Air compressor questions.

[JMortensen]

I just got this compressor home today: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93274

 

I honestly don't know jack about regulators, but this compressor did not come with one. So, in keeping with my HF gift cards deal, I can choose from the following:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=1118

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=45009

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92261

This one looks like it goes directly on an HVLP gun:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90590

 

The first one looks the most familiar to me because my welder regulator has a similar knob on it (which isn't saying much), but honestly I can't tell the difference between it and the other two and I'm a bit confused about what exactly they do.

 

I would imagine that there is a screen filter in the bottom of the canister on any of these that separates the water from the air as it passes through. Some of them say they "lubricate" tools.

 

Does one add lube to the regulator and then distribute it through the system?

 

Sending lube through the air lines seems like a good way to screw up a paint job. I bought my new compressor with the intention of painting my Z, so I want to make sure that I do what I need to do to get a good paint job out of it.

 

Is the fact that the first one can go up to 160 lbs and the others only to 125 of any consequence?

 

Seems like most air tools are rated for 90, and an HVLP gun should be rated for like 40, so why would you need 160, let alone 125.

 

Is there a difference between the one canister style and the two canister style?

 

Is it necessary to use the regulator on an HVLP gun if you have a regulator at the compressor? Why couldn't you just turn the main regulator to 40 lbs?

 

I think this may be more for a shop type setting where one guy needs 40 lbs and another needs 90 and so on, but for the garage I think the main regulator would be sufficient. Still want to know that I have that right...

 

Of the choices above, does anyone have a preference? Are they all junk? Is there something better I should buy instead?

[Tony D]

Does one add lube to the regulator and then distribute it through the system?

 

Is the fact that the first one can go up to 160 lbs and the others only to 125 of any consequence?

 

Is there a difference between the one canister style and the two canister style?

 

Is it necessary to use the regulator on an HVLP gun if you have a regulator at the compressor? Why couldn't you just turn the main regulator to 40 lbs?

 

Of the choices above, does anyone have a preference? Are they all junk? Is there something better I should buy instead?

 

1) Correct, adding lube to the lines is bad. Most shops have a 'Dry Line' and a 'Lubed Line'---even going so far as to use different color hoses for each. I have YELLOW hoses I use on Oiled lines (get it, yellow for the color of oil?) and BLUE lines that are NOT TO BE USED WITH OIL (get it, blue for pure air?)

IMO, you are best plumbing your whole system as "Dry" and adding FRL (Filter/Regulator/Lubricators) at points where you will add the hose for the tool. I have set up people's home systems with large Q-D's on the tank, and then hook up either a Lube setup when they are using tools, or a non lube setup with a dryer and filter when they are painting. Definately do something to keep oil out of your air lines that you will be painting with.

 

2) Not really, but the ability of the regulator to flow what you need is more important. I usually set up the regulator at the tank out of the side fitting with a regulator that is 3/4" in pipe size, from this I usually put a coalescing filter to knock out any moisture that may migrate out of the tank, to a series of valved "T's" in manifold form from the Stainless Steel Section at Home Depot. You regulate down at the tank to 120 or even 100psi, and the standard 125psi fittings are fine to use---do not use BIP, Carbon Steel, or anything that corrodes! From the "T's Manifold" since each take off is valved, you can hook up smaller, point of use regulators to drop the line pressure to your gun or tool as needed. The key is to keep the high pressure air in the tank where you can easily control leaks. After that point, using properly sized air lines you can easily run 100 psi out to them and have sufficient flow to drive most anything. And anything that does leak is leaking at a reduced pressure, minimizing losses.

 

3) I'll come back to this one in an edit. The single cannsiter unit is simply a filter/dryer cartridge---I would use this on the PAINTING lines. I have that exact same filter regulator unit and have had it since 1985 - 86 when I originally started painting my Z overseas. This is a unit to use on the YELLOW lines. The 'two cannister' units are FRL's (Filter, Regulator, Lubricator) and would b e used when you are running air tools. The 1/2" size Orange unit would be the one I'd buy, and then bush down for whatever pipe or hose size Q-D you decide on using. The reason being is the lubricator bowl is bigger, and the bigger it is, the more oil you have to go through before refilling it. Also, since the filter is larger in surface area, it will go longer picking up swarf from your system without getting clogged. Additionally, a larger filter housing (oversized in relation to actual flow) will actually slow down the air quite abit, and allow more moisture to coalesce out and be trapped by the filter element. Kaeser uses this fact to their advantage by selling people oil flooded screw units fitted with humongous filters that need changing every five years---but the surface velocity across the media is so low that there is minimal pressure drop and filtration efficiency is sky high wen dealing with oils and aerosols to drop out---they market it as an 'oil free package'. Just because they have a lubricator on it doesn't mean you need to install it! I have just used the filter and regulator section---it's not like they are expensive, so letting them sit till you need them elsewhere in the system is not a biggie. The last regulator is trash, and simply a restriction in the line, it only regulates when the line is flowing---and is a stopgap against not properly regulating the flexible line pressure at point of hookup to the distribution system. People do this all the time, run a higher line pressure becuase they are using components that are too small to begin with! Size stuff correctly and you will never need one of those.

