On Tue, 21 Jan 2003, Jay West wrote: Get a diaphram (vice piston) compressor. The only way it can have oil in the output is if it is purposefully introduced. - don

There are oil extractors that remove oil, water, and down to .5 micron particles. You'll pay for such filters. SCUBA tanks are actually a decent way to go, with a $100 or so initial expense. You can buy used 80CF tanks for $25 or so. These can be refilled for about $8 at any SCUBA shop. You'll have to get periodic visual inspection, and a hydro test every 5 years or so. Buy a used regulator through your local newspaper or sellers magazine (we have one that comes out every Tuesday that's several hundred pages). 80CF will go a long way, assuming you don't just get down on the nozzle and let it run. And it will be very clean and pure. Our dive shop has a massive filtration system. The other reason, by the way, that divers don't fill at the local gas station is you can't get 3000PSI, and the risk of carbon monoxide and such getting into the tank. At depth, that stuff will kill you faster than licking 220VAC mains. Most dive shops use electric compressors, and they have extractors for CO on them. There are some that use gas for portable fills, but they have carefully managed exhaust and intake systems. You can also buy bottled Nitrogen at your local welding shop. This isn't very cost effective, however. They charge about $20 to refill my 40CF Argon bottle for my solder paste dispenser. Nitrogen is cheaper, but they still have a minimum fill fee. I think it's around $10. And because the bottles have to be trackable, you'll either have to buy or lease from them, or keep up with your paper work. Purchase for my 40CF Argon bottle was about $70, filled, IIRC. The SCUBA tank is actually the most viable if you need portable air, too. You can buy a backpack harness for next to nothing, which makes a convienent carrying handle. SCUBA is accepted for transport everywhere, including through tunnels (unless it's changed, welding gasses are not. Or maybe it's just the flammable or oxidizers, dunno). And in most towns, it's easier to find a dive shop than it is a welding supply store. And the dive shop people are often friendlier. --John

You might also consider getting one of those automotive air tanks - you know the kind that you fill at the gas station (or from your own compressor) and keep in the trunk of your car to fill tires.. These go for about 20$ starting at 5to 20 gallons. These are just small compressor-like tanks- not the 12v tire compressors (which could be very handy fill them indoors if you don't have a compressor at all - and they go for 10-20$). These already have a "tire" type filler valve, regulator, pressure gauge, coiled plastic flex hose, and cleaning nozzle. Perfect for touching up pain scratches etc when used with an airbrush.. Another alternative might be those pressure canisters for fountain pop dispensers - good to 120psi only, but you'll have to buy the regulator, hose etc. I considered refilling an old extinguisher bottle, or spent propane (small welding cylinder) but changed my minds after reading all the warnings and threats of imprisonment for doing so. I would have preferred a more portable thermos flash sized unit, bit opted for an under-bench automotive air tank. I still loathingly buy the pricey, noxious, smelly pseudo-chloro-flouro "compressed air" cans sold for computer cleaning.. but now with the tank I'll be using them less. Those canned fumes can't be very healthy for you- read the warning on the can about using in a big room, heart attacks etc.. h

John Lawson wrote: Why so low? If I'm using a compressor, I usually set it to 80psi. No problems yet! I'm not exactly cleaning core memory though. Side relief hole.... non of those either :-) Chad Fernandez Michigan, USA

J.C.Wren wrote: It's so you can't blow air through your skin into your blood stream, by holding the end against some body part. Chad Fernandez Michigan, USA

Hi, Years beliefly had air cans. They made me feeling ill so I refused to use them afterwards. At former computer shop, they had pair of small vaccum cleaners (looks like oversized liquid laundry containers) that you can lug by it's handle but they were designed to vaccum or exhaust via hose. For it's size they were powerful enough to move heavy built up dust out. I think it was blue or green, made by Panasonic, it was long ago around 90-92 timeframe. At current TV shop work, we have heavy-duty air compressor and 1/2hp vacuum w/ flex 4" dia hose. Other tech used air to blow dust all over, I used both tools to blow off dust and trap dust with vac to cut down on dust floating around. Worked well. One thing, compressor is LOUD. Hissssss, clunk clunk chugg chug chug goes on for few minutes then with a clank, stop pumping up. That 1/2hp vac, is rather noisy too. More like roar actually. Both TVs & monitors attacts BIG heaps of dust by static action that is part of HV process. Cheers, Wizard

The dive shops also sell some smaller and more convenient size tanks for portability. A 30 cubic foot tank is really easy to handle. They charge the same to fill a 30 as an 80 though. There are even smaller tanks too. Some day I plan to make a fill adapter to fill my 30 myself from my 80's. I'll have to be careful with that though. Fill very slowly to avoid heating which is one of the reasons they set the tanks in water when they fill them. Perhaps if the fill rig had a couple of small orifices by each tank, that would restrict the fill rate for safety. One of the dive supply catalogs used to list a tank transfer rig, but I could never actually find it. High pressure gasses can be very dangerous, so they may have stopped selling them. At 11:39 AM 1/21/03 -0500, you wrote:

On Tue, 21 Jan 2003, J.C.Wren wrote: Never been to West Texas, have ya? :^) Doc

Fred Cisin (XenoSoft) wrote: ShopVac makes a Micro Cleaning Kit that fits a 1.25" hose. It consists of small brush attachments and an adapter to the 1.25" hose. The brushes can vacuum debris, but when the ShopVac is in reverse operation, the adapter reduces the hose outlet to about 3/8" - this produces the velocity needed to clean boards, fans, etc. See: http://www.shopvac.com/dev/catalog/detail.asp?id=221 Still distributes a layer of dust on all things horizontal. Martin