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VaccaRabite
So I went to Home Depot today, armed with some scratch and the will to buy an air compressor and a DA air sander.

HD sells the husky line. So, I went to the tools, found a DA sander (Husky, needed 4cfm @ 90psi, and the box said it would work continously with 20+ gallon compressors).

Then I walked over to look at compressors. They had a Husky 24 gallon compressor that flowed 5.1 cfm @ 90 pis on sale ($225). Score! but then, on top of the motor, was a little chart with reccomended tools and non-reccomneded tools. All sanders and DA sanders were non-reccomneded.

I called over a HD floor guy, who called over another 2 guys, and we could not see a good reason for the prohibition. But, we decided that if the factory did not reccomend it, then it should not be used as such, and I walked over to the electric tool section and bought an electric DA sander. sad.gif

I am going to need to buy a compressor by the spring. I'm clearly in the "hobbiest" catagory, and may not use the tool again for a long time aftyer I am done with my 914, but when it comes time to paint, it will probably be cheaper for me to buy one then rent one - given the slow nature that I work. I want to know why the sander was not reccomended, when the compressor could flow the air and had a big enough tank according to the tool. I have theories, but I thought somone here might be able to give better advice.

Thanks

Zach
Joe Bob
DAs take a LOT of air....I have the big MOFO......100 gallon tank, 220v and the DA still can get ahead of it.....
Twystd1
Good DAs use a bunch of air..

Kinda like cutting the end off of the air hose.... Lotsa air.

What kind of electrical do you have going into your work area?????

That will dictate how big of a motor you can purchase.

So whatcha got as far as electrical???

220? What gauge of wire?

110?

Or are you willing to run an extra circuit for this?

Clayton
PRS914-6
The problem with a $225.00 compressor is you get what you pay for. It's "non industrial" so you can't run it all day every day.....A big tank only gets you a reserve. If you run a sander a lot and suck the tank down, the compressor will run and run and they are just not designed to take it. For impacts ratchets, no problem, they don't draw much. A small job using a sander would be OK just not big multiple projects.

Personally, I use a 5 hp 220V industrial model with a large tank but I have a bead blaster and other high demand air tools.
Dr Evil
Dude, just get one for less $$$ at Harbor Freight, they would never put a warning about what you cant use wink.gif poke.gif
VaccaRabite
I am limited power wise. I only have 110 going to the garage (which is detached), running a 220 circut there (I'd love to do it) would require trenching under my driveway.

Anything that I buy won't be used all day everyday. After the 914 is done, the next task would be running a floor nailer as I continue to lay new flooring down in the house. Mayhaps I'll go check out HF tomorrow and see what they are offering.

I like having the week off. i need to do this more often. :-)

Zach
Joe Bob
QUOTE(Vacca Rabite @ Dec 26 2006, 06:14 PM) *

I am limited power wise. I only have 110 going to the garage (which is detached), running a 220 circut there (I'd love to do it) would require trenching under my driveway.

Anything that I buy won't be used all day everyday. After the 914 is done, the next task would be running a floor nailer as I continue to lay new flooring down in the house. Mayhaps I'll go check out HF tomorrow and see what they are offering.

I like having the week off. i need to do this more often. :-)

Zach


And that's a problem? confused24.gif

REAL men have 220...how else can you run the manly man kegerator?
Twystd1
Check to see what gauge wire you have coming into the garage.

Sometimes you ge tlucky and the PO had 10 gauge wire run.

Ya never know until ya look...

Do you have only 1 SINGLE breaker going to the garage?

Can you pull the MAIN PANEL breaker cover off and see if the same piece of conduit has an extra wire in it you can use for 220?

It's worth a look... Unless you are sure of what you have.

C
Joe Bob
You can also she if you can fish bigger gauge thru the existing conduit....
Brew
I smoked my Sears 5hp 22gal 6cfm @90 compressor DAing a car the first time I tried it. They just wont keep up with continous use on alot of high cfm air tools (DA, air grinders, etc.). Bigger is always better! And, bonus, if you can get 220 to the garage, you can plug in a real welder. welder.gif

That being said, the rebuilt Sears unit is still the only one I have, and it can get most jobs around the house done!
Twystd1
In the last month...

I have aquired 2 commercial compressors for a couple of friends to use in their commercial Harley shops..
One 80 gal. and one 100 gal.

Both were under 350 bucks used. I wired em up for nada...

They paid more for the water trap filters and the oil trap filters than they paid for the compresors. (400 bucks)

Oil and water traps are very necessary if you are ever guna shoot paint.

