Airbrushing, masking, and Frisket

1) Someone please explain to me why I'd want (and what is) a double
action
airbrush over a so called single action one? What other features should
I
look for in an airbrush/compressor? I want to buy a good one. 

2) Frisket - where would I find these sheets? Art supply? Drafting? Some
other place?

3) Masking - one way to get mask off without the paint that may be
attached
is to run your exacto carefully along the edges prior to peeling, thus
slicing off any paint and preventing "pickup" of paint from the model.
Now,
in less-than-flat areas, this is non-trivial, but on larger flat areas,
it
is a viable technique. I just don't bother masking anymore... too much
pain,
too little gain. Paint more carefully. <Hard with an airbrush>

4) Airbrush paints - Must I buy a whole new set of paints? I have Tamiya
and
Humbrol and Ral Partha paints galore... must these be added to with
another
whole set for an airbrush? Or is thinning and using them an option? If
so,
how much to thin, or with what? 

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alea iacta et pessimo	|  Thomas Barclay
resulto factura est	|  Software Specialist 
------------------------|  Defence Systems
ave, Caesar!		|  xwave solutions
te morituiri salutimas	|  www.xwavesolutions.com
			|  v: (613) 831 2018 x 3008
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