Air compressor plumbing questions

[Csilko]

I recently bought the Northern Tool 60 gal/3.6 HP compressor and am trying to figure out the piping setup. I plan to do occasional blast cabinet work, air tools, and maybe some day dabble with auto paint, so I want to have an oiled and a dry drop. It seems there are multiple ways to pipe it. The NT diagram says to put a moisture trap as far away as possible from the tank as possible. The HF design doesn't have that. NT has 2 separate drops, HF has one drop with a sub drop on that line for oil and dry air. Both designs seem to make sense, but both are totally different.

Looking for an opinion as to which one is better and how long these runs should be. I purchased the 3/8" 100' PEX kit from RapidAir because it seems to get good reviews.

Also, this compressor came with a huge 3/4" outlet. Most lead hoses are 3/8", with 1/4" NPT threads. Same for the retractable air hose I bought from harbor freight. So, do I just put a 3/4 to 1/4 reducer on the output right away and keep all the piping and air hoses 3/8"??? Won't I lose flow or pressure? What is the purpose of the 3/4" main outlet on the compressor?

Thanks.

 

[bimmer1980]

Depends on how quick you want to get up and running..... Reducer fitting and directly thread on a moisture filter and regulator to an air hose....

Longer version -- get the 3/4 NPT to hydraulic hose fitting. Use hydraulic hose to another fitting and then into your pipe of choice - copper, aluminum, iron, etc.

I bought my hydraulic hose and fittings at tractor supply. I made a stainless steel mainfold of sorts using fittings from Supplyhouse.com or pexsupply.com. One of those two online stores....

I would use smaller regulators and oilers close to your point of use. No point in running oil through all of the lines and have potential contamination for paint or sandblasting.

Unless this is a commercial shop that will use air continuously, I would recommend not over thinking it. A couple of hose reels in key positions are very helpful tho.

 

[ZRX61]

Don't bother with an oiler, juts put a drop or two of MMO in the tool air inlet when you use them.

 

[Bucko]

Don't bother with an oiler, juts put a drop or two of MMO in the tool air inlet when you use them.

Good advice.
Many new air tools like nailers are oil-less and will not work too well if you oil them. I keep a few dropper oiler bottles where my different air tools are stored for quick use.

 

[The Cobbler]

I wouldn't use an oiler either. they are good in production shops where tools are used steady, and no one has to remember to oil them. a few drops now & then is best . the only way I would use an inline oiler would be if I had different couplers so you can't use an oiled line on a line that you don't want oil. ie spray gun . but that would be a pain in the **** in a home shop

 

[Zeke]

I'll chime in on the oiler — not for me. But I do keep one air hose only for painting hooked up to a filter/trap. I don't even want the compressor air coming directly into my guns.

AFA piping goes, sandblasting and painting are 2 out a few air hogs. A good way to help with that is to run oversized pipe as much as you can from station to station. You want the highest flow fittings everywhere you can put them for hogs.

Figure "E" doesn't show a moisture trap for the spray side. figure "B" is more in tune with how I'd do it.

 

[rayra]

If you want high flow to a blast cabinet you want to avoid necking down the tank outlet. Carry larger diameter plumbing to your cabinet fixture / connection. Or even a trunk run in the larger diameter and neck down sizes at the drops.
Putting the moisture trap far away is something to do with air cooling as pressure drops, giving moisture more time to condense out. IIRC. But that moisture is sitting in the bottom of the tank for the most part. It's a relative difference and you need someone citing real science and not decades of discussion lore to tell you if it really matters. If you are plumbing to a paint sprayer location, maybe put the moisture trap at that station.

/problem is there are too many folks parroting rigid adherence to miscommunicated ideas, compounded by lore and autism.

 

[Zeke]

....................................................... (snip)

/problem is there are too many folks parroting rigid adherence to miscommunicated ideas, compounded by lore and autism.

