I use this on a Porter Cable 4.5" sander without the guard for carving. This is not for boys and studious types. If you have no experience with power tools you better pass on this as it requires a stout pair of hands and small increments of cutting. You can easily chop off something of your anatomy if you are not careful. I don't know if using the guard would be any safer. It does cut like hell though but I settled on using about 1/8" sideways cuts which did not scare me to death if otherwise. Hard bracing the forward hand onto the bench while arcing the cutting with the other hand works just fine. Both hands on the grinder is a must and the work must be clamped to the bench or it will fly through the nearest window. You must use a full face shield as the chips are aimed right at your eyes. I really like these things but they do scare the hell out of me. The diameter of the tool was 4 inches but I noticed that the wood stores have the 3 inch models with a different name, (Squire)