An alternative air compressor set up

[jimhaebe]

Good evening to all. First time posting, long time observer. I am finishing off the inside of my newly constructed pole barn shop. I am a hobbyist, but I like having industrial strength equipment, well built equipment, plenty of capacity etc.
In the past I have had 3 phase equipment. I no longer have any 3 phase stuff and do not want to have to have a phase converter just for my aircompressor.
I have had my eye on a used 10 horse unit, but it is 3 phase. Initially I considered getting the phase converter, but it was $1400 bucks, almost as expensive as the compressor.
Then I thought how about (2) 5 hp. units in series? Now I am thinking of 1 larger 7.5 hp(still single phase) and just a 60 or 80 gal. receiver tank. I have a large blast cabinet and am planning on doing some pressure pot work also. Any thoughts, am I approximating the larger compressor? Also, this alternative aircompressor setup will be cheaper than the big 10 hp. unit. Thanks....Jim

 

[AMCguy]

Re: An

Have you thought about an engine powered compressor?

Or, how about an engine modified to be half engine, half compressor.

I'm getting ready to build a slant six that is half and half. It should put out about 50 cfm @ 150 psi running at a fast idle.

Welcome aboard.

 

[RECox286]

I have a monoblock tow behind that uses a ford 302. A monoblock

uses 4 cylinders to pump air, and 4 cylinders for power. It delivers

roughly 110 cfm @ 105 psi. The company went belly up, but the

machine continues to work as advertised. Oh, it has a Zenith

1 bbl carb. Worst part is the fanbelt won't stay tight b/c one of

the pulleys is not running true, or has a pinched spot that I can't

seem to find. One of these days I'll get it fixed...

Uncle Bob

 

[Torque1st]

Run the two 5HP units in parallel.

 

[jimhaebe]

Thanks for everyone's replies. What effect does running the 2 compressors in parallel have have on available air?

 

[1948]

60 or 80 gal. receiver tank? hah youre kidding right? dude you need at LEAST a 150 gallon tank if youre gonna do anything serious. if you get a bigger tank your motor wont be running every few seconds. get yourself a 200 gallon with a standard motor.

 

[theoldwizard1]

Thanks for everyone's replies. What effect does running the 2 compressors in parallel have have on available air?

You add the volume (CFM) of both compressors.

You have very high requirements if you are going to eed anything bigger than a 5hp 80 gal tank ! A Quincy single stage will deliver 16 CFM @ 90psi, max 140psi.

If that is not enough, a Quincy 2 stage with give you 17.7 CFM @ 90 psi, and a whopping 17.2 CFM @ 175 psi !

With a 7.5 hp motor jump that to 23.8 and 22.6 CFM. That is like 4 or 5 1/2" impact guns running at the same time !

 

[1948]

most air tools arent the issue, but to use air sanders or air grinders or spray guns thats the problem, or esp sand blasters.

 

[brownbagg]

i made one out of a vw motor once, two cly to run the motor, two to pump air

 

[Oldmics]

I dont know what your starting with but Marathon motor company offers a single phase 10 HP motor.

I have a 5 HP setup and finally cooked the motor after 7 years of abuse.

I am upgrading to the 10 HP motor with the existing 5HP compressor.This 10 HP motor requires a compleat upgrade back to the fusebox.

The compressor folks tell me that I will get 7 1/2 HP functionality from this setup.Once the compressor takes a **** I will replace it with a 10 HP compressor.

I"m planning on bigger blasting chores with a pot with this new setup.Guess we will se how that works out.

Oldmics

 

[amolaver]

i'm in a similar spot. i was originally looking at 7.5hp, then a 10hp, and now i'm back to two 5hp machines, each with an 80 gallon tank (this is all single phase). 90% of my air work would be quite happily supplied by a single 5hp machine. but when the blaster is in use, its just not enough. 30+CFM is what is needed to work with any real duty cycle.

so i'm planning on buying two 5hp/80gal units, and plumbing them in parallel with shutoff valves so i can use just one of them most of the time.

ahm