Pure ********. While some may just want to air their opinions, others have empirical experience. For instance, I paint cars occasionally and paint many other things as well. I lost count of how many spray guns I have of all kinds. 7 or 8 that use only compressed air as opposed to turbine generated or airless. That would bring the count to well over a baker's dozen.

Besides that, I have many air tools. Probably 20 or so. I have 5 compressors. None of that makes me any kind of expert but I'm entitled to an opinion, if from nothing else, over 60 years of using an air compressor. Now that goes quite away further back than the Internet so I guess I learned from employers, co workers, friends and literature.

I'm not alone. There are any here as old as I am, with more experience (regardless of age) and some professionals, e.g., engineers.

It's a consortium of thoughts. Some may be miscommunicated and some may be pastes from somewhere else. For the better part, there is decent advice in the majority. I don't know where the **** autism fits into this, but that's just a wrong thing to say.

 

[Csilko]

Wow, OK. So it looks like Northern Tool sells a RapidAir 3/4 NPT kit (didn't see much 3/4 stuff at tractor supply). So I would use a 3/4" NPT whip hose into the 3/4" Rapidair PEX piping, with roughly the depicted drain valves, main lines, and feeder lines depicted in diagram 1 above??? When I get to the distribution manifolds, it looks like they are 3/8 or 1/4 NPT. So my retractable hose is 3/8" with a 1/4" NPT male lead hose. Isn't this just going to have the same end effect as reducing the entire system down to 3/8 hose with 1/4" fittings at the beginning??? Guess I could run a dedicated separate station for the blast cabinet with 3/4" or 1/2" fittings and hoses???


I am asking because my $90 Rapidair 3/8" kit, along with about $20 of accessories would have piped that system. The 3/4" kit is much more, with fittings going for $20-$30 each, $50 for a lead hose, plus a new filter/moisture separator with 3/4" NPT. That brings my shopping cart to over $500 just for the larger PEX piping. Which incidentally is about what I paid for the entire compressor (it had cosmetic damage, so it was highly discounted). I hope the 3/4" setup is worth it.

Forgot to mention, this unit is only rated for about 12 CFM, so it is not the very large 2-stage compressors that Northern Tool sells. I know blasting and painting are air hogs, but as a DIY person I figured I would go slow and take breaks to let the compressor catch up anyway due to the low CFM. Will the 3/4 setup really make a difference compared to 3/8? Thanks.

RapidAir MaxLine 3/4in. 100ft. Master Kit Compressed Air Piping System, Model# M7500 | Northern Tool

The RapidAir 3/4in. MaxLine compressed air piping system is designed for high-demand air tool users and longer air line runs in large build...

www.northerntool.com

 

[Metal-Marc]

IB4 flex vs copper.

 

[Norcal]

As to a oiler in the line, do you want contaminated air lines? Too high a risk of getting oil on something you don't want oil on, just be religious about oiling any pneumatic tool that requires oil.

 

[yatg]

Forgot to mention, this unit is only rated for about 12 CFM

You could use the 1/2" maxline kit.
using their calculator

Flow Rate Calculator - RapidAir Products

Flow rate calculator contain system specific calculator, general calculator to calculate the products required for your air piping systems.

www.rapidairproducts.com

125psi, .50i.d., 100' = 23.70cfm

 

[Csilko]

As to a oiler in the line, do you want contaminated air lines? Too high a risk of getting oil on something you don't want oil on, just be religious about oiling any pneumatic tool that requires oil.

I was going to have a separate feed line for power tools with the oiler just before the outlet. But really, I am OK with just putting a few drops of oil in each tool before I use it. It's not like it is a pro shop with daily impact wrench use all day.

My bigger concerns were about the size of the piping and fittings. Also, is it really necessary to have that many drain lines and ball valves? I get the one before the system goes vertical, and also the one at the end of the main line. But do I really need another drain at the end of the feed line as well as a 4th drain at the extended feed line like in the first diagram above???