 

4) As I said above, you could do that, but then you are going back to the big regulator and constantly adjusting it for the tools you have with different pressures. If you have a Big Reg to drop it from storage pressure to close to maximum point of use pressure (say 100psi) then each of your manifolded lines could be set to different pressures. 45 for the HVLP on a Blue Hose to your gun, and 90 through an FRL on a Yellow Line to your air ratchet or impact. The key thing to remember with regulation is to regulate as close to point of use as possible---that way the high pressure air is there in the line for flow demands on startup.

 

5) I'll come back to this one in an edit as well, but generally the smaller point of use regulators are throwaway, so those I get anywhere. For the large one on the tank, as well as it's filter/coalescer I go with a brand name like Arrow Pneumatics, Ingersoll-Rand, Dominick-Hunter, Harrison, etc etc etc... you can ee above the only one I wouldn't use is the last one---properly regulate and use the correct size lines (3/8" minimum for most everything to minimize frictional losses) and there will be no need for that last abortion! I have the Brown Regulator on my wife's "Tire Compressor" which she also uses for the staple guns nail guns, and blowing up of balloons for the kiddies when they come over. The Orange one I use off my Devilbiss simply because it was easier to get than the Arrow Pneumatic one I wanted but was out of stock at the time... Laziness plays into many of my decisions, you see.

 

What you may seriously want to consider is the refrigerated air dryer they sell, if you will be doing a lot of painting and are in a humid location (it never rains in Seattle, does it? LOL) the amount of moisture it will knock out will greatly help with paint quality. It will also decrease the moisture you get from your ratchets and impact guns when using them for extended periods (die grinder also comes to mind) Nice not to have wetness blowing all over the work... It will effectively give you a 35 degree dewpoint, so as long as you are working in 50-60 degree weather you should never have an issue with water in your air lines. But that may take some more setup on your part---generally when someone buys a dryer, I tell them to find an old compressor tank and run some air through the dryer, to the second tank (wet receiver and dry receiver)---this way you can blow off things like the floor with the wet tank, and use the dried air for tools and etc. Dry air makes for happy tools! And better paint jobs.

 

Gee, you would think I work with compressors or something, huh? Have I talked to you about plumbing your garage with copepr hard piping and multiple hose barbs with quick disconnects? (Tim Allen Voice) Arr Arrr Arrrr!

[JMortensen]

I was hoping you'd jump on this thread Tony! Thanks. You wrote quite the novel there, so let me just restate in the simplest terms to make sure I understand completely.

 

1. I can go with just one regulator since I don't mind going back and adjusting the regulator between jobs. Pretty much everything I use takes 90 lbs, except for the spray guns I have yet to buy, and I won't be painting very much at all.

 

2. I could (but don't have to) install a manifold off the tank so that I could have a "dry" line without and a "wet" line with lubricant. The double reservoir is the lubricant adding type, and that would be the type to buy for the wet line.

 

3. The single reservoir unit is the type I'd want for painting because it does not add lube to the lines. I'm thinking I could use this and then just periodically lube my tools. I've been using a crappy oilless compressor for the last 7 or 8 years and just lubing the tools, so I really don't see this as too much of a hassle.

 

As to the copper line thing, the original owner of the house built this garage to paint cars. He's got flourescent lights in the walls and has the shop plumbed with copper lines already. The problem is he appears to have moved his compressor around a couple times, and there are several lines that stick out of the wall in various locations that don't have any caps on them and it's hard to tell which lines go with which system, or if it is all one big system that just has several loose ends that need to be tied up. Basically there's a whole bunch of plumbing in the garage and unfortunately a lot of it is behind the drywall. I was thinking of possibly doing the plumbing all over again and leaving it exposed. I dont mind the look of the copper pipe and then at least I'd know what I have and where it goes to.

 

I did work at a business in CA where they plumbed the walls with PVC pipe. The instructions that came with my compressor even say that this is a bad idea, but they had it like that for years and never had a problem, and one guy did the whole shop in one day, just using that purple plumber's glue like you use on sprinkler systems... any thoughts on that?

[johnc]

I don't run any oil/lube through my air lines. I just have a little bottle of air tool oil and I put a couple drops in the tool the first time I use it each day.

[Pop N Wood]

Don't use PVC for compressed air. It is brittle and will shatter if struck with something. The broken shards will explode and don't show up on xrays. They make land mines out of PVC. Go to the OSHA site for more information. I think it is even illegal now.

 

If you start putting compressed air into one of the open copper pipes i am sure you will quickly figure out which ones are hooked up and which ones aren't.