Air tools/compressor questions...

[oz in SC]

Posted this over on Shop talk but the more the merrier...

We are thinking of buying an air compressor and assorted tools for building 'stuff'..

So we are looking for some advice on the various compressor sizes,oil free or not,how big for around the homestead projects etc...

What y'alls opinion???

[travlnusa]

The tools you want to run will decide what compressor you will want to buy. If you are just looking to run nail guns, just about any compressor will work. If you want to run sanders, grinders, cut-off tools, etc, you will need a bigger unit as they need a large steady air supply. There are forumlas (spelling, sorry) you can use to decide exactly what you want, but buy as much as you can afford.

I have about a 3 hp/26 gal tank, oil-less motor. While it works for me, I would like to have a larger one as I have to wait for the compresser to catch up with high volume tools.

Air compressors makes LOTS of water. You will want to drain you tank time to time, based on how much you use it, so your tank does not rust from the inside out.

With that much water, you need to oil each tool before and after each use. That, along with keeping your output PSI around 90, will give you long tool life.

If you are thinking about getting a large vertical tank unit, there are compaines that will design your air line system for you at no charge, showing were you need line drops and water traps.

If you are adding air lines, I advise you do NOT use PVC pipe. Others might chime in here saying it will work, and they are right, until it blows out and that in not pretty or safe with pvc. Use black pipe.

[Darren]

The oil free compressors are not usually used for powering air tools. Those are normally used for specialty stuff like removing greenware from plaster molds, some types of painting and medical uses.

[travlnusa]

Darren makes a good point.

When I said oil-less, I was referring to a motor that is sealed, that you do not check or change the oil. Usually found on lower cost units.

True oilless units are as he stated.

[Mary in Minnesota]

We have a Thomas Renegade model T-200ST and love it. It is perma-lubed, so there's no adding oil. It holds 4 gallons of air and can provide 4.6 CFM at 90 PSI. It is about the queitest compressor we could find. It's fairly light weight for moving around a house putting up trim, etc. I think we paid about $350 for it.

[farminghandyman]

IN my opinion there are Two basic types industrial and cheap,

It is not that the cheap ones are bad or wrong, but they are cheaply made, most are for occasional use or portability, like in the little pancake ones for air nailer's,

even many of the upright compressors are little different than the small roll around units,

the industrial are the 2 stage 175 psi case iron oil bath heads, and usually have true 3 to 15 hp motors,

most of the small roll around units have very inflated Horse power ratings, 745 watts = one horsepower,

and usually the cubit foot a min are strong or rated at a low psi rating

it is like we have an old 1/2 hp air compressor my dad bought 35 years ago, and it still goes but it starts to pump up fairly fast and then it hits about 40 psi and it starts to slow in its filling and by 80 it is talking a long time, and it is close to 20 Min's to fill to 100 psi,

what I am trying to say, is the cfm at 40 psi is much greater than the CFM at 80 or 90psi,

if you need working pressures above 90 you better look in to a 2 stage unit, most single cylinders are not designed to pump above 100 psi,

air tools take a lot of HP to do what a fairly small electric tool will do,

I have a true 3 hp on one compressor and it will not keep up with with a auto body sander if used continuously,

but a little 1/6 hp de-walt sander will run for for hr, continuously,

impact wrenches are great, air ratchets,

air drills (i think electric is better), the same with sanders,
die grinders there ok but takes a lot of air, the dremal type tool is just as good,

tire filling , air wrenches, air nailer's, blow guns, air clamps (depending on use), the air shears are usually cheap but work if you don't use on materials thicker than stated,
I use a air buffer on the tire machine, and the tire machine is air powered, blowing dry wall texture good,

I was just trying to think of the air tools I have or used,

impacts wrenches or ratchets, 1/4", 3/8", 1/2", 3/4", 1". for most things I like air better than electric,
tire machine, good
air tire buffer,good
die grinder, good,
drill 1/2" and 3/8" and 1/4" I would not buy again unless there is a special need,
DA air sanders 3 different types, (like the electric better for most things)
4 air nailer's and staplers, great tools
air nibbler and shear, (replaced with a electric kett unit)
paint sprayer (for automotive type work very good, house no good unless you have paint pot and internal mix nozzle (good air less better)
blow guns use a lot, good
tire filling a lot. excellent.
air clamps, GOod, really good if using a foot valve and for hands free operation,
I am sure there is more but to tired to think right now, hope this helps,

what ever you do get one that has more CFM than you think you need, you wont be sorry,

[oz in SC]

What about these compressors?:
http://www.harborfreight.com/cpi/cta...emnumber=47065

http://www.harborfreight.com/cpi/cta...emnumber=90385

We would mainly be using it to build 'stuff',doubtful we would use it for bodywork.

Might have a few mechanics air tools but not even sure then.If we do it would be an 3/8'' air ratchet,1/2'' impact and maybe a die grinder.

We just spent the last two weekends doing home handyman projects and hammering nails while lying in the dirt under the house was quite UNfun....

[farminghandyman]

I don't like direct drve units for the speed they run, but they are probly ok,

[patarini]

sears has some nice ones -- mine is still running strong after 8 or 9 years now i guess
http://www.sears.com/sr/javasr/searc...et=Subcategory

[farminghandyman]

sorry got cut short on the last post,

it will probably do what you want to do, with it, but I think I would want to step up to a unit that at lest Carry's a US brand even if it is an import, (my guess the quality would be better than a harbor freight unit), over the years I have bought a number of items from harbor freight, some are good and some are junk, but you all ready know it is low cost,
so the quality is probably not as great as a better know brand,

I own a direct drive portable unit and use it in the wood shop it is a good unit, but I have also repaired them for others, (not easy to get parts for a national know brand) my guess is if the harbor freight unit would need parts in a year or two, you would have to replacing the entire unit,

but then again it may last you for 20 years and need to trash it because the tank rotted out do to moisture,

and I really don't have a recommendation's on small or large units, (my ,main shop unit is a shop built unit using a good quality pump, motor and tanks, and is pushing 25 years old, and the tanks need replacing, and would like to get a two stage pump), the wood shop one is a Coleman direct drive oil less unit (the camping gear company) and is now about 7 years old, the first year it was job site unit and ran nail guns, for house building, actually I am impressed with its quality, noisy as all get out tho, IT uses a teflon ring for a seal to my knowledge all the oil less do,

I personally think there are better units out there for about the same moneys, but I may be wrong,

my SIL has a de-walt and porter-cable pancake units both were used and still going strong, he bought them for about $50 each from a guy going out of business, and run nail guns fine, still noisy, most all the direct drive are noted for there noise.