 

[Csilko]

You could use the 1/2" maxline kit.
using their calculator

Flow Rate Calculator - RapidAir Products

Flow rate calculator contain system specific calculator, general calculator to calculate the products required for your air piping systems.

www.rapidairproducts.com

125psi, .50i.d., 100' = 23.70cfm

OK, I think I might do that. In looking at the calculator, it seems I would be OK with the 1/2" rapidair regular (not maxline) system with the .375 ID piping. It says it should handle about 15 CFM. I am only going to have about 50' of line, and most of that will be to extend out for the drains, etc. like in the diagrams. The main drop (or two) will be toward the middle of my 36' long shop. So with a few 50' reels of hose I can easily reach every corner of the shop as well as drag the hose 20 feet outside if I were to attempt blasting out there or painting some outdoor furniture or something.

Thanks for the advice.

 

[redmondjp]

Another vote here for skipping the oiler. You will lose track of which air hoses are oiled and which aren't. And if you are using a blow gun (which is what I use my compressor for about 85% of the time), you don't want to contaminate things you are trying to clean or blow dry with an oil mist. The only place I would ever use an oiler is on an assembly line where you have dedicated lines to air tools.

 

[Csilko]

Sorry for the long delay, but I wanted to follow up on this post and the recommendations. I wound up finally getting this all set up last fall and forgot to post the pics. I used the 1/2 inch MaxLine Kit and had to order and exchange a bunch of valves and fittings online, so it took a while due to poor planning on my part.

I have the 3/4" whip hose going right into a basic filter right at the unit. Then the long downhill slope to the first air drain. Then the high downhill line that I tap 3 times from the top, just like the recommendations. The first tap is for blasting, so it goes through another filter and dessicant. The 2nd tap is for that 3/8" coiled hose for air tools, so it goes through a double regular filter. The last drop goes through the attic and pops out near the door, where I have a cheap 1/4" extra hose and metal roll wheel from harbor freight. This is for my "shop" air to clean stuff out.

I have the tool regular dropped down to about 90PSI for the tools, but I leave that last drop at full pressure to use for cleaning, etc. I also bought the separate drain valve extension from Amazon and have it going to a perforated gatorade bottle to drain the tank easily each day.
Overall I am very happy with the setup. The MaxLine stuff was very easy to set up, cut, and install. I did a few overnight tests and the system only lost 2 or 3 PSI overnight, so I call that a win (plus I drain the tank daily anyway). And of course, I decided to forgo the oiler based on the recommendations here. Much easier to just oil tools as needed.

Been using the air on lots of little projects - grinders, cutoff wheel, nailers, impact wrench for the truck, even and air saw, etc. Very happy. I am actually looking for more tools to add to the collection since it is kind of addictive getting new tools.

Thanks for the help and recommendations on here.

 

[Csilko]

Here is a pic of the tool holders I got from Amazon and a pic of the drain valve add on that I also got from Amazon. The last one is the cheap Harbor Freight reel and small hose for shop air.

I really like the tool holder - seems to be made of good metal and is made in the USA. I know people frown on Harbor Freight junk, and the central pneumatic die grinders are pretty junky, but I've been pretty impressed by the Chief line of air tools at HF. I have the die grinder, air hammer, air saw, and scaler so far. I have only tested the scaler, but the others seem pretty good. For a cutoff wheel, I just got a cheap one on Amazon that got great reviews. Overall I am happy with the setup.

 

[Mike65]

I have a 60 gal Craftsman compressor that I used a 3/4" ball valve for a shut off by the compressor then a 3/4" to 1/2" step down then a couple lengths of 1/2" steel pipe then a step down to 3/8" for the hose to the hose reel. The hose reel has a 50' hose on it so it will reach out into the driveway in front or on the side of the garage.

 

[nadogail]

The last two places I worked, had multiple large compressors. They fed a 2” pipe loop that encircled both plants. The compressor receivers were all fitted with electric spitter valves to keep condensate out of the system.
Our air drops were sized to the loads they fed. As I recall most of the work stations I plumbed in were fed by 1/2” copper lines I soldered with a propane torch.
Each machine operator was responsible to blow down their air supply.
Portable tools were used only by Maintenance Personnel, installed machines were fed by the cleanest air possible.

