What size compressor ?

[michael-fisch]

So, unless you have an unlimited source of LP air, and, don't have to pay for the electricity used to make it, a masterline electric booster for around 8.5k is the cheaper solution for HP O2.
Eventually as my supply of 300bar O2 gets used up, I'll have to bite the bullet since there is no way in hell I'll burn $5 of electricity an hour to compress drive air which then goes through a booster to pump O2 to a higher pressure.

Life in europe was so much simplier, with a ready supply of 300Bar O2 tanks at every AirLiquid, MesserGriesheim, Linde, or Westfahlen gas supplier.

Michael

 

[tbone1004]

So, unless you have an unlimited source of LP air, and, don't have to pay for the electricity used to make it, a masterline electric booster for around 8.5k is the cheaper solution for HP O2.
Eventually as my supply of 300bar O2 gets used up, I'll have to bite the bullet since there is no way in hell I'll burn $5 of electricity an hour to compress drive air which then goes through a booster to pump O2 to a higher pressure.

Life in europe was so much simplier, with a ready supply of 300Bar O2 tanks at every AirLiquid, MesserGriesheim, Linde, or Westfahlen gas supplier.

Michael

welcome to the land of cheap electricity...
Average rate where I am is $0.08/kwh which IIRC is about 1/4 of the cost of what you're used to in Germany, and ours is weirdly cheap, and I think national average is around $0.12, so still about a third of what you're used to.

My compressor is 1kw while running give or take and is 3cfm at 90psi. AG30 is about $6k with a good compressor and filtration system, the Masterline is about $9k. It'll take a LONG time for the electricity costs to outrun the cost of the Masterline. The Masterline is certainly more efficient, and much faster, but you have to pump a metric****ton of O2 before they come anywhere close to evening out. I'm not going to do the math, because it's in the tens of thousands of cubic feet. Is the Masterline better? Obviously, but you don't buy one of those because it has a reasonable ROI. If our power cost 3x what it does now, you may be able to make an argument for it, but not with our cheap power here.

 

[michael-fisch]

Hey, I'm looking foward to finally living in Florida, but I'll miss readily available cheap 300 Bar O2.
Cheaper He, gasoline and electricity will go a long way towards making me feel better, but I'm terrified of the help my cat is going to offer untill the contents of the house and garage are arranged to his satisfaction. Since I would never dream of killing my cat, I'll have to kill myself - but that wouldn't work either since he hasn't yet learned to use a canopener.

Michael

 

[tbone1004]

Hey, I'm looking foward to finally living in Florida, but I'll miss readily available cheap 300 Bar O2.
Cheaper He, gasoline and electricity will go a long way towards making me feel better, but I'm terrified of the help my cat is going to offer untill the contents of the house and garage are arranged to his satisfaction. Since I would never dream of killing my cat, I'll have to kill myself - but that wouldn't work either since he hasn't yet learned to use a canopener.

Michael

I filled up at $1.24/gallon the other day. That's about .32 Euro/Liter

 

[michael-fisch]

I filled up at $1.24/gallon the other day. That's about .32 Euro/Liter

Tbone1004,I hate you!
I'm still paying around $100 to fill the 18 gallon tank on my Opel.
I remember the days 20+ years ago when I filled up my rental for the 4th or 5 th time in Mayo and heard the gas station owner telling his son " He's the guy who pays cash, instead of trading watermelon for gas like everyone else."
Michael

 

[BRT]

@a878bob remember that that is cycling once per second as that is the rate they are designed for. Also, the point of me pointing you to those is to show that it's basically impossible to have a big enough compressor at home.
The AG30 is capable of consuming something stupid like 70cfm, which would require a ~15-20hp compressor, which is about 15kw and would require 70a service, just for the compressor. You're not going to have that at your house. It will just run slow.

@BRT low pressure air compressors rule of thumb is 4:1 for cfm:hp. the 1:1 ratio is generally applicable for high pressure pumps, but the drive gas compressors are all around 4:1.

My rule of thumb used to be 1.4 or so. After reading your message I went and looked and indeed, it seems like you are correct. I'm confident nothing I've ever owned will do 4-1 and they didn't use to have ratings that high. Something has changed.

Edit. They have gone from rating them in CFM to SCFM. I see a half inch drive CP air impact gun now uses 25 scfm

 

[tbone1004]

My rule of thumb used to be 1.4 or so. After reading your message I went and looked and indeed, it seems like you are correct. I'm confident nothing I've ever owned will do 4-1 and they didn't use to have ratings that high. Something has changed.

it may be 3:1 for some designs, but that holds true for our 40yr old behemoth compressors at work as well as the california air tools at home