I have a short set, all about 3/16ths, so they are clear of the workpiece automatically. With 1/4 inch MDF for your pattern. For loinger bushing collars, use thicker MDF for patterns, or grind the collars down. Of course, with most patterns, you're using a bearing as your guide and pre cutting most waste away on the workpiece with a band saw or jig saw.
There are other uses where a bushing is good, but you must also make certain the collet is centered in the base or you will have wandering lines unless you keep the router oriented the same way throughout the cut--that's if the collet, bit and bushing are not centered
There are other uses where a bushing is good, but you must also make certain the collet is centered in the base or you will have wandering lines unless you keep the router oriented the same way throughout the cut--that's if the collet, bit and bushing are not centered