Need air compressor

A really big one. Your blaster should have a CFM rating. The compressor has to be able to keep up with that flow. Probably a minimum of 13 CFM at 90psi

CFM? What's that? I am trying to get the compressor w/o help from DH since it's *supposed* to be a gift. I got the sandblaster without even knowing it needed an air compressor to run! There is NO paperwork inside the box with instructions &/or ratings, but after calling the mfg they are sending a manual out.

Thanks for the reply, Rex. djh

Rex wrote:

Sandblasters blast sand by means of a flow of compressed air. That's why a sandblaster needs compressed air to operate. Compressed air is produced by air compressors. Depending on how much compressed air is needed, you may need a large or a small compressor. Compressor capacity to deliver compressed air is measured in cubic feet per minute (CFM). You need a compressor that can supply at least as much cubic feet per minute as the sandblaster is using.

So, find out how many CFM is the sandblaster using, and buy a coimpressor that can deliver more CFM.

Do not buy direct drive compressors, as they will drive you bonkers with extreme noise.

Buying a compressor is a v ery important decision and if you buy a bad one, you will regret it.

i

Also, let the single members of this newsgroup know if you have a single available sister.

i

Are you positive he doesn't already have a compressor? They are a pretty basic tool which most tinkerers acquire early on.

If so, it may still be too small. OTOH, if he expressed a desire for a sandblaster, knowing a gift occasion was coming up, surely he would have mentioned that.

Does DH have a local friend you can call on to identify whether there is a compressor lurking in the shop, and of what capacity?

It may take a very large (read expensive) compressor to keep up with a sand blaster. It's possible to run it from a smaller one. He would run the sand blaster for a while, then wait for the compressor to catch up, then he could run for a little while longer.

10 years ago I bought a Craftsman compressor, (220V, 5HP, 33 gal tank, 10 CFM @ 90psi) so that I could blast, specifically, bicycle frames.

With this, I can either use a cabinet or use it out in the open.

It has worked well for me.

Lewis.

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Hey Iggi, my hat is off to you for the couteous, detailed and 'spot on' reply to the original poster. Nice going!!! Ivan Vegvary

Ivan, thank you very much for this compliment!

i

Return the sand blaster and buy a bunch of wire brushes!

(aside original poster) Tom sells wire brushes

The air consumption (CFM) is based on the nozzle orifice size.

The post reminds us of the guy that gets a $10 computer game for Christmas and now has to go out and buy a $1,000 computer to play the damn thing, doesn't it?

You need a lot of air volume to run a sandblast gun - but we need to know which blaster you got for him to tell you HOW big. Do you have a make and model number? Or give us the auction item number if it was an E-Bay auction.

If this is a small pressure tank blaster - which looks like this:

they'll have the air consumption specs in the instructions.

Note the wide range of air consumption - anywhere from 6 to 25 Cubic Feet per Minute (CFM) depending on whether you use the little nozzle for delicate work, or the big one for trailer frames. If he uses the big nozzle that needs 25 CFM all the time and the compressor can't keep up, he'll have to stop and let the pressure build back up - Trust me, that waiting around part gets annoying REAL fast.

Compressors are rated at Standard CFM at a certain pressure. The bare minimum for a Home Shop running a sandblaster is a 4 to 5 Horsepower unit. 10 to 12 CFM @ 90 PSI.

WARNING: We'll tell you what he really needs to use it properly, you'll look at the price tag, and freak - Guaranteed. Then again, I can guarantee that he freaked when he saw the price tag for the Wedding Ring, and that all worked out for the better... ;-)

Unfortunately, Good ain't cheap, and Cheap ain't good. Plan on spending at least $500, if not $800. But if you pull this one off as a surprise, he's going to know you REALLY care - His face will light up like Christmas in January.

Using Harbor Freight again for easy examples, these will work:

5 HP will work for all but the biggest jobs:

7.5 HP - Slight overkill, but will run that sandblaster continuously:

You need the 7.5 HP to run the BIG 1" Industrial impact wrenches to change the rear tires on that tractor. The 5 HP will work fine, but he'll have to pause two minutes between each nut to build up air.

