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Cantedvalve

Home Shop Air System upgrades - help

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It's time I start getting the shop air system order.  We have a compressor already, and its worked well for us.  16CFM @ 90PSI, 80 gallon tank, 5HP.  What I don't have a good grasp on is what I need to be able to shoot my own paint (HVLP I would assume).  We don't have much in the way of plumbing on this thing so far - some black pipe, a small water separator, and that is it.  Hoses are 3/8" stuff we picked up at a Ford dealer auction many many moons ago.  Not much has been spent on this system so far.  What I have in mind is:

  • running about 40 feet of 3/4" copper tubing in a zig zag pattern right next to the tank to "simulate" the long run of pipe needed to cool the air and condense the water to extract it
  • 2 stage oil/water separator coming off the copper monster
  • ..................

And that is all the farther I have gotten.  As far as hoses or fitting sizes I want to run a paint gun (or air tools), I havent the slightest idea what I want or need.  I know bigger is better, but when is better enough?  My gut says that for most of my tools, a quality 3/8" hose with high flow (1/4" flow size) fittings on each end is sufficient (don't have any problem running tools now).  However, this same system is going to be running paint guns in the near future (albeit with different hoses, and probably additional drying and filtering equipment).  Do I want or need 1/2" hose?  3/8" flow size fittings?  Should I get a secondary tank to put somewhere near where I am spraying?

So yeah... not sure where to go from here.

 

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1 hour ago, Cantedvalve said:

It's time I start getting the shop air system order.  We have a compressor already, and its worked well for us.  16CFM @ 90PSI, 80 gallon tank, 5HP.  What I don't have a good grasp on is what I need to be able to shoot my own paint (HVLP I would assume).  We don't have much in the way of plumbing on this thing so far - some black pipe, a small water separator, and that is it.  Hoses are 3/8" stuff we picked up at a Ford dealer auction many many moons ago.  Not much has been spent on this system so far.  What I have in mind is:

  • running about 40 feet of 3/4" copper tubing in a zig zag pattern right next to the tank to "simulate" the long run of pipe needed to cool the air and condense the water to extract it
  • 2 stage oil/water separator coming off the copper monster
  • ..................

And that is all the farther I have gotten.  As far as hoses or fitting sizes I want to run a paint gun (or air tools), I havent the slightest idea what I want or need.  I know bigger is better, but when is better enough?  My gut says that for most of my tools, a quality 3/8" hose with high flow (1/4" flow size) fittings on each end is sufficient (don't have any problem running tools now).  However, this same system is going to be running paint guns in the near future (albeit with different hoses, and probably additional drying and filtering equipment).  Do I want or need 1/2" hose?  3/8" flow size fittings?  Should I get a secondary tank to put somewhere near where I am spraying?

So yeah... not sure where to go from here.

 

I have seen where people have used the long run of copper pipe zig-zagged up and down vertically with a short ~10" length of pipe with a ball valve at the bottom of each "Loop" to drain the moisture that accumulates as the air cools down. The one person I talked with claimed that it worked pretty well...

This website offers a commercially available solution using aluminum pipe and compression fittings and claims to be good up to 232 PSI... and it's only $276.49    https://www.compressorpros.com/qlk32-air-cooling-piping-system-1-2/

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On the Mustang Steve site, Steve posted somewhere (maybeTech or Tips & Tricks) a neat way to cool the compressed air. Get a 5 gal plastic bucket with a roll of copper wire. Both ends come thru a drilled hole and connect to your air line. Add ice to the bucket. BAM!

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That's an old

1 hour ago, RPM said:

On the Mustang Steve site, Steve posted somewhere (maybeTech or Tips & Tricks) a neat way to cool the compressed air. Get a 5 gal plastic bucket with a roll of copper wire. Both ends come thru a drilled hole and connect to your air line. Add ice to the bucket. BAM!

That's an old home brewing trick - I would have never thought of it for air. We use them to rapidly cool the wort (unfermented beer) after boiling it. Called wort chillers...

 

wortchiller.jpg

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2 hours ago, mwye0627 said:

I have seen where people have used the long run of copper pipe zig-zagged up and down vertically with a short ~10" length of pipe with a ball valve at the bottom of each "Loop" to drain the moisture that accumulates as the air cools down. The one person I talked with claimed that it worked pretty well...

