Setting up a Sandblaster - Compressor Size

[smallbitz]

I plan on doing just basic clean-up of glass with my sandblaster. No heavy duty etching or carving. Space is a real concern in my studio. I have the HF 40 lb. syphon cabinet, but am curious about the size of the compressor I can get away with. I see the 33 gallon from Sears http://www.sears.com/craftsman-33-gallo ... ockType=G2 which looks like about the minimum that I should have. It's just soooo big! Do I really need one that BIG? I also see this one from Lowes http://www.lowes.com/pd_476123-30449-03 ... facetInfo=. It's much smaller at 5 gallons, but has basically the same cfm's as the 33 gallon. Would this work for what I need?

Does anyone have any experience with the smaller compressors? Sure could use some advice here...I know it's always best to 'buy bigger than you need', but space sometimes dictates otherwise.

[Rick Wilton]

Those are both "oil less" compressors, these are REALLY noisy. They also are designed to only run for 15 min tops out of 30 mins. They NEED to stop and cool off regularly or they will overheat and wear out really fast. Oiled compressors are designed to run for much longer times without issue. That being said the two compressors seem to offer similar spec in regards to air output. The big difference is they lack of a large tank on the small one, this will mean that your compressor will be cycling on and off much more frequently than one with a large tank.

I would think you'd be okay if you are using this for short blasting sessions for 15-20 minutes every once and a while. If you are planning on blasting for an hour a day regularly then you should get something more substantial.

I know a very well regarded fuser who frequents this board who used to blast with a even smaller compressor than either of those. He made some amazing work with a pancake compressor.

[smallbitz]

I didn't realize the oil-less compressors were that much louder. Do the ones that require oil need much maintenance? I really don't think I'll be using it that often (maybe once or twice a week, for 15-20 minutes). I would sure like to get away with a small QUIET one, if at all possible.

Thanks for the info, Rick!

[Rick Wilton]

I don't think they require much maintenance, I change the oil in mine MAYBE once a year and I use mine for a hours a day, most days. They recommend changing the oil more regularly but I don't bother. My current compressor has lasted for over 10 years being used and abused. I have a small oiless compressor that i use at home to fill tires and to operate a small nailer, it produces MAYBE 10% of the air my regular one does and it is easily 2 or 3 times as loud.

[Brad Walker]

Although it's generally true that oil-less compressors are noisier than regular ones that require you to change the oil, some of the newer oil-less compressors are actually pretty quite. The two mentioned above are rated at 60 and 68 decibels, significantly quieter than (for example) Ingersall Rand's 5HP 60-gallon SS5L5, which is rated at 78 dB. You can't be 100% certain that the specs are accurate, but on the surface it sounds (no pun intended!) like the oil-less compressors mentioned here might actually be reasonably quiet. (60 dB is normal conversation, 70dB is twice as loud as 60dB and 80 dB is twice as loud as 70dB, or as loud as a freight train from 50 feet away.)

To me, the big question is the tank capacity on the small compressors, but if they're only being used a few minutes at a time they should work ok. They won't last nearly as long as a larger compressor that requires changing oil, but they probably wouldn't be used as much either.

And, like Rick, I only change the oil in my compressor every year or so. It's easier than changing the oil in a car, mainly because you can change the oil while standing up.

[Valerie Adams]

I just bought a 'small' 27 gallon compressor and was shocked with how big it is! I don't have experience with them so I didn't anticipate it being so HUGE!
The footprint of my vertical unit is about 2.5' square. Luckily, it's on wheels so I can tip it and roll it around.

[smallbitz]

That's what happened to me, Valerie. I was going to order one online but wanted to see it in person first to get an idea of how it would fit in my studio. When I went to the store, I was shocked at how big the 33 gallon size was! HUGE! Between the SB cabinet, dust collector (shop vac) and the compressor, I need to add on to my studio to fit in all that equipment;) I'm actually going to put it on my porch for the time being.

I think for what I'm going to use it for, I'll go with a smaller one for now. Noise is also a concern for me, and the reviews on the small one were that it was relatively quiet.

Thanks Rick, Tony and Brad for your help and info. I'll post how the set-up works for me when I get it all together and working!

Dot.

