Help me size my compressor needs

[NBN]

A few years ago I bought the shop where I was working when the owner decided he was ready to retire.
We were a small shop doing classic car restorations and had 3 guys performing the typical jobs found in this type of work. We had a paint booth, large blasting cabinet, and the typical air tools. I've got an 80 gallon Quincy with an extra 80 gallon tank for volume. The setup worked well and didn't seem to overwork the Quincy.

I'm now looking at downsizing the shop and relocating, becoming a one-man operation. I'll be loosing the booth and won't have the extra employees using air simultaneously, decreasing my air needs. Cars and parts will still be painted - on a smaller scale, the blaster will still be used as needed, etc.

As I'm planning on getting a new compressor, what's the thoughts on sizing my new purchase? Single 60? Single 80? I'm thinking the 80+80 as before will be a bit much.

 

[PCustoms]

Why not keep the existing compressor and ditch the second tank?

Selling it for pennies on the dollar to go buy a slightly smaller unit won't make sense IMHO

 

[NBN]

Why not keep the existing compressor and ditch the second tank?

Selling it for pennies on the dollar to go buy a slightly smaller unit won't make sense IMHO

I'm passing the Quincy onto a guy that helped me get things going.

 

[johninct]

80 gallon 2 stage.

 

[mikedodge]

How much blasting? Any 80 gallon should suit your needs.

 

[PoorUB]

5HP, two stage, 80 gallon. Tank size is somewhat irrelevant. 60 or 80 gallon is what you will typically find on a 5HP. A larger tank has the pump running fewer start/stop cycles, but long off time.

5HP is the minimum for sand blasting. Most air tools can use a bit smaller compressor. I went from a 3HP to 5HP. The 3HP was a bit short, the 5HP unit keeps up with my demands easily.

 

[firebirdparts]

I think technically you do need a 5 hp 80 gallon (like say 15 CFM). For all of us one-man-shops, there's a possibility you buy a $500 compressor and just deal with it. There used to be a big jump in price from 11 SCFM (like say 3 ish hp) up to whatever is the next size up. that is a little less of a gap today.

I know $500 compressors don't cost $500 anymore but you get the idea. You technically need a 5 hp but you can do whatever you want to do by using a 3hp and smoking cigarettes once in a while.

Oil free produces a lot less air per hp FWIW. And also a lot noisier.

 

[TJay]

As previously stated, almost any 2-stage 80 Gallon should fit your needs perfectly.

Since I work with IR compressors, my choice would be the 2340N5-V.

 

[BillK]

Single 80 2 stage should be all you need. I have a 45 year old Curtis 5 hp here at my business and it does all that you are talking about just fine.

 

[pcmeiners]

As I'm planning on getting a new compressor, what's the thoughts on sizing my new purchase? Single 60? Single 80? I'm thinking the 80+80 as before will be a bit much

Tank size is not the issue, cubic foot per minute is. It will be a foolish move to dump the Quincy if it puts out approximately 17 cfm or more (5 hp or more) which is minimum for blasting.... very foolish.

 

[FTG-05]

"Hey guys, I need an air compressor. I only need it to fill bike tires once a month!"

GJ recommendation:

 

[PCustoms]

"Hey guys, I need an air compressor. I only need it to fill bike tires once a month!"

GJ recommendation:

Except the guy is painting cars and using a sandblaster....

 

[BillK]

Except the guy is painting cars and using a sandblaster....

I have painted 2 cars with my 50 year old 2 HP 20 gal Craftsman It is Identical to the one in this thread:

resto-mod vintage Sears air compressor

resto-mod vintage Sears air compressor Decided to restore/modify/upgrade my old Sears air compressor. model: 106.153783 20 gallon tank meets ASME code twin cylinder - VT series pump with long life needle bearings 2-horsepower 230V - requires 15-amp service capacity per sticker on unit......=...

www.garagejournal.com

I have even done some blasting with it but only small stuff outside at home. If I was doing a lot of blasting I certainly would want something larger.

 

[FTG-05]

Except the guy is painting cars and using a sandblaster....

Nothing - nothing - goes over your head; your reflexes are so fast, you would catch it!

 

[Chris_Hamilton]

Honestly IMO as I do the same type of work as you do, you don't really want to go any smaller than what you have now or did have. 25 CFM is what I consider the minimum especially if you plan to blast.

 

[PoorUB]

Honestly IMO as I do the same type of work as you do, you don't really want to go any smaller than what you have now or did have. 25 CFM is what I consider the minimum especially if you plan to blast.

Some of you guys are a bit nuts! I have sandblasted a lot of stuff with a 3 HP compressor. It was almost adequate for a hobby situation. 5HP and 15 CFM would be fine for most of us. I can understand if you are running a large shop and doing a ton off sand blasting that way more is better, but in the OP's situation I would recommend 5 HP, or 7.5 HP compressor at the most. I knew a guy that did sand blasting and he had set up as a stationary unit a 100HP diesel engine powered compressor, but he sand blasted pretty much 10 hours a day. He hired a couple "kids" to prep items and move things around while he was blasting.

 

[Imatk]

I have a 60-gallon Quincy QT-54. I've not painted an entire car so I can't comment on that. I have painted sections of a car without issue.

I have a blasting cabinet and it has been USED extensively.

I've never once had a hiccup blasting. No issues with air, I have a three filter setup for moisture and long runs of copper pipe... it has worked flawlessly.

I couldn't physically fit an 80 gal in my setup and was worried that 60 wouldn't be enough. It's been more than enough... for me.

 

[PoorUB]

I have a 60-gallon Quincy QT-54. I've not painted an entire car so I can't comment on that. I have painted sections of a car without issue.

Sand blasting takes a ton more air that a paint gun. I have painted cars with 3 HP and it didn't run constantly.

 

[Metal-Marc]

Go big.

 

[Chris_Hamilton]

Some of you guys are a bit nuts! I have sandblasted a lot of stuff with a 3 HP compressor. It was almost adequate for a hobby situation. 5HP and 15 CFM would be fine for most of us. I can understand if you are running a large shop and doing a ton off sand blasting that way more is better, but in the OP's situation I would recommend 5 HP, or 7.5 HP compressor at the most. I knew a guy that did sand blasting and he had set up as a stationary unit a 100HP diesel engine powered compressor, but he sand blasted pretty much 10 hours a day. He hired a couple "kids" to prep items and move things around while he was blasting.

I can only comment on my experiences. I have an ALC 110 lb pressure blaster and when I'm media blasting a body or frame it runs 80% or more of the time. I have a 7.5 HP 25 CFM Champion. Im just a one man Shop abd i consider it the minimum really. Hardly nuts.

When you refer to manufacturers literature about CFM requirements with the ALC it's up to 35 CFM consumption with the biggest nozzle.

5hp and 15 CFM would be OK for most spray guns but marginal for alot of other common tools in a bodyshop. DA's and big air powered 8" rotary sanders to name a couple. Bigger is always better. It will make less water, won't run as often, less stress on the machine etc.