Suitable Compressor?

[69_Dream]

Alrighty, before I start I have to say I know nothing about these things... but I know I gotta get one (kinda how I felt about a vette).

I'm looking into picking up a cheap sandblasting cabinet (no more than $200) for the garage. I know I need a decent compressor, but exactly how decent does it really need to be?

I'm definately looking at the lower end, something with a couple horsepower and less than a 10 gallon tank. I keep reading about CFM and how I should want (or perhaps need) 8-10 CFM at 90 PSI. Is that excessive? I primarily plan to use this for sandblasting, limited use of impact gun, air drill and maybe a little sanding. I don't intend on painting in the near future, but who knows? Again, sandblasting is the real reason for the purchase.

Also, what's everyone's opinion with Oil Free, Direct Drive? Should I be concerned with pump RPM?

Sly

 

[69_Dream]

Still nothing?

Anyone have a good setup they'd recommend?

I don't think I've ever had a post last this long without a reply...

Sly

 

[Piet]

Look at the previous post on air compressors.

I have a direct drive oilless... 6 hp 27 gal tank... no problem
6.0 CFM @ 90 PSI good enough to run what I need
For "hobby" sandblasting that should be fine. (may need to let the tank recharge every once in a while)

 

[JohnZ]

Alrighty, before I start I have to say I know nothing about these things... but I know I gotta get one (kinda how I felt about a vette).

I'm looking into picking up a cheap sandblasting cabinet (no more than $200) for the garage. I know I need a decent compressor, but exactly how decent does it really need to be?

I'm definately looking at the lower end, something with a couple horsepower and less than a 10 gallon tank. I keep reading about CFM and how I should want (or perhaps need) 8-10 CFM at 90 PSI. Is that excessive? I primarily plan to use this for sandblasting, limited use of impact gun, air drill and maybe a little sanding. I don't intend on painting in the near future, but who knows? Again, sandblasting is the real reason for the purchase.

Also, what's everyone's opinion with Oil Free, Direct Drive? Should I be concerned with pump RPM?

Sly

Sanding and blasting are the two most demanding applications for a compressor; you need at least 6.5hp (220 volt) and a 60-gallon tank to support that kind of usage. Anything smaller, and it'll run all the time, you'll have to wait constantly for it to catch up, and you'll burn it up in no time.

Check out Harbor Freight, Home Depot, Lowe's, etc. - you can find many different brands with 6.5hp, 60-gallon vertical, 10-12 scfm @ 90 psi for around $400-$500; get an oiled compressor with cast iron sleeves and belt drive. If you buy anything less, it won't meet your needs and you'll be sorry you bought it in short order. There's no free lunch when you're planning air-demanding applications.

 

[69_Dream]

Thanks for the replies guys. Good advice John, hate to buy something I could potentially burn out or keep having to swear at it

I may have to wait a bit longer, at least it'll give enough time to seek out a proper sandblasting cabinet.

Any problems with buying a used compressor? I had seen one a few weeks back, but it was huge... thinking of it now, I think it was 60 or 80 gallons.

Sly

 

[IH2LOSE]

69 dream
Do as I say (suggest) not as I have done

I have treid in the past purchasing a smaller compressor then what I really needed it for.I also purchased a smaller sand blast cabinet then what I should have.

So to make a long story short

Get a HIGH cfm compressor the first time.I have upgraded 2 compressor so far 1 just because I was cheap.and the secound one I purchased because I fealt I did not want a large compressor taking up space in my allready cramped garage.I wasted alot of time and money monkeying around with too light a cfm compressor.I now have a 7 hp compressor with a 60 gallon verticale tank its rated at 13.5 cfm at 90 psi. it keeps up perfectly with my blaster cabinet and regular blaster

as for the cabinet blaster get a BIG ONE I know the price goes up acourdinly.i say this because again the one I purchased is to small (it was a bench top blaster) and when you look at the dimentions it seems big enough but when you put some thing in it ,it tough to move the blaster gun far enough away from the part to work on it and if the part is in your hand and you blasting it the blast material bounces off the part (this is normal) and hits the plexiglass window and dull it out so you cant see it too well.

Now when I was making my purchase I had figured I would not use it that much and it was more of a luxury then a necessady,once you have one in your garage you will use it all the time and thats why I recomend to purchase a big one right off the bat.

Just to let you know I do plan on exspanding my garage before the winter and one of the first tools I will bring in is a floor mounted large blast cabinet.

Good luck I wish some one would have explained this to me before I made my purchase.

 

[drags1998]

Do yourself a favor!!! DONT BUY A SMALL UNIT!!!!!!!!! My Home Depot has a nice Med. duty unit for some where around 350.00 I know thats more than you want to spend rite now, but this is what I would recommend as a Min. size!!!! Good Luck!!

 

[69_Dream]

Thanks IH2LOSE, that's precisely why I asked the question on this forum. You guys have been through it all and I'd hate to be cheap and get something that will frustrate me, in the end having to buy another (so much for being cheap ).

I had already decided to wait until I could afford a larger compressor. 6 HP, 60 gallon, 10 CFM @ 90 psi seems to be the norm, or at least the minimum. It now looks like I'll wait on the cabinet too... better to do it right the first time.

Thanks again all.
Sly

 

[Tom Bryant]

All of the air tools you will buy have minimum requirements listed on them. As John said blasters and sanders use a lot of cfm. Get something that puts out more than your highest usage tool. Here's what I have. The smaller one is a Sears I bought in '79 or so. The label is gone but I think it is around 9.5 scfm@ 90 psi. It is a 3 hp 30 gallon 220 volt had has sanded and painted a lot of cars with only air filter and oil changes. It is possible to get ahead of it when sanding and I often stop to give it a break. It would not keep up with a blaster if you were doing more than just little stuff. It works great for most jobs and air tools though.

The big one is an 80 gallon 5 hp 2 stage industrial that puts out 17.9 scfm@100 psi. It cycles on at 140 psi and off at 175 psi. It may be a little overkill but it was my late father-in-laws and has very little hours on it. From new it had a problem with the pressure switch shutting off. I looked around on line at at local businesses and found switches to be from $46. to $55. I got one on Ebay for $12.50 plus $9. shipping and it works perfectly.

They are mounted on blocks of wood. This makes them easy to drain and they don't go for a walk while they are running. A lot easier than bolting them to the floor. Also I have them in the double garage where the drivers live. This gives them a source of clean air and keeps it quieter in the shop that's through the door in the right of the picture. I still need to run air lines into the shop and mount the dryers.

Tom