An air compressor is a vital piece of equipment for abrasive glass etching. It is important to select a good one for your use, as it can save you a lot of money in the long run. If you pick the wrong one, you will probably have to replace it in a short time and it probably won't do the job you need for efficient etching.
||This is a typical light duty, stationary piston compressor with upright tank, about 4 1/2 feet tall. Stationary compressors are generally best, because portable compressors usually provide too little air for continuous blasting.
Here are some basic considerations in selecting a compressor for your glass etching equipment
It doesn't matter what kind of blasting equipment you have, an air compressor is necessary to provide the power for the blaster. The air output of the compressor in cubic feet per minute (CFM) at a given pressure (PSI or pounds of pressure per square inch) must be matched to the air consumption of the sandblaster for the best efficiency. When looking at compressors, the air output is usually stencilled on the compressor's air tank or it is printed in the operating manual.
The air consumption of any blaster can be figured from the air requirement chart on the nozzle page. Find the nozzle size that comes with the blaster. The chart will tell you how many CFM are required for continuous blasting at a given pressure. Keep in mind that, as you use the nozzle, the orifice will enlarge continuously, consuming ever increasing amounts of air. When the nozzle enlarges to the point where it is consuming more air than the compressor produces, the compressor will run constantly, losing pressure and overheating in the process. When the compressor runs almost continuously, it is time to replace the nozzle in order to save wear on the compressor.
You may be tempted to get a smaller, lower priced compressor in the beginning. This may be OK when you are starting out as a hobbyist, but not for someone wanting to work semi-professionally or professionally. A small compressor may save money initially, but it will cost far more in wasted time waiting for the compressor to catch up.
It will also cost more money on wasted nozzles. Most people doing decorative sandblasting use 2HP to 5HP compressors and pressure blasters with 3/32" nozzles. Using a 2HP compressor and silicon carbide as an abrasive, a ceramic nozzle will enlarge to the point where it needs to be replaced in about an hour. An industrial 5HP compressor provides enough air so you could use the nozzle 2-3 hours. If you only blast 5 hours per week, you would purchase 260 nozzles in a year with the 2HP compressor or less than 130 with the 5HP compressor. At approximately $3.25 per nozzle, the 5HP compressor will save you at least $423 per year. Those savings alone would pay off the extra cost of the larger compressor in a couple of years. (Yes, carbide nozzles last longer, but they cost more, too. So if you compare apples to apples, the savings remain the same.)
*Do you need a Comprehensive Guide to selecting an air compressor?
There are many other important considerations to selecting a compressor than we can present here. Things like the difference between single stage and two stage compressors or the difference between single phase and three phase electricity for the compressor motor. Other considerations include air tank size, type of lubrication for the compressor pump, whether belt drive or direct drive is better, the service factor of the electric motor, and more.
In addition, we are only considering piston compressors here. Although these are by far the most popular types of compressors, there are at least 4 other major categories of compressors. Other types of compressors are built for heavy duty continuous use or for very quiet operation, but generally cost much more.
This additional information is not highly technical or difficult to understand and we think you will be able to make a better decision if you know it. To find out about this additional information you can do several things:
- Take one of our 4 day Professional seminars (compressor information is included)
- Get your glass etching equipment from us! No, we don't sell compressors, but we do offer compressor assistance to all our equipment customers
- Consult a local compressor specialist who may take the time to explain all the details. Be careful because these folks will be trying to sell you a compressor!
Learning a little about compressors will be well worth your time and money!
(Some other questions you may want to know: Would you only use an electric compressor for glass etching? What about using a gas engine or diesel compressor? What kind of compressor do you need for On-Site blasting? What about an air compressor for micro blasting or airbrushing? Should I order a compressor from a discount warehouse out of state because the price is cheaper. . . )