[pickled]

As stated by many others here- purchase what you will use. If your CAM package doesn't support 4th axis work, or if you have never used a 4th axis before, you might want to re-think the purchase. I have two 4th's and zero PDB's or tool changers on my machines. Manual tool changes are pretty simple for me especially when you throw the Tormach supplied wrench into the scrap bin and use a purposely built tool that provides proper leverage. Belt position changes are more of a PITA for me here mainly because you have to remember to perform the change within the software as well. If I could go back to the beginning and do it all over again I would have spent less on Tormach accessory hardware in the beginning and invested more heavily in fixture sub-components, quality indicators and specialty cutters (insert tooling, thread mills, slitting saw arbor, corner rounding end mills...etc).

[mountaindew]

As stated by many others here- purchase what you will use. If your CAM package doesn't support 4th axis work, or if you have never used a 4th axis before, you might want to re-think the purchase. I have two 4th's and zero PDB's or tool changers on my machines. Manual tool changes are pretty simple for me especially when you throw the Tormach supplied wrench into the scrap bin and use a purposely built tool that provides proper leverage. Belt position changes are more of a PITA for me here mainly because you have to remember to perform the change within the software as well. If I could go back to the beginning and do it all over again I would have spent less on Tormach accessory hardware in the beginning and invested more heavily in fixture sub-components, quality indicators and specialty cutters (insert tooling, thread mills, slitting saw arbor, corner rounding end mills...etc).

Well said!
A pdb was absolutely required in my case and I would not have purchased mill without this option. I also found things like tts height measurement system, hamier probe and fog buster were also required to help improve work flow, cleanup and overall experience.
On the other hand I have also invested a small fortune in measuring tools, fixtures, indicators .... all the stuff you need to hold onto and or interface with the world and make chips out of. And still need to spend another small fortune to get up to full speed. I want a sb15 lathe but pretty much put that on hold until I get a decent tool box for mill setup with decent quality tools. Then I can add machines for all these tools .
fun stuff

[philbur]

As stated by many others here- purchase what you will use. If your CAM package doesn't support 4th axis work, or if you have never used a 4th axis before, you might want to re-think the purchase..

You don't need four axis CAM in order to make good use of a 4th axis. For example this clock fusee, which was hand coded with a bit of help from Excel. It's a 2.1 mm pitch variable diameter helix. It was surprisingly easy to code. Also of course a 4th axis is very useful for cutting gears, splines and such like.

Attachment 278130

Phil

[pickled]

That is a lovely piece of work! Yes, a 4th axis is useful for such jobs and I agree that one can program by using discrete variables in a spread sheet when needed. If one is going to use the 4th axis for extensive 3D surfacing and producing features of discontinuous geometry CAM would most likely be the viable way to efficiently generate G-code.