This website offers a commercially available solution using aluminum pipe and compression fittings and claims to be good up to 232 PSI... and it's only $276.49    https://www.compressorpros.com/qlk32-air-cooling-piping-system-1-2/

Here is my crude drawing... my plan was to zig zag horizontally, with a little slope on each leg so the water could move top to bottom...image.thumb.jpg.35977981cc3dff1a9db5ec64cf67ea71.jpg

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1 hour ago, RPM said:

On the Mustang Steve site, Steve posted somewhere (maybeTech or Tips & Tricks) a neat way to cool the compressed air. Get a 5 gal plastic bucket with a roll of copper wire. Both ends come thru a drilled hole and connect to your air line. Add ice to the bucket. BAM!

I’ve heard of that before too. Wouldn’t even need ice... water would do.  But ice would be better.  Pressure concerns me.  I tend to overengineer things so I never have to worry about a failure. .  I’ll look into the coiled copper... might be a cheaper solution than my zig zag of copper pipe.  I am pretty keen on ditching the black pipe though.

How do you get the water out of the coils?  No drain I assume...

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Okay, so I am reading about an aftercooler for the compressor. Basically, cooling and drying the air before it goes into the tank.   Not as an only solution, but an additional solution. Takes some fabrication, but might be worth it. Seen setups using AC condensers and ATF coolers.  I might look into it. 

What size NPT do I want to use for the hardware connections?  At least 1/2... what about 3/4?  Where do I see diminished returns?

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On Friday, January 11, 2019 at 5:23 AM, Cantedvalve said:

Okay, so I am reading about an aftercooler for the compressor. Basically, cooling and drying the air before it goes into the tank.   Not as an only solution, but an additional solution. Takes some fabrication, but might be worth it. Seen setups using AC condensers and ATF coolers.  I might look into it. 

What size NPT do I want to use for the hardware connections?  At least 1/2... what about 3/4?  Where do I see diminished returns?

This is what i am going to do for my compressor

 

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That's a lot of valves.  I may do something similar, but different... but not first.

FIRST, I am putting an aftercooler and an auto drain filter on it.  I plan to use a transmission cooler as the condenser... mount it on the fan cage in front of the compressor pulley, which is also the fan for the compressor.  That is step 1.  I have the parts ordered, they should be here Monday... or was it Tuesday.  No matter.

Also have to replace the drain valve on the compressor.  The wings came loose and now I cant open it.

 

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Okay, after letting this one simmer for a week (almost), I am satisfied with adding an aftercooler to the compressor.  If I can figure out how to mount a fan on it, I will do that too if the temps dont come down enough to remove the moisture.  Most of the setups I have seen dont run a fan, but instead rely on the compressor pulley/fan thingy to pull air through.  I will have the air coming from the cooler go through a filter to capture whatever it can before it goes into the tank.

I am switching out the black pipe for copper.  Copper is cleaner.  I have a flexible line from the tank to the plumbing to isolate vibration.  I probably should get vibration pads for the compressor, but that can be done later.  I will have a hookup right outside the compressor, and another after the pipe goes through the wall. 

I don't plan on another filter until I get the line through the wall into the other side of the shop (we have a big side, where the compressor is, and a small side... both have lifts and need air for tools and such).  It will travel another 30ish feet before the next filter, which will be the last inline part (probably a 2 stage with a regulator).  Ill have 2 outlets here... one on each side of the wall (so back through the wall) after the filter and regulator.  I will have more filters and such for painting that wont be hard plumbed... but that is for a later time.

I am contemplating running the copper pipe UP the wall at the compressor, but there are two obstacles.  1) there is electrical conduit that runs the length of the wall, and b) I hate heights.  so probably just take it through the wall there.

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I haven't heard of air cooler like this before, but I assume this is better for shooting paint/HVLP or something, most tools don't seem to care.  It would seem to me that the copper coil is a better option in either case - even if you didn't put it in a bath, if would work as well as copper on the wall I think.  Seems like a T joint near the bottom with some kind of  collector with a drain valve as seen on most compressor systems should work.  The rigid copper on the wall seems like a rather expensive option with lots of labor for all those sweated on elbows and joints...  

