5 Axis question

[mman10]

Calling all 5 axis gurus. Can somebody explain dynamic compensation to me? Is that what makes the difference between a true 5 axis machine and say maybe a 3 + 2 axis? I have been told that some machines require you to repost each time you probe a part, we run 2 shifts here and sometimes need to take our parts out for 2nd shift. We have Hermles now, but I have never really heard of this. Thanks.

[crazy^millman]

Do a search this has been covered quit well in the past. Only reason you would to repost is if you are using gage lengths for tools and that changes. Dynamic give you the ability to use a set length and then the machine will adjust based off of any difference from changing tools without the program having to be reposted.

 

HTH

[Christian Raebild]

Basically, dynamic comp. means the control takes the tool length and the part position relative to the rotary axes into account when moving the rotary axes, and so does the tilted plane function. The end result is that you do not need to know that information when posting, and the post processed program can be reused even if the tool lengths and the part position relative to the rotary axes changes.

 

Hermles often have Heidenhain TNC controls, and they support dynamic compensation. On the Heidenhain TNC control (using Heidenhain conversational format) the dynamic comp. is activated with M128 and deactivated by M129, and for tilted plane machining (3+2 axis) you would use either Cycle 19 or (on iTNC 530 controls) PLANE SPATIAL. Of course, your post processor would have to support those functions, too

 

Millplus and Siemens 840D controls have similar functions, unless they are rather old controls.

[Josh T™]

Christian nailed it.

 

If your machine has a Heidenhain control and your post is setup to output the PLANE SPATIALs (CYCLE 19s) and the M128 you're all set. You could probably setup the program to L call a probing routine at the beginning of the program to probe every part that runs. This would remove any doubt that your parts are datumed correctly.

HTH

Josh

[mman10]

Thanks guys! Shortly after my post I did the search and found the info needed, Chritian you put it very plain and easier to understand (now I can explain to my Supervisor).