It also helps the tools last longer.
(read no water in lines to create corrosion)

I'm not trying to complicate this.... I just wanna help ya spend your money... (put smiley here)

Z was right about the conduit. Might be able to pull a 220 circuit through your existing conduit. Maybe even a sub panel. then you can do whgatever ya want. welder, compressor, etc....

If'n ya live close... I can come over and run it for ya. Used to have a electrical and GC contractors license.
(they gave me one??? idiots...)

Lemme know...

Clayton
computers4kids
QUOTE(mikez @ Dec 26 2006, 05:07 PM) *

DAs take a LOT of air....I have the big MOFO......100 gallon tank, 220v and the DA still can get ahead of it.....

agree.gif

I have a 60 gallon 220volt compressor and it's perfect.--took my entire teener down to metal. I tried a used 20 gallon and it was worthless.

Where is your dryer. Most houses are wired for both gas and 220. You can run a 15' extension (welding cable) to it if it's close enough. I run my cable out the detached garage and through the "doggy door" when I need to.
Joe Bob
BTW....it IS good to have a dryer and a knockout pot...but it's also a GOOD idea to put a bit of oil in the end of ratchets and such before each use....
Dr Evil
QUOTE(Vacca Rabite @ Dec 26 2006, 09:14 PM) *

I am limited power wise. I only have 110 going to the garage (which is detached), running a 220 circut there (I'd love to do it) would require trenching under my driveway.

Anything that I buy won't be used all day everyday. After the 914 is done, the next task would be running a floor nailer as I continue to lay new flooring down in the house. Mayhaps I'll go check out HF tomorrow and see what they are offering.

I like having the week off. i need to do this more often. :-)

Zach


Uh, you got my sarcasm in my last post, right? HF will have cheap compressors, but they will not be better than the ones you saw. I just want to be clear so as to not be blamed for anything later wink.gif

Twystd1
And note the filters in the pic coming off the compressor.

Sweet.........

I have seen so many setups that have an oiler inline with the air supply.

And the guys can't figure out why all of their paint jobs get terrible fish eye.

It's because of the oil in the air lines from the oiler.....

The compressor itself puts enough oil vapor in the air lines to screw up a paint job......

Don't run an oiler in line. (not needed in a home garage scenario)

Just put a couple of drops in the inlet side of the air tool... Done...

Once airlines get oil in em... especially synthetic compressor oil with silicone in it, it's dam near impossible to get the oil out of the lines.

I used to have seperate air lines that I only used for prime and paint.
Just to be safe from fish eye problems.....

Just more useless food for thought.

C
bernbomb914
most important is how loud are they. there is a big differance in the oil bath and the oilless type. one is very loud and will drive you crazy while the other is not quite as loud check them before you buy
Bernie
sww914
I've had a Husky 220 7hp 60 gal in my garage for 5 years, I've used it for 4 complete paint jobs minus the painting (I rent a booth), countless fabrication projects, a bunch of small autobody & paint jobs, etc., etc., etc., and I've had no problems. It will just keep up with an HVLP gun, it will almost keep up with a big die grinder, a DA will work, but I need to stop and let it catch up every 5 minutes or so. It was $389.00 when I bought it. I couldn't live with anything less, but I don't really need much more. I used to have it plugged in to a dryer outlet with a 40' cord, but when I bought a house it had 220 in the garage, so all is well.
I've painted probably 50 panels here and I've never installed a water/oil trap. I keep meaning to, but it's working well so far, so why bother?
I do, however have a 30' run of pvc before the hose, angled so the water will run back into the compressor after the air cools, and that's what has prevented any water problems.
I'd do the same thing all over again.
Whatever you do, don't but an oil free compressor. Buy one with a seperate pump and motor, with a belt in between. I toasted 2 Sears oil free 6 hp 220 compressors, the ones with an integral motor and pump, while it was still under warranty. The rod went right through the piston both times, the cylinder was oval, and the plastic rings melted.
I sold the 3rd one as soon as I got it, and bought this.
Also, I run Mobil1 after about 20 hours, it doesn't coke up.
rick 918-S
The electric DA's work good also. Then you may be able to get by with the largest air compressor you can buy that will run on 110. Best to have 19 cfm for paint.
gfulcher
My compressor was built in 1946... not sure what the HP rating of the motor is, but it's big... and QUIET.. you can talk in a normal voice while standing next to it. Runs on 220 and has no problems keeping up with most jobs, regardless of tool, although I haven't tried a blast cabinet with it yet...

New garden-variety compressors, at least the ones I've found are crap, as one other said, you get what you pay for. They are loud and have no ability to keep up. Get an oldie, spend some money on new belts and rings and such and forget about buying another one for a LONG time.