You want these features: Two stage pump (tank stores more air at 175 PSI than at 120 PSI) Oil lubricated cast-iron pump (lives longer - rated 10,000 hours or

15,000 hours lifetime before rebuilding needed) Belt drive (MUCH quieter when they run slower) Big vertical storage tank (easier to find a space for)

Where do you live, and what stores are nearby?

We can make more specific suggestions on what to get, and the local store can deliver the "Surprise" to the house and put it in the corner of the garage all ready to go - Huge Red Bow not included. Call an electrician to wire it up.

Yes, that is a LOT of money - more than the sandblaster it runs. But you only need to buy the compressor once, and it lasts 30 years for normal weekend use. And that one compressor does many things around the house - impact wrenches, power ratchets, drills, sanders, fills bicycle tires, paint spraying, caulking guns, grease guns...

You can even use it for *your* hobbies - air nailers and staplers for easy furniture and cabinet refinishing and repairs, put up Crown Molding and Chair Rail in the living room, etc. A few hundred feet of air hose is cheap, and will reach anywhere in the house or yard. A 5-Hp compressor will run quite nicely on a standard 30 Amp 220 Volt clothes dryer outlet circuit, and it's about the size of a water heater for comparison. Just place it next to the clothes dryer in the garage, and you can unplug the dryer and plug in the compressor.

If you use a gas clothes dryer, the electric dryer outlet in the garage will be free full-time, which is more better... ;-P

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WOW! What a comprehensive answer - thank you for taking the time to post it, Bruce.

Thank you all for your answers - except the wise guy who suggested wire brushes!

Here is the unit:

I didn't buy it from Amazon.com but it looks identical. Still waiting for the manual that wasn't included in the box for the CFM rating.

Thanks for giving me a price range and links, too. I live in Harvard, MA which should tell you nothing is nearby ;^) The closest "major" city would be either Fitchburg or Worcester, MA. Oh! Or Nashua NH.

I will ck out the Harbor Freight links. The dryer is in the basement so he can have a dedicated outlet for the compressor (when the electrician puts it in, that is) in the garage. Thanks for that info, too. Wouldn't have known to get an electrician; thought it could just be plugged into a standard outlet.

djh

Bruce L. Bergman wrote:

Some compressors can be plugged into standard outlet, but they are limited to about 1.5 horsepower output (real horsepower, not "Sears horsepower"). Beware that a lot of compressors come with inflated and false horsepower ratings. (like "6.5 maxumum developed HP, plugs into standard outlet") The simple rule of thumb is that nothing over 1.5 HP can run on a standard outlet. If that's enough for you, great, if not, you need to set up a higher power circuit to run your compressor.

i

That's a small thing, may be too small for the intended purpose. Probably OK for things about the size of a book, but it will run out of sand pretty quickly. The good news is it won't take a big compressor.

For about the same money, you could buy something like this:

....which would be good if one has an old rusty tractor, for example

Yes Tom, it does remind me of that. But just as the $1,000 Personal Confuser^w Computer can be used to do many other things than "just play $10 video games", a good air compressor can do much more than "just run a sandblaster".

It can run an air drill with one of your wire brushes chucked in it, right?

Flybaby: Tom sells Excellent USA-made wire brushes that last much longer and work much better than the crud imported from Taiwan.

When you sell wire brushes they're always the first, best, and only solution to every problem - even when they aren't. ;-p This is a corollary to "When your only tool is a hammer, all your problems look like nails."

Tom was trying to be funny, but it might have gone right over your head without the background information. I don't want you freaking out now...

And having a few knot-wire wheels would be great to knock off the majority of the rust from the flat areas of the trailer chassis very quickly, before breaking out the sandblaster to do the finish work - but I'd use an electric 4" angle grinder to do the work rather than air powered tools, more efficient that way.

Big problem with wire brushes is getting into all the corners and crannies, so you need both the brush and sandblast solutions to get the total job done quickly and efficiently. And not leave little rusty areas in the corners that'll grow under the new paint and make the whole effort pointless.

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Using an angle grinder with knotted wheel angle grinders, is HIGHLY recommended!!! It';s a very fast and safe way to remove a lot of rust in a big hurry!

i