Air Compressors - mainsplain

[FAKKY]

Originally Posted by Dead Parrot

Quick way to consider air compressors:
The tank is the battery. A 60 gallon tank holds twice the air as a 30 gallon.
Tank pressure is the voltage. A 150 psi tank holds more air then the same sized one at 100 psi.
The pump/motor is the charger. The more real HP, the faster the tank gets refilled.
Note that the hard equation is 1 HP = 750 watts assuming 100% efficiency on the motor. A lot of stores will advertise 'Peak HP' in excess of 5HP on a 120V compressor. Peak HP is mostly meaningless for a compressor. It doesn't really matter if the motor generates 6HP for that fraction of a second it is starting to spin up. What matters is the running HP. Be wary of any compressor claiming over 2HP on a 120V plug. 2HP = 1500 watts which is close to the max rating for most 120V outlets. Plus most motors are not 100% efficient.

CFM. Be sure to compare the CFM at the pressure your tool wants. Some low end compressors will list a decent CFM number at 40psi and a much smaller number at 90psi. Most tools want 90psi and most paint guns want 40psi.

A decent rule of thumb is 4CFM @ 100psi per HP. https://www.quincycompressor.com/air...r-horse-power/

Avoid the 'oil less' compressors. They tend to be under performing and overly noisy.

Thanks - yeah I was trying to see if I could get away with a compressor that puts out 6cfm on 110v. But thinking about it - I really dont need it right now as the only tool I have that really needs the CFM is the orbital sander - and I have a decent electric one also.

If it was my long term house - I would run a subpanel and the 220v ..... but just not worth it here.

So think I will give in and get me a 2.5cfm pancake for $120 to run plasma cutter and pump up tires so on ...... then when I get more permanent house in retirement then look to a full sized compressor.

Originally Posted by Rickysnickers

Also consider the tools you are going to use. A lot of them are rated at a certain cfm, or scfm at a specific pressure. Here's an example of an impact wrench, https://www.toolbarn.com/ingersollrand-231ha.html/ Notice the "average CFM at load." This is something else to consider when you purchase an air compressor.

thanks yes noticed that - appreciated.