Compressor info

Something funny has happened with the DeVilbiss name. It was once a guarantee of a quality machine, but in the past few years it has found its way onto a variety of cheap crappy machines, while the industrial, heavy duty units have changed their names to DevAir. DevAir industrial units are built in Toledo,or were, while the DeVilbiss Air Power Co. is based in Tenessee. I can't guarantee if this particular model is a good'un. Check a few things. IS it aluminum? With a few exceptions (Champions most notably), aluminum pumps are garbage, and parts are inexplicably expensive. It it running off a 3450 rpm motor? If it is, they are trying to make cfm by going full tilt. Fast running compressors are ok if they are designed correctly,(Emglo dirct drive, Fiac, Fini), but in my experience (compressor mechanic)most are prone to emptying their sumps of oil and running hot when used heavily. 5hp is a lie for anything that can run on household, single phase 220v service. 3.5 hp is about as heavy a draw as you can use at home. Check the wattage of the motor. 1hp = 746w. It may be a decent machine, but just don't expect 5hp (20cfm @ 100psi @ sea level) worth of air. An oil lubricated is superior to any oilless compressor, no matter how cheaply built. I hate to sound like a broken record, but a Campbell Hausfeld VT series vertical twin, cast iron compressor is about the best unit I have seen for an economical, household compressed air unit. I have re-ringed units from 1972 that were still in pristine condition due to proper maintenance. Beware, however, that these too are sometimes advertised as 5hp units. In this hp range, get used to being lied to. A good rule of thumb, 1hp will give you 4cfm MAX! Other good brands are Ingersoll Rand, Gardner Denver, Quincy,Curtis, Saylor Beall, though they will likely be more expensive and usually available through compressor dealers. You get what you pay for.

You would really need to know the cfm required by the gun, and the cfm that the compressor puts out. HVLP by its very design requires lower than normal pressure than a siphon type paint gun,which works in your favour.I have used both types of guns and I like the HVLP best. There is so little overspray that you are almost tempted to not wear a mask or respirator (don't do it). We use one at work that runs off a little box like a small vacuum cleaner operating in reverse, can't be more than a few psi. Rememeber that painting seldom requires full time air delivery. It is usually a bursty type of demand, which gives a compressor some time to catch up, another point in your favour. A 2hp machine should give you about 8cfm under ideal conditions at 100 psi. The lower the pressure you run at, the more cfm a compressor can deliver, within reason. Another tank only helps if the compressor is delivering more air than is being demanded. I run across this a lot in industry. Someone is running at the maximum capacity of their machine and they think another tank will solve their problems. But if the compressor can't meet demand already, when will it have the time to fill another tank? Another tank just becomes a very wide piece of pipe under these conditions. Extra tanks work well for irregular, large air pulse demands, when the compressor has enough excess capacity to fill them. After you use the first charge of air, you will simply have to wait twice as long for your compressor to fill two tanks instead of one.
Perhaps, if I ever remember, I will bring home my Ingersoll Rand condensed air power book and show everyone how they can measure the air delivery of their compressors with and pressure gauge, a pipe tee, and a pipe cap or plug with specifically sized orifices drilled in them. Bye.

Seems like you have the funds for a good machine there. If you have the power to run a true 5 hp machine, and I am assuming you are in the US, I think you could probably get something quite sturdy and reliable for $1500-$2000. If it were me, and I was buying a compressor for myself and power was adeqate, I would go for a Champion 5hp compressor on a 60 or 80 gallon tank. The pump is an R-15. Champions are distinct in that the cylinder head is not a removable part from the cylinder, like a Lycoming aircraft engine. Pistons have conical crowns and the compression chamber is also conical. No head gaskets to blow. Valves are easy to remove and replace. They are aluminum pumps with pressed in liners and they last a long time. They also run very cool. I had a 10 hp Champion running full tilt and I could comfortably lay my bare hands on the cooling fins of the cylinders. They are also fairly slow running pumps and give good cfm. Our wholesaler out east claims 23 cfm, and he says Champion tends to rate their pumps conservatively.Champions tend to be fairly quiet running as well. I think Gardner Denver bought out Champion a little while ago, so you may find them labeled as such. This all assumes you have the power to run an industrial quality machine. I would stick to horizontal tanks, if space is not a problem. Servicing is much easier and the units are less top heavy. A somewhat lighter duty unit that still gives good air, would be a 5 hp compressor built with a Chinook pump. These are Italian reed valve, aluminum crankcase and head pumps with a solid cast iron block. They run cool, give good air (18 cfm) and last pretty well. They are 2 stage so they should give you all the pressure you need as well (up to 175 psi). They run somewhat quicker than most pumps, a bit over 1000 rpm I think. Quincy makes a less expensive line of compressors with the QT series of splash lube, reed valve units. They are worth a look. IR is making some decent cast iron, affordable compressors, but, those of us in the trade see that they are using 3hp pumps running at 1400rpm to make their entry level 5hp. And 5hp pumps turning at about the same speed for their economy 7.5hp units. I have limited experience with them, so I will reserve judgement. They do seem to run smoothly, if quickly, and noisily. IR cast iron pumps tend to last a very long time, but in this configuration, who knows? CFM will always be limited if all you have to work with is household current. 1hp = 4 cfm. 3.5hp being a reasonable limit to what you can get from a household service, 10-12 cfm is about the best you can hope for. If, however, you have industrial service, or 3 phase power ( am I dreaming), then 20-23 Cfm is within reach for a 5hp machine. I don't know what power you are working with, so these compressor units may be bigger than you can run. If cfm is more important than outright pressure, get a single stage. If you want more pressure, get a 2 stage. Most people I talk to need more volume than pressure. 2 stage compressors are more efficient, power wise, when operating at higher pressures. Compressors will always run on and on if you are using as much air as the compressor can deliver. Something to consider. If you are in a rural area, could you run a small gas or diesel powered portable? Sometimes you can get them pretty cheap at industrial auctions. A small rotary vane compressor would be neat too. Quiet and smooth running. A Hydrovane or a Mattei. Sorry for being so long winded!

