An artist friend of mine uses bottled nitrogen instead of a compressor for all of his airbrush work - no moisture problems, no filters necessary. For occasionally dusting off optics, this may not be practical, but if one is considering a compressor, do as Chuck did and install the appropriate filters. -----Original Message----- From: utah-astronomy-bounces+kimharch=cut.net@mailman.xmission.com [mailto:utah-astronomy-bounces+kimharch=cut.net@mailman.xmission.com] On Behalf Of Chuck Hards Sent: Monday, May 07, 2007 9:32 PM To: Utah Astronomy Subject: Re: [Utah-astronomy] dirty lens Don's right, a blast of air is only good for removing loose dust. Once the optic has been exposed to any humidity, the dust must be loosened with liquid. I stopped buying canned air two decades ago. Bought a 5-horsepower compressor, stuck it in my garage, ran a line down to my basement workshop so I can use various airbrushes, sprayers, and pneumatic tools. Installed a filter to remove oil and particulate contaminants and a dryer to remove water vapor, followed by a secondary filter. In this instance, the only thing I have to watch out for is too much pressure when dusting-off alumnized surfaces- at 120 psi there is a real chance that the coating could be blown right off the glass, if it had adhesion problems to begin with...I use a regulator as well.* * On 5/7/07, Don J. Colton <djcolton@piol.com> wrote:
I would avoid compressed air since the cans contain a slight amount of fluid that can damage coatings the following is from my previous link:
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