IPB Image
PRS914-6
Another tid-bit to consider. If you can afford a good one, make sure you get a 2 stage compressor. This dramatically increases your storage size by using more pressure. I run 150 psi at the compressor and regulate down from there.

I also have my compressor outside the shop so I don't have to listen to it run.
Borderline
QUOTE
I do, however have a 30' run of pvc before the hose, angled so the water will run back into the compressor after the air cools, and that's what has prevented any water problems.


sww914: everything I've read says not to use pvc for compressed air. What pressure are you running and what size and schedule pvc are you using? I would like to use pvc to save some money but also like to be on the safe side.


I'm surprised someone has mentioned Home Depot and Trekkor hasn't chimed in. chairfall.gif chairfall.gif chairfall.gif
sww914
QUOTE(Borderline @ Dec 26 2006, 10:02 PM) *

QUOTE
I do, however have a 30' run of pvc before the hose, angled so the water will run back into the compressor after the air cools, and that's what has prevented any water problems.


sww914: everything I've read says not to use pvc for compressed air. What pressure are you running and what size and schedule pvc are you using? I would like to use pvc to save some money but also like to be on the safe side.


I'm surprised someone has mentioned Home Depot and Trekkor hasn't chimed in. chairfall.gif chairfall.gif chairfall.gif

I haven't read that, but I've never researched the subject either. I have 1" so there won't be much pressure drop over 30' but I don't remember if it's sch40 or sch80, it's the thick stuff you can get at the hardware store. I've worked in a bunch of body shops and at least half had PVC, the others had iron or copper. Copper is probably the best, but it's so blinking expensive that the shop owners use the smallest that they can get away with and the guy in the stall farthest away from the compressor only gets 80#, and the other guys close to it get 125#.
I'm running 150#, and maybe I can't recommend that you do the same, but it's worked for me for 2 years. In a shop, about once a year or so, the pvc will blow out somewhere and you have to shut it down for a 1/2 hour, but it's easy to fix.
I have mine at the top of the wall, so WHEN it blows it won't shoot me right in the nuts with a pile of hardware or whatever, and now that I think of it, all of the shops that had PVC had it running way up on the wall, except for the drops down to the outlets.
Twystd1
As a option for PVC.

I just got done doing a whole shop in Copper.

A friend of mines Harley shop. I owed him a favor.... KMA.gif

3/4 inch copper.. At 25 bucks a 10 foot stick. Plus all the 90s and couplers.

It cost a mint to do it.

The reason..?????????????

A 3/4 inch schedule 80, 90 degree PVC elbow shattered and nailed a mechanic in the face.

Bout an inch below his eye... Took 12 stitches to fix the wound.

The system has a constant 125PSI in the lines.

I have seen this time and again.....

And I have seen PROPERLY installed PVC air lines have ZERO problems. For years..!!!!

Most folks don't hang PVC properly. Most folks don't use primer on all joints.

Most folks don't inspect all of the plastic fittings before asembly.

And most of all.... folks thread in metal connectors too deep into the plastic female connector and put a stress point in the plastic... Thats a time bomb waiting to happen.

And the colder PVC gets. The propensity to shatter is excaserbated.
(love that word)

Me... I won't use PVC..... I don't like the odds of an occasional flying piece of shrapnel in a shop or garage.

Then again.... I am a nut case when it comes to doing stuff right.
(read: usually expensive)

Cheers and watch out for flying objects.

Clayton
Twystd1
SWW914.

I live in a mecca of chemicals. There is enough silicone in the air in the commercial area of Costa Mesa to make a painter just cry from fish eye.

The ONLY way we have been able to lower the propensity for fish eye was to either add smoothy to our paint (I hate that but it makes the paint silicone compatible)

OR: clean any oil and water out of the air system before painting anything. That made a huge differance for our final coats. less blocking... less color sanding.

I live next to the beach. Humidity changes by the hour here. salt is in the air, silicone and all kinds of crazy stuff from chemical company's and from Porterfield racing brakes corp around the corner. Makes it difficult to get a really bitchin CONSISTENT final coat.

Thats is just how it works for me....... Like you.... i am just coming from my experience...

Cheers....!!!!!!!! biggrin.gif

Clayton

morph
i use pvc to run all my air lines.(1/2 pvc is rated at 300psi) the connectors are rated twice as high.its pretty safe ,unless you wrench down to tight on the threaded connections and crack it.and it does not explode biggrin.gif it just bleeds air out the crack. just buy the pipe hangers to tack to the wall real good and your good to go. if you got allot of vibration at the tank use a flex hose from the compressor to the pvc line.i have never seen a 110 compressor keep up with a da,for very long that is.i also have air lines that are only for paint and resin spray.
james
DBCooper
The reason that little compressor said it wasn't rated for a DA sander is because of its duty cycle. It may be able to flow enough air to run the tool, but not continuously. Compressors and tools usually list a duty cycles as a percentage, like ten minutes running, five minutes down. The tank should hold enough air, in volume and pressure, to cover the five minutes it's down. If the compressor doesn't get a chance to cool then bad things happen, just like the engine in your car.

