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In article ,
says...
On Thu, 12 May 2005 20:01:11 +0100, Paul Mc Cann
wrote:

The powder is only a type of paint in a powder form. Its a mixture of
resins and colouring compounds. (i.e.) Paint. It flows out when heated.

Paint is generally taken to mean a liquid, with either a resin which
cures on exposure to air, or a solvent which evaporates. If you want to
term a non-flowing, non-curing, non-dissolved powder as "paint" then you
can of course have words mean anything you like. But that's like Alice
talking to Humpty Dumpty.

I.M.E. powder coating is invariably termed as a type of paint. It is
applied by electrostatic spray on to a surface, stove enamelled and the
finished product pereforms the same function as and is identical to
liquid paint. It is generally applied by spray painters in what are
generally paint shops.

If it walks like a duck and quacks like a duck, its a duck

Its not rocket science any half trained operator can control the
application.

But you need a conscientious operator. Skimping on spray time around the
corners, or fusing it for a bit too short a time to stop glossies, all
improve throughput but they reduce quality.

Any operation needs a good operator. Even brush applied finishes require
a good operator. Applying powder coating is no different, nor is it in
any way dificult to attain good finishes which is one of the reasons it
is often preferred. (i.e.) Its harder to make a crigs of the job with
powder coating than it is with liquid paint. While no great hand at
spray painting I easily obtained a good finish with powder coating the
first time I tried it.

Personally we use several different commercial sprayers to spray and
stove enamel steel frames,

I'm loath to say that "stove enamel" can't apply to powder coating,
because it's certainly stoved, but the name is usually applied to a wet
paint process that's stoved, not powder.

Its a stove enamel finish. Its baked in an oven after application. No-
one I know in the paint industry would call it anything else. Why would
they for heavens sake ? Its baked in an oven. What else would they call
it. Its not worth a tinkers curse unless it is stove enamelled. Unlike
wet paints which can be air drying it is always baked as part of the
process. The term stove enamelled most certainly is not applied only to
wet finishes.

No. Your confused again. Dipping is mereley dunking in paint.

Of course it is. But we're talking about powder coating, not paint.

can obviously dip in paint (your paintbrushes), or in liquid rubbers
(plier handles) or in powder. Shouting "You're wrong, I was talking
about Nutella dip, yah boo" is just playground sophistry.

There was no sophism in what I stated, just plain and simple facts. A
'dipping finish' is generally understood to be in a liquid medium. The
problems you were attributing to what you termed as a dipping finish are
those met with when wet dipping.

And for that matter, you can powder dip either hot or cold
(electrostatically). Hot dip is the one for the thick coatings,
electrostatic dip is the one that can have problems with sharp edges, if
you're too careless withdrawing from the bath (too roughly, too early).

Electrostatically applied coatings excel on edges due to
the nature of the application

Yes, but the flow afterwards tends to reduce this.

This is a problem with all paints and is not peculiar to powder coating

Over stove a powder
coat and the edges thin out as surface tension pulls the coating
inwards.

There you go again. The improper use of any finish will degrade it. The
problem lies in the operation not in the product. The fact that we
talking about powder coating here is fairly irrelevant in this context.

Among the various reasons powder coating is preferred by the spray shops
are primarily its ease of application and its ease of obtaining a good
even finish. All this talk about operator error, poor adhesion, pooor
coverage on corners is just that. Talk. No-one I know complains about
powder coating in these terms. Possibly books make reference to these
things but they are not regarded as problems particular to powder
coating by the trade i.m.e. The main complaint I ever hear about powder
is the cost of the raw material.

--
Paul Mc Cann