spraying yellow or other fussy color, prime with model flex primer
grey or other high pigment primer. Use a
> hair dryer to dry between coats.>
>
> Don Murphy
>
Dann J. Flesher
The problem of poor paint adhesion is often oil...from the manufacturing
process (release agents for plastics), from your hands, from tools, working
area, or even from the plastic molds. Or, horror of horrors, it might be from
a silicone hand lotion or other silicone source.
Try aproduct called Brush Up!. Just brush or spray on a thin film, give it a
minute to work, then water rinse and air dry. It removes all the oils,
including silicone. There is a Brush Up! web page at
<<http://www.norworks.com>> You can buy online or at local craft stores in the
US...the ladies are ahead of us on using this stuff, only a few hobby stores
carry it. It cleans thoroughly and gives a "tooth" to plastic surfaces which
makes them easier to paint.
You should keep Brush Up! around anyway, just to keep your airbrush and regular
brushes thoroughly clean and in shape. It works to remove (not disolve) all
paints: oils, enamels, acrylics, even removing DRIED acrylic from brushes, and
minimizes airbrush teardown.
Dann
Greg McCartney wrote:
> I am about to pull my hair out trying to use this paint. I would have
> given up long ago, but it is the principle of the matter now (probably that
> slogan that says even a beginner can use it).
>
> First question. Why does the modelflex paint flex paint seem to spatter
> onto the model instead of evenly flowing onto it? I get the appearance of
> speckled bits of paint no matter what settings I use on the air brush.
> (BTW:: I believe I am using the recommended 27-30 lbs of pressure.)
>
> Second question. On occasion the paint seems like it has a high surface
> tension and collects up into little puddles giving an orange peel affect
> when dry. Again in this situation the paint does not seem to lay on the
> model surface or go on smooth. This can occur on the first few passes even
> at the lightest spraying settings. (A similar affect happens if you
> saturate the model with paint by over spraying, but over spaying is usually
> not the case.) Why does this happen?
>
> Third question in general about painting. What causes the paint to be