Quote Originally Posted by spluppit View Post
Charlie as i know your build (as i made some of the parts for you) It looks like your orientation is correct in my book ( as you stand in front of the machine). In the case of your machine the longest travel is left and right, this would be your X. The head traveling away from you and towards you is your Y. The Z Axis as always never changes and is is the head up and down directions. This is the standard configuration for any milling machine. In the technical sense the X and X doesn't really matter as long as you know what each one is. As i described above is the standard configuration that's been used for the last zillion years.
It's not about which is the longest axis, it's about orientation. The one parallel with your belly is the X, the one moving AWAY from your belly is Y and the one moving towards your head from your feet is the Z. Plus (increasing value) is moving from left to right, from nearest to farthest (away from you) and from lowest to highest, assuming the lowest is always zero. Just look in any maths book, it should be like that in every one of them. ...but you may have another book, the one with a printing error, because his orientation is indeed wrong regarding Y. But it really isn't a big deal, except that it is a bit confusing if he is learning the wrong way or talking to other people about axis orientation. I don't know where Y is increasing when moving towards you, and I really don't think it's been like that for any number of years, let alone zillion...