 

[RaisedByWolves]

Pure ********. While some may just want to air their opinions, others have empirical experience. For instance, I paint cars occasionally and paint many other things as well. I lost count of how many spray guns I have of all kinds. 7 or 8 that use only compressed air as opposed to turbine generated or airless. That would bring the count to well over a baker's dozen.

Besides that, I have many air tools. Probably 20 or so. I have 5 compressors. None of that makes me any kind of expert but I'm entitled to an opinion, if from nothing else, over 60 years of using an air compressor. Now that goes quite away further back than the Internet so I guess I learned from employers, co workers, friends and literature.

I'm not alone. There are any here as old as I am, with more experience (regardless of age) and some professionals, e.g., engineers.

It's a consortium of thoughts. Some may be miscommunicated and some may be pastes from somewhere else. For the better part, there is decent advice in the majority. I don't know where the **** autism fits into this, but that's just a wrong thing to say.

Easy pop pop. J/K<<<<just kidding.

The Autism quip is an internet thing that bled over from 4chan, if you don’t know of 4chan you’re better off not knowing.

I’ll agree with you on your thoughts and add that I made a custom dryer/condenser/compressor cyclonic type moisture catch/drain as I put my compressor in the attic.

It is wall mounted about chest height in the garage and catches all of the moisture from the compressor all the time and gives me nice clean dry air.

I used to have terrible air with lots of moisture and that solved the problem, but this is probably just more internet lore.

 

[RaisedByWolves]

As to a oiler in the line, do you want contaminated air lines? Too high a risk of getting oil on something you don't want oil on, just be religious about oiling any pneumatic tool that requires oil.

To add to this, I was taught to oil air tools BEFORE putting them away so as to prevent the innards from rusting in the event moisture gets trapped inside the tool.

All of the internals are lubricated via the incoming air or oil put directly into the fitting including the bearings.

Couple drops of oil, quick blip or two and it’s good for years in the drawer.

 

[Cobragr]

I used the RapidAir 3/4 x100ft system, very easy install and works well for me.

 

[jmountainjr]

A 3/4"NPT valve seems big for that size compressor? But I think the important pieces of plumbing up an air compressor system is adequate size of the main line piping and, as in both of your schematics, pulling the drops off the top of the main line. And you really can't have too many drains. I pull the drops off the top of the main and have a drain on the bottom of the drop. My shop was done long ago so the mains and drops are 1/2" black iron pipe.

 

[Wiz02]

Easy pop pop. J/K<<<<just kidding.

The Autism quip is an internet thing that bled over from 4chan, if you don’t know of 4chan you’re better off not knowing.

I’ll agree with you on your thoughts and add that I made a custom dryer/condenser/compressor cyclonic type moisture catch/drain as I put my compressor in the attic.

It is wall mounted about chest height in the garage and catches all of the moisture from the compressor all the time and gives me nice clean dry air.

I used to have terrible air with lots of moisture and that solved the problem, but this is probably just more internet lore.

@RaisedByWolves, I am interested in learning more about your "custom dryer/condenser/compressor cyclonic type moisture catch/drain" and l am sure that others do too. Do you have a write up or pictures?

 

[RaisedByWolves]

@RaisedByWolves, I am interested in learning more about your "custom dryer/condenser/compressor cyclonic type moisture catch/drain" and l am sure that others do too. Do you have a write up or pictures?

I wish I would have taken pictures during the build cause I **** at paint.

Ill probably resort to drawing's when I have some spare time at work and illustrate it the best I can.

The basis for it is the fact that I have my compressor in my attic and one component if it is everything flows down hill from the compressor. It would still work on a conventional system but it wouldn't automatically drain the compressor, but there is a workaround.

Ill get started on this this week.