5 axis post question

[GREG]

hello all

Im currantly trialing a 5 axis post from our dealer for a mazak Vortex with fanuc control.

My question is why would I need to input tool length when posting.The post has an option not to but tool paths at the machine are differant.

I'm wondering if this is a machine option or parameter.

Its a second hand machine so not much help from machine supplier available.

Any enlightenment would be much appreciated.

 

Cheers

[crazy^millman]

Well let me see if I can explain this in a way that makes some sense to you. Any 5 axis Machine has what they call a poivit distance. This point the the place where the machine truns the head from. Now here is the trick with the post and the machine. You either will have a controller that uses a tooleye or some other way by toughing of to a fixed point with the head vertical to get a length for tool in the spindle and every other tool. Depednign on this means alot to how you go about apporaching programming the paths. If the machine has a 12" poivit and automatically adjusts the machine for any difference in what the tool actually is then you would have to just have the post defualt with the 12" amount and your parts would come out perfect. Now if you have a machine that does not and you need to adjust the post to each tool length for the poivit distance for each one. The best way I can explain it is if you have a head that could go 90 to the left and the povit distance from the poivit point to the end of the tool is 12" then the x axis would have to move over 12" if the face you were maching is a X0. So on most machines it does not make a hill of beans for 3axis machine to know what the povit distance is if all the tools are touched off to the same point but in 5 axis or 3+2 milling that is where it is of the utmost importance to know what the poivit distance is and know it accurattly.

 

 

IHTH

[Steve Biehl - Cimquest Inc]

Some of the newer Fanuc's have G-codes to comp the tool in 3D space. You then do not need the tool length to post, the machine takes care of the calculations that Ron is talking about.

 

Hiedenhain TNC/Millplus controls have been doing this for a while.

[Allan Brown]

See if your control has a G43.1 function for 5-Axis tool length comp based on the current H register loaded.