How to match compressor with tools?

[rick carpenter]

Is there a rule of thumb for a minimum compressor capacity/size over tool requirement? Not continuous-use tools like sanders etc but say a nailer that requires 4.1 scfm. I asked here a while back about a pawn shop special I was looking at but I didn't get it. I was just assuming it would be enough. Probably not the way to do it tho...

 

[redmondjp]

I'm not sure exactly what you are asking here. A nailer will never get close to needing 4.1scfm unless you are using it machine-gun-style. The smallest compressor will operate an air nailer just fine. That's one really nice thing about nailers - you can get away with a very small, lightweight compressor when using them.

For continuous-use high-flow tools such as sanders, grinders, cut-off wheels, etc you will want the largest compressor you can afford. Something with at least 12-15scfm @90psi. Sand blasting cabinets often will use even more than this.

Now you can get away with using a smaller compressor with a die grinder or other high-cfm tool, if you are willing to accept the fact that the compressor will be running continuously, you will have to stop and let the compressor catch up (esp. if it's a light-duty one as it will overheat if run continuously), and you will get a lot of moisture out of the tool's exhaust.

My '5HP' (actually about 3HP) 60-gallon single-stage compressor will not even run one high-cfm air tool very successfully - the pressure will drop to about 85psi and it will run continuously. This despite the fact that the compressor claims it will deliver 11scfm at 90psi and the tool claims it only needs 4scfm. You know that both numbers are lies (they use tank volume to lie on the compressor side, and very inefficient air motor uses far more air than claimed on the tool side).

Does this help any?

 

[kctyphoon]

IMO - you can pretty much use any compressor with an air tank for a nail gun as they dont use much air to begin with - if i were shopping id say a 6 gallon at a min, but you can use brad nailers and such even with a 1 gallon and 3, it will just run more.. the 6 gallon pancake style is pretty much the statndard i would say for nail guns - assuming your not a professional roofer or thinking of anything out of the norm other than household projects..

 

[rick carpenter]

Thanks. I've got a 2.1@90 Ridgid 2-gallon compressor for trim guns. My CH framing gun says it needs 4.1@90 for 16 per minute so I'm wondering how to figure the minimum capacity/size baseline for a bigger compressor to buy. I've always relied on others in the crews to supply the right size compressor & guns.

I'm not a pro -- obviously -- but I do a bit of demo/rehab/rebuild after disasters and now I want to use the CH gun with a compressor of my own.

 

[machine_punk]

I just used a large framing nailer to build a fence, and my 30-gallon/120 volt/ 15 amp compressor didn't even breath hard (went a LONG time between refilling).

With finish nailers and staplers, you'd be OK with whatever little 'pancake' compressor they sell at the big box stores.

I run a die grinder on my compressor and it gets to where it runs continuously and still falls a little behind...and, starts squirting water out of the tool after a few minutes.

Kev

 

[kctyphoon]

I would just use what you have.. worst case, if you find the thing is constantly running trying to keep up with demand, then you can look for something a little bigger. but honestly i think youll be fine, especially with ocassional use.

 

[Domus]

When I worked on air compressors (many moons ago) our rule of thumb was 1HP = 4 CFM.
So a compressor with a 5 HP electric motor would power a 20 CFM compressor.

 

[thewatusi]

Thanks. I've got a 2.1@90 Ridgid 2-gallon compressor for trim guns. My CH framing gun says it needs 4.1@90 for 16 per minute so I'm wondering how to figure the minimum capacity/size baseline for a bigger compressor to buy. I've always relied on others in the crews to supply the right size compressor & guns.

I'm not a pro -- obviously -- but I do a bit of demo/rehab/rebuild after disasters and now I want to use the CH gun with a compressor of my own.

Unless you're a professional framer or roofer I doubt you'll come anywhere close to this frequency.

 

[rick carpenter]

.... My CH framing gun says it needs 4.1@90 for 16 per minute so I'm wondering how to figure the minimum capacity/size baseline for a bigger compressor to buy....

Unless you're a professional framer or roofer I doubt you'll come anywhere close to this frequency.

Oh yeah I knew that, you can barely force me up on a roof and I gotta think too much between trigger pulls anyhow! I only wanted to buy one big enough to adequately power my framer (and therefore the lesser scfm guns I have too), but not too big for ease of transportation issues. Like people have said here, I'll just see how my current compressor does with it. If it doesn't work well enough, I do have my eye on an oiled HF 8-gal 4.0@90 compressor.

Thanks y'all!