NEVER use regular schedule 40 Home Depot PVC water pipe for high-pressure air lines. I know that people have had luck with schedule 80 or CPVC, which is more malable and stays stronger at higher temperatures. But I've also heard about it exploding, too. PVC can lose half its strength with summer heat. and the combination of heat and pulse vibrations from the compressor will eventually cause it to fracture and then explode. In fact I understand that OSHA prohibits PVC in in commercial air line use. If you have any choice at all go with copper, but if you need to plumb it yourself and don't use it heavily or often at least use high pressure rated schedule 80 PVC or CPVC.

Also you should probably have an older compressor ASTM inspected occasionally. Most towns will have someone who's qualified to do the inspections. The reason is that condensation will eventually corrode the bottom of any air tank, and once it corrodes all the way through it will go out the roof of your garage like a rocket. That tends to happen at inopportune times, and will be something I guarantee you and your neighbors will never forget, even if no one gets hurt.
bmcwilli
What about PEX?

Don't shoot me...I just have been wondering if PEX is up to the task.

Thanks
736conver
Another option for air compressors is a gasoline powered one. I had one a few years ago worked excellent. Had a very high CFM output and was always able to keep up with my DA and cutoff wheel. Down side was the noise and having to add gas. But at the time I didnt have electrical out in my garage, so it worked great.
Now I have 100amp service and a nice 80 gallon compressor
PRS914-6
Regarding the PVC.....First let me say, I would use copper if you can afford it.. With that said, I used PVC. My shop is big and I have air outlets everywhere. No problems with 17 years of use at 150psi. I attribute that to several factors.

1. At each wall drop termination, I used a 2" long metal pipe fitting to an air coupling. I made metal brackets to attach them to the wall. When you pull on the lines, no pressure is put on the PVC, only on the metal to metal pieces.

2. All PVC is in the wall. No explosion worries and no sun exposure

3. The pipe and fittings were well primed and glued using commercial grade PVC cement.

If you are considering exposed PVC, and it breaks\explodes you could do some very serious harm to yourself and vehicles that are close so be careful if you do this route.
Borderline
hijacked.gif

Vacca: Sorry, I hijacked your thread, but a lot of good info..

Thanks guys!
VaccaRabite
No problem. I am reading and learning.

Zach
1bad914
Go here and ask questions about any garage subject, www.garagejournal.com/forum/ Mine is huge, 25 cfm @175 psi, 2-stage Curtis , bigger is better! I did use a Sears 25 gal 110 for years, it would never keep up with a DA, but I painted many cars with it.
VaccaRabite
Okay, so I am changing my focus here.

I would like a reccomendation for a relativly inexpensive compressor that would be able to drive a paint gun. While an HVLP gun would be nice, if they require 60 gallon compressors then I can't justify it.

Sanders and other high CFM tools are out of the scope of this search. At this point I have eletric grinders and DA sanders.

Ideally, I'd like to be abel to keep it in the 26 - 30 gallon range, as that would still be more or less portable (wheeled) and I would be able to use it for other tasks outside my garage (air nailers, floor nailers, etc.)

The short term goal is to be able to lay down primer and paint in the spring, without having to hire a pro painter. I guess what I am looking for is an economical compressor/paint gun combo that is not crap, but also not designed to be used all day every day.

Zach
morph
not to be off subject. i stand corrected,i did a small search and i guess pvc can explode biggrin.gif

STATE OF WASHINGTON
Department of
Labor & Industries

Hazard Alert
FOR IMMEDIATE RELEASE May 26, 1988


PVC pipe not to be used in compressed air systems

OLYMPIA -- The Department of Labor and Industries warned today that plastic polyvinyl chloride (PVC) pipe cannot be used in compressed air piping systems without the risk of explosion.

When PVC piping explodes, plastic shrapnel pieces are thrown in all directions.

"We're seeing more incidents of explosive failure, and we're citing more employers for using PVC air system piping," said Paul Merrill, senior safety inspector in L&I's Spokane office.

