I would like to continue the discussion from 2386
here in the forum because it is easier to include images and videos.
I should say first that I am not a professional machinist.
I would like to add some observations and thoughts to the discussion:
1. What a great video from sliptonic. Great idea and shown very very convincing. And it took doubts out of the discussion.
2. There is a simple explanation why canned cycles are great for old machines: They are short of memory. A canned cycle on my machine needs one line for its definition and can then be reused at different positions with just another line.
3. I can't believe that there are really two inherently different industry standards.
4. When I code the GCodes manually I use rapid moves down to 1mm above the material.
5. I am not familiar with the English notions beyond their usage in FreeCAD, but from this image in the wiki ...
... it seems clear to me that for rapid horizontal moves clearance height is used, and that safe height is used to be safe that the tool hits the material at milling speed. For drilling operations this means that all movements below safe height are vertical moves. I am quite, but not absolutely, sure that no horizontal moves should be made at
safe height either.
6. In sliptonic's video all milling is done in one operation, right? Then there is (currently) no possibility to reduce the height of the horizontal moves, they always have to go all the way up.
7. If we don't want to retract all the way while being in one pocket (and as mentioned above, that's how I would do it manually) then we need two operations. And here we come to an interesting question: How do we get from one pocket to the next at the appropriate height? I see two possibilities:
a) We add another parameter to the job. It would be very appropriate to have there a job-clearance-height, which is above all
clamps and can be used between
b) We add a retract height at the end of an operation. That's perhaps what clearance height was originally designed for.