Please keep us posted on what you do - this is an interesting build. 

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21 hours ago, Cantedvalve said:

Okay, after letting this one simmer for a week (almost), I am satisfied with adding an aftercooler to the compressor. 

I went through this last summer before I painted one of my cars. Was going to use a home AC evoparator as aftercooler. One tip; add a second check valve (the valve you have at the entrance to the tank) to the entrance of your aftercooler. That way when the compressor stops (when the pressure reaches to set point) the air in the aftercooler won't be released making a looong hissing sound.

I have not installed the after cooler though, just made a Z shape using copper pipe (about 40 feet total pipe), air from comp goes in at the top and the lines are inclined down so the water flows down. Then attached the water separator/regulator to that. Drained the water from the tank and water separator before paint, added the disposable filter (bought from paint supply store) to the gun and painted the car. Did not have any water problems in paint on a humid September day in GA (besides the humidity leaking from the mask and my sweat running down like a stream). I don't think I will add the aftercooler; I believe the Z cooler is effective for a hobbyist unless you are a body shop painting all day long.

 

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Okay, I have a decision to make.  I have the piping sizes and layout done.  Now I need to decide what to use.  I have been pricing out copper, as it is readily available and recommended as a clean solution.  My total spend is coming up to $135 with all tubing, flux, solder, joints, etc. for 40 feet of 3/4" copper and 4 attachment points.  All in all, good setup at a minimal cost... assuming I can solder it (I assume I can). 

Now the other day I came across Rapid Air Maxline kits... 100' of 3/4" tubing and a variety of parts to do 3 outlets.  More tubing, less attachment points, $139.  To get the 4th attachment (and go through the wall like I planned), I would need 5 more right angle fittings, another outlet kit... damn that's like another $130 right there.  To save what... soldering?

You know what, I think I just answered my own question.

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35 minutes ago, Cantedvalve said:

Now the other day I came across Rapid Air Maxline kits... 100' of 3/4" tubing and a variety of parts to do 3 outlets.  

I used a kit like that (don't remember the brand). Later on it started slow leaks at some of the connections. Now I have to turn the valve at the exit of the tank if I am not using air otherwise the compressor keeps coming on because of the slow leaks.

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Yeah, and I read that the kit I considered can have leaks too.  So copper it is.  I have everything on order, and it’s about $140 with tax.

I also got a 50 foot 3/8” Flexzilla hose and some 1/4” V-style high flow fittings and couplers.  When I get to paint, I’m gonna get 1/2” hose and 3/8” fittings.

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Okay, so I need a pressure regulator.  My compressor likes to run up to 135 PSI.  My tools dont need more than 100 PSI.  So the answer is a regulator.  Now there are regulators, and then there are HIGH FLOW regulators.  The one I am looking at has a standard flow of 210 CFM, while the high flow is 300 CFM.  Given that my compressor does 16.8 CFM at 90 PSI, I am thinking the standard will work just fine.  Now, what will the CFM be down at paint gun range of 30-40 PSI?  I have no idea, but I bet it will be less than the 16.8 CFM the compressor can do at 90 PSI (which should be higher at a lower pressure).  So let's say its 100 CFM... the 210 CFM more than doubles that.

Am I wrong to assume that the "high flow" are for compressors that put out at lot more CFM than what I have or will use?

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Hold the phone... so what kind of fittings have I read everywhere NOT to use on a compressor?  Compression fittings.  What do I find when I take off the hard line from the pump to the tank? Compression fittings!

one of them was weird too... loose sleeves have bevels on both sides... this one had bevel on one side.

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So worked on the compressor lines yesterday. Pulled all the black pipe. Wow. It was yucky in there. 19 years of rust and junk. Never again!

Started sweating together the copper. Got the tank outlet done. Put on the soft line (to isolate plumbing from the compressor), measured, and built the shutoff valve and filter circuit. I’ll get a picture or two.

Our original filter is a nice Speedaire/Parker unit that needs some love. Manual drain is plastic and years of using pliers in it has worn it out. Ordering a new auto drain and new 40 micron element. 

I have a really old (yet unused) Reelcraft 5000 series hose reel with 50 foot of hose. Used to work for them 19 years ago, so that is how old the reel is. I’ll install that into this new circuit as well.

Making some progress!

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