Adam , 
It all depends on the nozzle orifice size and shape, as well as the viscosity of the material. In most catalogs you will see a series of pressures that are used for testing purposes. Spray systems has a great tutorial that explains nozzle science a bit better. To answer your question 8 psi is do able with a very small orifice, the issue then will be impingement force, area of coverage, distance from work. All of which may or not be issues depending on your application.

If I can help you with some specifics, feel free to drop me a line 

Russell Smith
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-----Original Message-----
From: Adam Seychell [mailto:[log in to unmask]]
Sent: Wednesday, October 08, 2003 8:16 PM
To: [log in to unmask]
Subject: [TN] spray nozzle pressure


In the world of spray etching equipment, what is the minimum
spray pressure generally accepted before the quality of the
etching becomes degraded (assuming the nozzles still hold
the spray pattern) ?
I have heard of pressure ranges between 15 psi and 40psi (1
to 3 bar) being used. Does anyone know if a pressure of 8
psi (0.55 bar) can be practical ?

Adam Seychell.

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