"orange peel" and dope

[Michael Horowitz]

when applying buty.dope over a previous coat, one can get an 'orange
peel' effect. I see it mentioned on the Web, but no description of
what's actually happening.
Anyone know the answer, prevention, and recovery from the effect
(assume a 2 in. area)? - Mike

[larsen-tools]

"Paint & Body Handbook", HP Books/ www.penguin.com........... is the best
painting book I've found. Although written for car painters most of its
content also applies to planes or refrigerators, etc. .
ALL kinds of paint & techniques are covered - it is very detailed.
What's quoted below should apply to all paints.
I hope this helps...........

Ch 8, Paints & Painting Products
P-94 .....(Acrylic Lacquer) .... "Orange peel is the effect paint displays
when, instead of flowing out level, it tends to dry bumpy, similar to the
surface of an orange."

".... use of lacquer and thinners that have varying evaporation rates. By
thinning the lacquer with a medium- or fast-evaporating thinner for the
first two or three coats, color may be applied one coat over another with no
drying time in between. The final coat is thinned with a slow-evaporating
thinner. This allows the lacquer to flow-out, nearly eliminating the
orange-peel effect."

Ch 9, Painting Equipment & Techniques, P-114
Technique- Spray guns are designed to give the best performance when held
eight to 12 inches from the surface to be painted. If held closer, air
pressure ripples the fresh paint. Hold it farther away and the paint will go
on too dry, causing orange peel or dry film. It will also affect the color.
A slower-drying thinner or reducer will allow more leeway in spray-gun work.
It will, however, cause runs when too close and excessive over spray when
too far away. Try to maintain the 8- to 12-inch working distance."

EAA, "How to Paint Your Own Airplane" by Ron Alexander, P-66
"Orange peel is usually caused by the spraying pressure being too high or
because the paint itself has been mixed incorrectly with not enough solvent.
Different temperatures and humidities will require different thinners and
retarders. The wrong mixture will contribute to orange peel. An amateur
painter can also cause orange peel by holding the spray gun too far from the
surface. One last possible cause is using the wrong size air cap or fluid
tip."

"Michael Horowitz" > wrote in message
...
> when applying buty.dope over a previous coat, one can get an 'orange
> peel' effect. I see it mentioned on the Web, but no description of
> what's actually happening.
> Anyone know the answer, prevention, and recovery from the effect
> (assume a 2 in. area)? - Mike
>

[jmk]

Question: When you say "previous coat"... previous coat of Buty? Lots
of these things don't like to go over other formulations. For example
(to use regular commercial paints) Krylon and Rustoleum *really* do not
work and play well with each other. Both are fine paints, but spraying
one over a coat of the other - even one that has dried for days - will
almost instantly produce orange peel.

Recovery? Only one I know is fine sanding (vary carefully, in your
case) and re-prime/apply.

OTOH, if you are talking about multi-coats of the same formulation,
then see the other suggestions posted.

[StellaStarr]

Richard Riley wrote:
ng just the right overlap and drift too close, and get a run.
>
> About the same time I was reading about the "Dambusters" dropping the
> skip bombs in WW2, and how they had to drop from exactly 60 feet.
> They put 2 spotlights on the plane, angled toward each other, that
> would converge exactly 60 feet under the plane.
>
> So I got 2 small AAA powered lasers at Fry's, glued them to the gun
> and pointed them to converge at 10 inches. Once I got used to it, I
> can hold 9-11 inches easily without the lasers.


What an elegant solution! Bravo!