Air Compressor System

WA7OPY

Precision Fit
Aug 1, 2019
902
Missoula, mt
First Name
Phil
Willys Model
  1. Jeepster
Willys Year:
  1. 1947
The older tanks lasted longer, I think core 10 was used for the steel shell and ends but you need to look inside for rust pits, hydro test and ultrasound to know for sure...Phil
 

dld

Bigger Hammer
Dec 4, 2020
78
Bozeman Montana
First Name
David
Willys Model
  1. Other
Willys Year:
  1. 1947
As I said before, I have the HF floor standing cabinet and hooked it up to my Craftsman 2hp, 150psi, 33 gal and it sucks. First the cabinet sucks. Side entry is a problem changing the plastic shield, rubber gloves, etc. plus it leaks media everywhere. Through all the seam corners, the door when you open it, etc. Always a mess around the floor. Basically a POS Chinese made junk. And the compressor can’t keep up. So, this next time I want to do it right. I see the Eastwood floor model has a top load which will make changing shield and gloves easier plus i think will be better loading and no media drips when you open the door. It says needs 7 cfm at 90 psi.

I will also want to have an air run going from the garage to the wife's craft-room and my craft closet, both in the house for things like air brushing and general blowing. I'm guessing 50 foot horizontal run, plus drops. What size should I run? Since it will not be accessible once everything is buttoned up, I won't have access to repair, replace, etc.

Per the air to the hobby room, you should be fine with 1/2" ID, whether it is pipe or hose.

It has been said here that PEX is okay for compressed air, my research suggests differently. There are poly tubes that are rated for air and I've used a ton of them with push-to-connect fittings, but generally only up to 1/2" OD. I know they make them in 16mm (~5/8") OD, but I would always use braided hose if it got that big.

A nice, easy line sizing calculator is available from Gates. It is a hose calculator, so it is probably making some assumptions that aren't completely valid for a pipe system, and it definitely doesn't take into account fittings, but it is likely close enough for most applications. https://www.gates.com/us/en/knowledge-center/calculators/air-flow-calculator.html

If you really want an accurate number, you would need to look up the Cv for every fitting in the line, know air conditions, etc.. I would use the Gates calculator and size it so I have an acceptable pressure drop, knowing that the actual drop might be double what the calculator shows.
 

mrholmquist

Sharpest Tool
Jun 5, 2014
457
oshawa
First Name
mike
Willys Model
  1. Pickup
Willys Year:
  1. 1957
I would be interested in you research regarding pex. My understanding is that pex is not rated for compressed air . Having said that many hobby guys are using it and have been using it for years in their home shops . Every single time the subject comes up on any automotive forum it sparks the great pex debate . I have read on many different forums a huge number of guys use and have been for years without issue. I have not seen one person report a problem . Most seem to be running 140 psi in the line or less. So you have two sides.. Guys for only seem to have for their argument "i've been using it for years" . Guys against only seem to say " it's not approved for compressed air" . No one seems able to submit any details .
 
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Ira

Bigger Hammer
Sep 26, 2020
122
Los Angeles
First Name
Ira
Willys Model
  1. Pickup
Willys Year:
  1. 1960
The potential with plastic is what happens if it get's hit and splits. PVC turns into a a lot of shrapnel, no idea about PEX.

Ira
 

Ira

Bigger Hammer
Sep 26, 2020
122
Los Angeles
First Name
Ira
Willys Model
  1. Pickup
Willys Year:
  1. 1960
Just pointing out the potential downsides of unknown plastic. Like I said, I've no idea about PEX. it might be perfectly safe. It seems to be a similar material to the stuff I use for small air lines on my industrial robot.

Ira
 

dld

Bigger Hammer
Dec 4, 2020
78
Bozeman Montana
First Name
David
Willys Model
  1. Other
Willys Year:
  1. 1947
I would be interested in you research regarding pex. My understanding is that pex is not rated for compressed air . Having said that many hobby guys are using it and have been using it for years in their home shops . Every single time the subject comes up on any automotive forum it sparks the great pex debate . I have read on many different forums a huge number of guys use and have been for years without issue. I have not seen one person report a problem . Most seem to be running 140 psi in the line or less. So you have two sides.. Guys for only seem to have for their argument "i've been using it for years" . Guys against only seem to say " it's not approved for compressed air" . No one seems able to submit any details .

Let me kinda backtrack and say that my research suggests that PEX isn't rated for compressed air.

PEX all seems to be made for plumbing applications of mostly potable water. When something is rated for pneumatic systems, there seems to be a level of chemical resistance that is inherent in that rating, along with UV rating. Anything rated for compressed air will have the assumption of having some oil in the system, whether it is from a compressor head, a filter-regulator-lubricator combo, or in the case of flexible tubing/hose, from the environment (i.e. shop floor spills).

So, it may be that it is simply the fact that the vast majority of pneumatic systems are surface mount where there will be UV light.

