You'll need about 25psi. Unlike the siphon-feed jobs, the Bijur doesn't take all that much air pressure or volume. I don't know if your diaphragm compressor would be up to the job, but it might. You'll need only a couple cubic feet per minute.
I've found that, even though the liquid tank is pressurized, it works better if the
tank is at the same level or slightly above the nozzle level.
As for adjusting the mist: most people set the mist level much too high, then complain about their shop getting fogged up. According to the Bijur theory of operation, there should be virtually no visible mist. The cooling comes from the refrigeration effect of the mist evaporating into the airstream.
You can feel this on your finger when it happens. Stick your finger in front of the nozzle, turn on the air, and it will feel like normal air. When the mist works its way to the nozzle, the airstream will suddenly get noticably colder.
Set the mist level so you're just getting a few beads of liquid condensing on your thumbnail when you hold it in front of the nozzle. If you're doing really heavy work you may want to crank it up a little, but don't overdo it.
You may find that it takes a minute or two for the mist to get going; that's my only complaint with the Bijur.
You'll also find that the inside of the tank tends to fur up with crud after a while, and will need cleaning. That's just nature of coolant systems in general though, not anything specific to the Bijur.
You may be able to find more information at http://www.bijur.com. Search for FluidFlex, and/or give them a call. They've always been helpful to me.
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