The "Pascal" is the SI unit for pressure. MPa is a MegaPascal or 1,000,000 Pascal
1Mpa is about 145 PSI in American units. Or more accurately 10 Bar On Fri, Feb 15, 2019 at 5:48 PM Gene Heskett <ghesk...@shentel.net> wrote: > On Wednesday 13 February 2019 05:41:38 Gene Heskett wrote: > > > On Wednesday 13 February 2019 03:46:53 Les Newell wrote: > > > I recently made a couple of coolant units based on eBay mister heads > > > like this one > > > <https://www.ebay.com/itm/Mist-Coolant-Lubrication-System-Spray-for- > > >8m m-Air-Pipe-CNC-Lathe-Milling-Machine/172271983174?>. These ones > > > with the straight end on the nozzle seem to be better quality than > > > the ones with a nozzle that just tapers down to a blunt point. The > > > problem with all of these eBay misters is that they generate a fine > > > mist, which gets everywhere. I made some modifications on mine to > > > work around the problem. The air jet in the model I linked above is > > > just over 2mm diameter. I extended the oil jet using 2mm stainless > > > tube so it now sticks out about 1.5" past the end of the brass > > > nozzle. This leaves a thin annular gap for the air to get out. As > > > the area of the air jet is now very small you can run quite high > > > pressure (60 - 100 psi) with very low flow. By the time the air > > > reaches the end of the oil jet it has slowed down a lot and no > > > longer has the energy to break the oil into a fine mist. You end up > > > with a column of air carrying a stream of droplets in the middle. On > > > alu oil consumption is minimal. I use a neat cutting oil and my > > > previous tank was the filter bowl on an air regulator. That was > > > enough for several days of machining. > > > > > > One down side of this setup is that it won't suck the coolant up > > > from the tank. I used a filter canister as my reservoir. Shop air is > > > supplied at full pressure to the nozzle through a solenoid valve. > > > There is a tee in the line which feeds a regulator to drop the > > > pressure to ~10 psi for the reservoir. Theoretically those filter > > > canisters can take 100psi but that sort of pressure in a plastic > > > tank scares me. > > > > > > By the way Gene, if you are buying a solenoid valve from eBay, get > > > an Airtac valve. They are available in a wide range of voltages and > > > configurations. They are reasonably well made and can handle 100% > > > duty cycle. > > > > > > Les > > > I found a 12 volt 1/4" version, but what the heck is > Operating pressure 0.15~0.8MPa supposed to tell me??? Need a translation > from chinglish please. I haven't a clue what the heck 0.8MPa means. > > > > So I probably bought the wrong one. Expertise comes from the > > experience of doing it wrong. :) > > > > > On 13/02/2019 01:31, Phillip Carter wrote: > > > > I use a water filter canister similar to this: > > > > https://www.cnczone.com/forums/uncategorised-metalworking-machines > > > >/1 02934-built-fog-less-coolant-mister.html > > > > <https://www.cnczone.com/forums/uncategorised-metalworking-machine > > > >s/ 102934-built-fog-less-coolant-mister.html> > > > > > > > > Cheers, Phill > > > > Cheers, Gene Heskett > > > Cheers, Gene Heskett > -- > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