But...it may be that PEX can be softened and compromised by petroleum products. It might be a fatigue issue in the fittings, or something my pea brain can't imagine right now.

The fact that it is not rated for pneumatic systems makes it difficult/impossible to figure out what the failure mode might be.

That said, PEX is a soft plastic compared to PVC, and is likely less likely to produce shrapnel.

I'll be completely honest here: I might use PEX in my own application, where I control the variables and who is around it. I would never install PEX for someone else, or recommend they do so.

I also want to say that my pneumatics experience/understanding, and bias are based on a decade of designing, installing, and supporting pneumatic systems on custom multi-million dollar machines.
 

timd32

Sharpest Tool
All-Star
Jan 4, 2020
396
NJ
First Name
Tim
Willys Model
  1. Pickup
Willys Year:
  1. 1950
One big Crate ✔.

Blast cabinet arrived today.

Pipe says arriving maybe Friday, but the connectors said Monday.

Putting the new (well new to us its a 2014) fork lift to work.

Saves a few bucks on the lift gate fee. I still need to get it to my home shop. Deal with that later.

20210407_154512.jpg
 

mrholmquist

Sharpest Tool
Jun 5, 2014
457
oshawa
First Name
mike
Willys Model
  1. Pickup
Willys Year:
  1. 1957
Let me kinda backtrack and say that my research suggests that PEX isn't rated for compressed air.

PEX all seems to be made for plumbing applications of mostly potable water. When something is rated for pneumatic systems, there seems to be a level of chemical resistance that is inherent in that rating, along with UV rating. Anything rated for compressed air will have the assumption of having some oil in the system, whether it is from a compressor head, a filter-regulator-lubricator combo, or in the case of flexible tubing/hose, from the environment (i.e. shop floor spills).

So, it may be that it is simply the fact that the vast majority of pneumatic systems are surface mount where there will be UV light.

But...it may be that PEX can be softened and compromised by petroleum products. It might be a fatigue issue in the fittings, or something my pea brain can't imagine right now.

The fact that it is not rated for pneumatic systems makes it difficult/impossible to figure out what the failure mode might be.

That said, PEX is a soft plastic compared to PVC, and is likely less likely to produce shrapnel.

I'll be completely honest here: I might use PEX in my own application, where I control the variables and who is around it. I would never install PEX for someone else, or recommend they do so.

I also want to say that my pneumatics experience/understanding, and bias are based on a decade of designing, installing, and supporting pneumatic systems on custom multi-million dollar machines.
So I actually have it in my shop. 9 years ago we rented an area and since it was a rental i did not want to spend more than i had to on the air system. As i said read a lot of comments on various groups but no one really provided any research or hard facts. I figured i would give it a try in spite of that. The stuff is stupid cheap . Think i bought a 100 foot roll of it for 18 dollars. Easy to work with fittings can be purchased literally anywhere. Started with a 40 foot run and a drop at three places in the hobby shop.As the years went we added to it as needed . Very easy to change and re work as u go. And did i mention cheap. So here i am with a shop full of pex and not one issue in those years. We turnoff the compressor when we are done and when we return often several days later the tank is still full of air. Still i was interested in any research a or actual knowledge anyone had. . Clearly this could only fly in a home shop . I work as a certified auto and truck mechanic and our shop is all black iron pipe
 
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cactuspete2u

Sharpest Tool
All-Star
Nov 4, 2010
367
colo
First Name
scott
Willys Model
  1. Wagon
Willys Year:
  1. 1954
So I actually have it in my shop. 9 years ago we rented an area and since it was a rental i did not want to spend more than i had to on the air system. As i said read a lot of comments on various groups but no one really provided any research or hard facts. I figured i would give it a try in spite of that. The stuff is stupid cheap . Think i bought a 100 foot roll of it for 18 dollars. Easy to work with fittings can be purchased literally anywhere. Started with a 40 foot run and a drop at three places in the hobby shop.As the years went we added to it as needed . Very easy to change and re work as u go. And did i mention cheap. So here i am with a shop full of pex and not one issue in those years. We turnoff the compressor when we are done and when we return often several days later the tank is still full of air. Still i was interested in any research a or actual knowledge anyone had. . Clearly this could only fly in a home shop . I work as a certified auto and truck mechanic and our shop is all black iron pipe
I have been very interested in this thread. My question (if you don't mind) is, how did you stabilize the ends where you plug into? After reading your post I'm contemplating doing this for the ease and I am on a very tight budget. Thanks.
 

mrholmquist

Sharpest Tool
Jun 5, 2014
457
oshawa
First Name
mike
Willys Model
  1. Pickup
Willys Year:
  1. 1957
I have been very interested in this thread. My question (if you don't mind) is, how did you stabilize the ends where you plug into? After reading your post I'm contemplating doing this for the ease and I am on a very tight budget. Thanks.
This is the fitting that the standard shower head in your bathtub is attached to. Attach this to the wall and screw your airline coupler
to it The large hole is a standard pipe thread.
 

