Cindy,
The process of engraving large stones and granite pieces will require a different approach to your set-up than that used for carving smaller gift and award items.
Larger pieces will require a method of transporting and handling the material. The blasting process will require an enclosed ventilated room, or an outdoor blasting area. This process will also require a grit that is more coarse (150-grit). That grit will also be dispensed at a higher air pressure.
Larger products will also require the use of a vinyl plotter to cut the designs out of masking materials. Smaller pieces can be masked with photo-resist materials or laser mask.
My experiense has only been in the gift and award type sandcarving. For this type of engraving I would recommend a pressure-pot blaster rather than one that is siphon-fed. The pressure pot blaster will maintain a more consistent pressure and media flow. It also allows you better control of the pressure at which the media is dispensed. This is an important factor when you get into the more artistic aspects of sandcarving such as shading. Pressure-pot blasters also tend to be much faster than siphon-fed.
If keeping a clean work area is important to you, I would recommend a system that has the pressure pot built right into the cabinet. This allows you to refill the pressure pot with abrasive without creating a billowing cloud of dust in your work area. It is also a more efficient design.
The second most important factor is the air compressor size. www.sandcarver.org has some great articles on this subject. The bottom line is that you don't want a compressor so small that you are having to spend half of your time waiting for it to re-pressurize. Time is money! |