Sounds like you would have plenty to run a true 5hp, and maybe even a bit bigger. We have a 100 A 3 phase service into our shop and can test up to a 40hp compressor. I guess you'll have to do a little research to see if you have enough spare service to run it, but it sounds like you do. An electrician would be able to tell you that, maybe even over the phone. I doubt every last machine you have runs at 100% all the time so there is probably more reserve than you think.I'd be tempted to put in the biggest compressor I could run/afford. You never know when your excellent work will result in a flood of new customers and a need to expand. Go to www.championpneumatic.com. Look for the specs on the R Series splash lubricated units. The models are designated as follows H or V for horizontal or vertical tanks, R for R series pump, the number next is the hp, and the last number is the size of the tank in gallons, divided by 10. So, an HR5-80 would be a horizontal 5hp splash lubricated pump on an 80 gallon tank. Notice the rpm's that the pumps are running at. Nice and slow! Also notice however, that the 5hp R15 pump is also used as an entry level 7.5 hp pump as well, so everyone does it to some extent. The next pump in the line is a v-4 unit, which is really a 10hp pump, an R-30, which is a bit expensive to build up as a slow running 7.5hp unit. Even at 7.5 hp, though,the R-15 is still running much slower than most cheapy 5hp compressors. Note, you will need Adobe Acrobat reader to view these pages. Try going to the spec sheets and see if they give you Adobe right there if you don't have it.I am by no means saying either, that there aren't excellent machines available from Quincy, IR, Curtis, Saylor Beall or any number of other companies in the US. I do not work for Champion. I do know that they work well and are priced reasonably. For heavier duty service, you can also go to a pressure lubed PL series machine, but they are quite a bit more money. Do some research on machines from other companies to price compare. By the way, you will need a magnetic starter for a real 5hp machine, and probaly a disconnect or breaker installed, so remember to budget for these items as well. If you are going to put the unit into a seperate shed. Make sure there is adequate airflow to evacuate the hot air when the compressor is working. Always exhaust air form the shed, do not blow air in. All you will do is slightly pressurize the shed and have a stagnant pool of hot air inside there. It is a common error when people do their own ventilation. There is often an auxiliary contact on the side of many magnetic starters that can be used to control other devices when the starter is activated. You could perhaps wire an exhaust fan to this that automatically starts with the compressor, and shuts off when it does. Alternately, you could have the fan thermostatically controlled. Position the fan in the room so it drags the hot air off the pump in co-operation with the natural airflow from the blades on the flywheel. That is, don't have the fan sucking air from the front of the pump, when the flywheel blades are trying to blow air back over the pump. Ensuring that the compressor is turning the proper way is crucial! We recently had a compressor fail after only 2 months because the owner installed it himself and had the rotation backwards. It ran too hot and seized. Be sure to put a filter on any opening that admits cooling air into the shed, something like a furnace filter to help keep the operating environment clean. Pollen and such can make a real mess when mixed with even the slightest oil leak. Also do not forget to leave enough room around the entire compressor unit to allow for any service or repairs. This is my own pet peeve! I have once been forced to stand on a wooden platform about 3 inces larger all around than a 60 gal DeVilbiss compressor that was dangling from a ceiling by 4 3/8 ready rods. And not solid rods either, about 4 rods per corner, connected by coupling nuts, bolted to the roof girders. Swinging away like Tarzan. I wondered if any of those rods were in by a half a thread!:-). Resist the temptation to put a compressor up high. Out of sight, out of mind. And when it eventually fails because of no oil changes for 8 years, it is some poor schmuck like me who has to put on the moutaineering gear and go and get it! I always laugh when I go into a shop and see the amount of work put into a platform to raise a compressor up from floor level. Why? To save floor space. Funny, there never seems to be anything under the compressor..... ..
It is hard climbing a ladder with 80lbs of tools, and a real workout to go back down every 5 minutes to get the tool you forgot last trip! Be sure to allow for some kind of easy access to drain condensate from the tank as well. I have seen tanks with as much as 20 gal of water in them because they were never drained. Tanks can rust through quickly if neglected. Something as simple as putting the compressor on a pallet can give you a few extra inches of clearance for this task. If I were doing this install, I would put in a timed electic auto drain. They aren't terribly expensive and do a good job. Drain the condensate outside of the shed. Oily water ruins wooden floors. Remember that it is not always summer as well! You should put some form of heating device in there in the winter, as compressors do not relly like operating at freezing or below freezing temperature. Drain lines can freeze up as well,and due to the start-stop nature of compressor operation, pumps operating with heavy, thick oil will wear quickly, especially wrist pins and bushings. Don't use uncovered fiberglass insulation, as it tends to fall apart and do the same thing I warned you about with pollen, a real mess. Fiberglass covered in some kind of vapor barrier or styrofoam would be best. Allow for some kind of disconnct for the cooling fan as well, a simple light switch would do.
Well, that is about all I can think of right now. Now that I have spent all of your money, you better get busy welding!