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cactuspete2u

Sharpest Tool
All-Star
Nov 4, 2010
367
colo
First Name
scott
Willys Model
  1. Wagon
Willys Year:
  1. 1954
This is the fitting that the standard shower head in your bathtub is attached to. Attach this to the wall and screw your airline coupler
to it The large hole is a standard pipe thread.
Thanks, for the the life of me I just couldn't get a picture in my head.
 

timd32

Sharpest Tool
All-Star
Jan 4, 2020
396
NJ
First Name
Tim
Willys Model
  1. Pickup
Willys Year:
  1. 1950
Thanks, for the the life of me I just couldn't get a picture in my head.
I might actually have 2 of those. Will look and see, I bought brand new ones but took the guts out and just replaced those parts. Still in the box, will dig them out and take a pic if they work. Your welcome to them.

Edit......... nope they are 4 way and some sort of diverter valves.

I had 3 of them, no wonder I only changed the valve parts. Was upgrading the other parts and these came in the kit.

IMG_20210407_213210.jpg
 
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Ira

Bigger Hammer
Sep 26, 2020
122
Los Angeles
First Name
Ira
Willys Model
  1. Pickup
Willys Year:
  1. 1960
I like keeping the disconnects facing down so the hose hangs straight. Might have issues with dirt getting in the hose but I'm guessing the air will move it along no matter what.

Ira
 

mrholmquist

Sharpest Tool
Jun 5, 2014
457
oshawa
First Name
mike
Willys Model
  1. Pickup
Willys Year:
  1. 1957
Originally i thought about drip pockets below each drop with drains for moisture but did not do it in the end . That is what they do at work . They have two 100 hp ingersol screw compressors on the roof. As i mentioned i have 2 60 gal single stage compressors sistered which gives me 120 gal storage at around 135 psi. The benefit of an 80 gal two stage unit would be to cram more air into the 80 gal tank as the pump is capable of 175 psi. Then you would regulate the air exiting the tank to 120-130 before it connects to your lines. As i mentioned i bought the two 60 gal compressors for considerably less than i would have paid for 1 80 gal 2 stage. I am not sure what the difference would be in cubic feet of air that i can store in my two 60s as compared to a single 80. I assume it would be somewhat similar due to the 80 running the higher pressure.I mostly only run the first compressor and the second tank acts as a air volume storage and a large water separator. If i turn both compressors on they are rated at about 11 cfm each for a total of 22 cfm at 90 psi. The 80 gal dual stage i was looking at at the time was rated at 18.5 cfm at 90 psi. I do a fair amount of painting and have had zero issues with moisture using this setup. I have a small water separater on the line i paint with and it is always clean and dry when i am done. The pex lines make for an excepionally clean delivery system .
 
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mrholmquist

Sharpest Tool
Jun 5, 2014
457
oshawa
First Name
mike
Willys Model
  1. Pickup
Willys Year:
  1. 1957
I like keeping the disconnects facing down so the hose hangs straight. Might have issues with dirt getting in the hose but I'm guessing the air will move it along no matter what.

Ira
In that case you could just mount the fitting i pictured to the roof and run a suitable length of drop hose depending on your ceiling height and a coupler on the end of that
 

cactuspete2u

Sharpest Tool
All-Star
Nov 4, 2010
367
colo
First Name
scott
Willys Model
  1. Wagon
Willys Year:
  1. 1954
I might actually have 2 of those. Will look and see, I bought brand new ones but took the guts out and just replaced those parts. Still in the box, will dig them out and take a pic if they work. Your welcome to them.

Edit......... nope they are 4 way and some sort of diverter valves.

I had 3 of them, no wonder I only changed the valve parts. Was upgrading the other parts and these came in the kit.

View attachment 96505
Thanks for the thought.
 

timd32

Sharpest Tool
All-Star
Jan 4, 2020
396
NJ
First Name
Tim
Willys Model
  1. Pickup
Willys Year:
  1. 1950
Pipe has arrived. Little bit of damage to the cardboard tube but inside all was well.

It's a pretty long shipment, the 7'6" are probably a better idea. It will add some unions if going that route.

The 8/2 wire was not stock at Lowes on Friday (web inventory was off a bit) and I ran out of time looking for it. Was going to order online should have at this point. It was a few dollars compared to Lowes.

IMG_20210412_162359.jpg

Moving along.
 

Ira

Bigger Hammer
Sep 26, 2020
122
Los Angeles
First Name
Ira
Willys Model
  1. Pickup
Willys Year:
  1. 1960
I've been pretty happy with getting wire from: Wire

Just make sure to check with shipping. I was buying some bigger gauges and this seemed like the best deal I could find.

Ira
 
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