![]() The X axis is usually the longest axis perpendicular to this Z axis. The General convention for machining is that the Z axis is parallel to the axis of the spindle rotation, which is often vertical for a milling machine or horizontal for a lathe. These motions are designated by convetion X, Y and Z. This makes no difference when creating the NC program, since the tool motions will be described relative to the part in either case. In some type of machines the cutter will move, and in others, the part will move and the cutter will remain stationary. In each of these machines, the motion of the cutter relateive to the part is described using a 'right hand rule' rectangular cartesian coordinate system as has been used through this Guide. 'Several different types of machining operations can be performed by NC machines, such as milling, lathe turning, flame water-jet or laser cutting, bibbling, etc. The book is from 1989, however perhaps it still holds true, or at least shows some history of the terminology I am posting the entire excerpt from the chapter on NC machining, the section is called 'Axis of Motion', because I would not know how to begin to summarize. I found the reference I was thinking about and needless to say, I was off a bit. An Axis is defined as: A straight line about which a body or geometric object rotates or may be conceived to rotate. If you get quite imaginative you can obtain some very intricate 3D relief’s following vectors using only a 2D program like Part Wizard So using a 2D tool path you wind up with a 3D shape. Now if you cut out the same shape but use a bit with a profile such as an Ogee or some other shape it will no longer be just a flat silhouette but become three dimensional. ![]() In other words if you cut out a silhouette with a straight bit you have a flat shape. Now a 2.5D is a method of creating a 3D affect while using a 2D strategy and only needs a 2D tool path. The shape of the bit alone does not contribute to creating the 3D affect but carves the shape following a 3D tool path created using some 3D cadcam software The operation of creating this dimensional affect requires the tool to move in all three plains using a bit with a simple shape. ![]() Where as a 3D operation creates a relief having all three dimensions X, Y and Z and requires a 3D program. In 2d you are only cutting out a silhouette defined in the X and Y plain using a 2D program. It has always been my understanding that when cutting parts from flat material where you only cut around the part like a cookie cutter was referred to as 2D. I know there is a much more sophisticated (and presumably more precise) way to achieve this with sb than actual rendering the entire tool path in corell but do not know what software to use or the process to do it. I use turbocad, autocad and corell as I still have to occasionaly trick my laser into doing something useful but my only experience going for the effect I want is (for the laser) using corell to add contour lines out from an autocad drawing with a spacing equal to the laser 'kerf'. What sw packages are useful for this? The parts I'm cutting are simple enough to do with just the shopbot control laungage so I have no investment is SB or sign specific packages. ![]() It's easy enough to engrave lettering with a vbit and typesetter but I'd really like to 'reverse the relief' (certianly incorrect terminology) and have the letters raised. Lurking in this forum, I'm fascinated by some of the work you guys do. Gotta new PRT96 (actualy, just new to me - I bought it used) and have it running fairly well at the job I intended for it (still have a bit of tinkering to find the best bit for the soft plastic we're cutting, but the machine is working well).
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