[Kevin Midgley]

For years I used a bostich oil filled 2 gallon tank compressor for light etching of designs using a pressure pot and at a pressure of less than 20 PSI and the smallest carbide nozzle possible.
You cannot do carving with a little compressor as there just isn't the volume of air available. Compressor would run pretty much continuously not super loud but still worthy of ear muffs. I think the motor was/is Italian. A tiny carbide nozzle and low pressure is key or you can easily blow away fancy finely detailed sand blasting resists.
Now with a large compressor I can fill the tank with air and shut off the compressor and blast at low pressure for 15-20 minutes in silence. When it is noisily running for the 5 minutes or so it takes to fill the tank it is time to go and get a cup of coffee.
If you want depth carving, even a large compressor will run often in order to maintain the 90 + PSI required to do the work.
As described and set up, a teeny compressor will work for delicate etching or kiln wash cleanup work for a hobby studio. Your mileage may vary depending on where that motor was made and your regular or not checking of oil fill levels. Check if it is capable of running continuously. Many of these small units are used by contractors for use with air nailers and are designed to run pretty much continually.
I don't think Bostich, from looking quickly online, still sells an oil filled unit. Stick with an oil filled one if you want any sort of longevity out of a pancake compressor.

[Morganica]

That's what happened to me, Valerie. I was going to order one online but wanted to see it in person first to get an idea of how it would fit in my studio. When I went to the store, I was shocked at how big the 33 gallon size was! HUGE! Between the SB cabinet, dust collector (shop vac) and the compressor, I need to add on to my studio to fit in all that equipment;) I'm actually going to put it on my porch for the time being.

I think for what I'm going to use it for, I'll go with a smaller one for now. Noise is also a concern for me, and the reviews on the small one were that it was relatively quiet.

Thanks Rick, Tony and Brad for your help and info. I'll post how the set-up works for me when I get it all together and working!

Dot.

When I first decided to try sandblasting years ago, I called HF and asked them if they thought a 60-gallon compressor would fit into my car (a Nissan Maxima). Dead silence on the other end of the line for a few seconds, then the guy says, "I can't tell. You'll need to come in and see it."

When I got there half the employees were in the compressor aisle, waiting to see my reaction. Uhm...no.

[Joyce Walters]

My thanks goes to Kevin. I read your post carefully, twice, and I think you gave me the correct answer for my work.
Again, thanks for the money and time saved.
Joyce

[Tony Smith]

Just to be clear Joyce, the only way you can use a pancake compressor is with a pressure pot (not a siphon blaster), and lots of patience. It's best if you have small pieces to blast.

Tony

[Joyce Walters]

Thank you, Tony, for taking time to clarify.
I do mostly small pieces, but occasionally want to sandblast the devit off plate or bowl blanks.
I will continue to consider options.
Need and want are 2 different things, eh?
with appreciation for all the good help on this forum, Joyce

[smallbitz]

UPDATE-
Well, got everything set up and it's working great! Thanks so much for the input and advice from everyone. I just wanted to let you know what equipment I ended up with, and is working for my situation.

I went with the HF large blasting cabinet (quite a pain to put together, but the price sure was right!). I sealed it with silicon as I went along, and no leaks at all.

The biggest decision that I was asking the board about was the compressor. I ended going with a Kobalt 2 HP, 5-gallon compressor from Lowes. http://www.lowes.com/pd_476123-30449-03 ... facetInfo= The fact that I needed something relatively small and quiet sold me on this unit. I also wanted to get it somewhere where I could return it if it was not going to be beefy enough, as opposed to ordering it online. It was the right one for me. It is quieter than I had expected, very easy to use and seems to have more than enough power and running ability for what I need it to do. Been using it for about 10 days now to see what it can do, and it has done everything I have asked it to do from cleaning off kiln wash on pot melts, putting a matt finish on a bowl, blasting clean twenty five pattern bars, etc. This is exactly what I needed it for. I won't be doing deep etching, so not concerned with that type of power.

Perfect for what I needed!

Using my old shop vac as the dust collector.

Purchased the compressor on sale, the blasting cabinet on sale (and 20% off coupon at HF!), 50lbs. of silicon carbide for 1/2 price, used my old shop vac and purchased a new one at HF. Total for everything - under $600.

Many thanks to all gave me info to make my decision. Very happy with what I have purchased - especially considering I really knew nothing before I began my search!


Dot.

PS- One final (maybe) question - what kind of cleaning do I need to do before firing AFTER sandblasting? I know that sandblasting is used to 'clean' the glass, but you still need to do your 'regular' cleaning - right?

[DonMcClennen]

Re: Cleaning... yes make sure you give the blasted piece a good scrubbing with soap and water and rinse well. Unseen sandblast dust that is not removed gives refired pieces a dirty look!

[Tony Smith]

I'm glad to hear your system is up and running. The HF cabinet is really a pain to assemble, but you did it right by sealing every seam.
I've always rinsed under running water while rubbing the surface with my fingers. You have to remove the dust to avoid getting a haze after refiring, and I've never had a problem. Do not use glass cleaner and paper towels. It just doesn't get rid of all of the dust and usually shreds the paper towel.

Tony