Originally Posted by strsout
what exactly would be the advantage (or not) of an oilless compressor?
Elton, if you remember the little compressor I bought to the service party at your house, it was my daughter's Sears Craftsman, about $90. It would be just fine for the uses you mention. It will even run an impact wrench for short times, as long as the pressure is given time to build back up between uses. The CFM ratings are steady state that the compressor will supply to the tank. However, the CFM output fom the tank to the tool is as high as the hose and fittings will allow for a short time until the pressure drops too much for the tool used. Remember, we tried the impact wrench on Buck's swing arm pivots, but had to get a 4 foot pipe to break that one loose. Unless you plan to do something which requires high CFM for a longer time, such as painting, just get the small one.
Oilless is OK for home use, but the larger oiless compressors are noisy and pretty low CFM for the horsepower rating. I have a 2HP Craftsman oil type that has seen pretty heavy use for about 30 years! The tank is starting to rust out now, so I will be looking for a good 3-5 HP vertical OIL TYPE unit next.
Beware anyone looking for compressors now, for some stupid reason the manufacturers of consumer ones got into a HP war, and now are rating them at "PeaK" hp. That is a huge rip off, as it is meaningless. Don't understand why they are allowed to label them this way. If you want a certain HP compressor, be sure it is steady state rated. One clue is that one horsepower is 746 watts, supply will be more due to motor efficiency, so check the motor nameplate rating for amps, multiply the voltage by the amps to get watts, then divide by 800 to get approx. steady state HP.
Another clue, one horsepower of compressor should supply about 4 CFM steady at 90 PSI to the tank. A true 2 HP compressor will be rated at around 8 CFM at 90 PSI.