I'm thinking 3/4 PEX and a RapidAir kit for about $200 that has 100' of line and enough components for 3 drops. Compressor is a big ol' Quincy belt drive, 12 CFM @ 125 PSI

Questions:

1. Do I really need 3/4 or will 1/2 do? 1/2 is cheaper but I wonder if it will move enough air for a small blast cabinet and occasional use of air impacts and ratchets.

2. Kit, individual components or a combination? I'd like to add a ball valve at the compressor and make provisions for a drain leg at the compressor as the first run will be about 6 feet vertically to get out of the compressor room.

3. Is there an affordable (sub $100) air drier that actually works?

4. Where should the air dryer go in the system - Right at the compressor or just before the drops?

5. Regular PEX or the PEX-AL-PEX stuff? (125 PSI Max)

Everything I've read says a huge NO to using PVC, not sure if the same concerns apply to PEX.

Some discussion a few months ago:

https://sigforum.com/eve/forum...470086084#7470086084

I went with the RapidAir 1/2" kit and added to it where I needed drops and such..all from Amazon.

I run a 5hp 80gal Champion and large blasting cabinet and have NEVER had delivery issues. Even going through my 3/4 drying/cooling labyrinth.

For drying, I made my own 3/4" copper cooling/drying with multiple drops to drain water. Google it as there are many options for making your own. If you buy one, its supposed to go right after the compressor.

At each drop I have a 1/2" separator and a coalescing filter..then regulator.

https://www.tptools.com/1and2-...ter,74.html?b=d*8081

https://www.tptools.com/1and2-...r,8785.html?b=d*8081

Im running a 10 x 20 shop, powder coating.

NO PVC...nono

quote:

Originally posted by P250UA5:
Everything I've read says a huge NO to using PVC, not sure if the same concerns apply to PEX.

This is very true for a couple of reasons.

1. When it bursts, it creates shrapnel.
2. Oil degrades the PVC, as does UV.

AFAIK, PEX, especially the aluminum lined sort, does not have these issues.

Pex pressure ratings

200°F at 80 psi
180°F at 100 psi
74°F at 160 psi

pex gets more brittle over time.

Lots of lawsuits.

I just use a spool like ensigmatic did.
I had it leak once, and it was a 10 min replacement.

If I was going to bury lines behind anything I would use black pipe.

I didn't know you could use any type of plastic. News to me. The last time I plumbed the inside of one of my shops I did it in black iron using a chop saw and one of those hand ratcheting threaders with a 3/4 die.

I would use copper or steel pipe. Personally I like copper. It is easy to work with and cools the air quickly.

You want to have a gradual down slope of all lines, then a water separator at the end of where the line must rise vertically.
When using a blast cabinet, drying out the air is a big help. So have a water separator at that location.

This message has been edited. Last edited by: c1steve,

http://www.sharpe1.com/sharpe/...ge/air+piping+layout This is a good setup we used.

 
Black pipe does the best job of acting as a heat sink and condensing out water from the compressed air. On long runs from the compressor, incline the line down to allow the condensed water to fall away from the compressor. Use risers at every manifold to allow the water to fall down before entering the manifold, and have a drain leg at each drop to catch the water. Also, a drain leg right at the compressor is a good idea, prior to the line running up.
 
From experience (of doing it over), make good use of unions to join sections of your run. Plan where you might need to remove a section, for example to replace a regulator that goes bad.
 
A short flexible line is a good idea between the compressor and the fixed lines.
 
I used this diagram from TPTools as a guide to piping my system. You need to click the link to download the pdf diagram.

I would go copper

avoid plastic at all costs

We ran PEX. +1 for a flexible junction between machinery and the hard lines.

We use auto drain valves, which also work well.

We have a freezer dryer, but it wasn't cheap - nec. in our case.

After perusing Ewe Toob and other sources and checking my junk pile spare inventory, I decided to go with this for an air dryer.

I'll also put particulate filters and water traps (or desiccant) at the drop for the blasting cabinet and one for spray painting.

The pic is blurry…do you have isolation valves on those drops?

Otherwise, the air will short circuit your cooling channel risers.

quote:

Originally posted by Patriot:
The pic is blurry…do you have isolation valves on those drops?

Otherwise, the air will short circuit your cooling channel risers.

Oops. Hadn't thought of that. I'll fix that, thanks!

quote:

Originally posted by PHPaul:

quote:

Originally posted by Patriot:
The pic is blurry…do you have isolation valves on those drops?

Otherwise, the air will short circuit your cooling channel risers.

Oops. Hadn't thought of that. I'll fix that, thanks!

Make sure to add about 4-6” of tube before the valve for water to collect. Otherwise it will lay in you bottom of you riser tubes and get entrained back into air flow.

Hopefully there's enough room for water to collect. In any event, it'll get drained daily.

Also, there'll be a 6-ish foot vertical run from the compressor connection up the opposite wall and across the ceiling before it gets to the dryer. The compressor connection will have a drain leg as well. That'll all be black iron pipe. The compressor will be connected to the riser via a braided flexible connection to dampen any vibration.

Very nice…that will be fine I think…

I have my set up in a controlled environment and was very surprised at the amount of water.

I also added a mechanical auto drain on my compressor.

Champion has a std kit but the company sells it under the name tsunami auto drain. Not as noisy as a tune based unit and works only when the compressor is being used.