"It's probably just a matter of time before someone gets seriously injured in one of these explosions unless everyone pays more attention to the manufacturer's warnings," Merrill said.
Last year, a section of PVC pipe being used for compressed air exploded 27 feet above a warehouse floor. A fragment of the pipe flew 60 feet and embedded itself in a roll of paper. Fortunately, nobody was in the area at the time.
A PVC pipe explosion in a new plant in Selah broke an employee's nose and cut his face.

PVC piping buried 3 feet underground at a Yakima manufacturing plant exploded, opening up a crater approximately 4 feet deep by 3 feet across.

back to your question most paint guns that are not name brands (spendy) are chinese knock offs. i have four binks knock off in service for the last five years.and i will retire them after the the end of 06.with flawless service. as far as the compressors avoid the oiless ones there junk.
james
Matt Romanowski
For the most bang for the buck, look for something used. If you have a 914 and are used to rebuilding things, a compressor is easy. Look for the biggest you can afford. I've never heard someone complain that their compressor makes too much air....
jsteele22
Wow, a really great thread. I wish I had gotten this kind of advice on how to pick a wife ! (J/K)

I just wanted to expand a little on the 110/220 issue, in case it's useful to anybody. (Read at your own risk.) Any house in the US with electrical service already has 220 V service. What you get are two distinct phases (call 'em A and B ) that individually wave up (positive) and down (negative) with respect to neutral/ground (zero). The big (only) difference between A and B is the timing; A is pos while B is neg, then they cross zero at the same instant, then A is neg while B is pos. All of the 110V circuits in a house (plugs, lights, disco ball) have their hot wire hooked up to one or the other phase. In order to use a 220V appliance, you just need 2 hot wires : one for both A and B.

The only absolutely safe and legal way to get 220V is to have a certified electrician pull a permit, do the work, and have it inspected. Ouch. But if you just want to run a 220V appliance on an occasional basis, you just need a hot line from phase A and B to it (plus neutral, plus ground). If you already have a 110V outlet, you are halfway there. In principle, all you need is an extension cord (make sure it's rated for enough current) and plug it into an outlet fed by the other phase. (You can check with an A/C voltmeter. Each hot wire will read 110V with respect to neutral, but reading from one hot to the other will give 220V, or zero if they are the same phase).

This will work, but it's a little dangerous. To be safe, you need a way to make sure that if one phase (say A) draws too much current, that BOTH phases will shut off. You do this by making sure that the circuit breakers in the main panel that feed your A and B phases are next to each other. (The breakers in a panel always alternate A/B/A/B/....). Then, depending on the brand, there's usually a way to mechanically link them with a piece of wire or a pin so they can only switch on and off together.

Based on the above, a slightly more elegant (but still cheap and not entirely legal) way to do the same thing would be to buy a 220V breaker (a pair of adjacent 110V breakers permanently linked together), a box of Romex (10 gauge, 3 conductors plus ground) and an electrical box with appropriate socket, and make a custom extension cord. When you plan on using the compressor, you can hook up the wires (A,B, neutral, ground) to the main panel and you're good to go.

I'd say if you decide to do something along these lines, find someone who has some experience with home wiring, or buy a book, or both. My main goal here was to point out that the lack of "real" 220V service isn't an absolute roadblock to using a decent compressor or welder for the occasional DIY CSOB. Hope it helps.
orange914
1 get stand up not space consuming laydown style
2 120v not 220v its much more portable for around the house projects
3 DUEL stage brings air pressure up quicker and keeps more constant
4 DONT get oiless -way loud!!!- stromberg.gif
5 add adjustable pressure regulator inline if not equipt already
736conver
QUOTE(Vacca Rabite @ Dec 27 2006, 11:44 AM) *

Okay, so I am changing my focus here.

I would like a reccomendation for a relativly inexpensive compressor that would be able to drive a paint gun. While an HVLP gun would be nice, if they require 60 gallon compressors then I can't justify it.

Sanders and other high CFM tools are out of the scope of this search. At this point I have eletric grinders and DA sanders.

Ideally, I'd like to be abel to keep it in the 26 - 30 gallon range, as that would still be more or less portable (wheeled) and I would be able to use it for other tasks outside my garage (air nailers, floor nailers, etc.)

The short term goal is to be able to lay down primer and paint in the spring, without having to hire a pro painter. I guess what I am looking for is an economical compressor/paint gun combo that is not crap, but also not designed to be used all day every day.

Zach



Whats you budget?

VaccaRabite
QUOTE(736conver @ Dec 27 2006, 05:56 PM) *

QUOTE(Vacca Rabite @ Dec 27 2006, 11:44 AM) *

words words words.....
Zach

Whats you budget?


Ideally ~400 max for a compressor, with a paint gun that works well as cheaply as possible.

Zach
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