Yet another robodrill problem - Distance to go .0001 on milling profile?

So, I don't know if this is another symptom of the problem I had in my last thread, so starting another.

The other being stuttering toolpaths when not using g5.1 on our 1997 t14ia robodrill. Thread here: www.practicalmachinist.com/vb/cnc-machining/16i-ma-robodrill-high-speed-milling-choppy-slow-337540/

Anyway, we finished the job in the thread above (didn't solve it but using g5.1 worked) and I'm now setting up another job on the same machine.


This is a rounded cam milled off center of a pin. So holding 2 parts at a time in vertical V jaws, using g57 and g58 for the cam profile.

1/2 endmill.


Anyway, the program has the same program copied and pasted 2 times, and we are using volumill to rough, and just a couple simple g2 commands to finish profile after roughing. We have been running this every year since 2011 using the same program. Always until now on various 1990s leadwell vmcs with 0m controls.

Now, I put in g5.1 on this because I didn't want it to be choppy. And it fully completed the roughing and finish cycle on g57. Then it went to g58, completely finished the roughing cycle, but on the last line of it, it stopped and shows "distance to go" as .0001 in Y.


WHY?





As you can see, it made it to where it was programmed to go (see "absolute position").

It has never given an error on any machine before.

Any ideas? Looking for parameters I need to adjust. I should not need to adjust my program, I tested this toolpath in our 16i-mb makino and it also has no problem doing this. only this robodrill.

hy maybe you hit the case of inacurate code from cam + control tolerances on radius

at some machines, it is possible to set the control tolerance when machining a radius

also, even if this is possible or not, is good to know that program coordinates wont require tolerance behaviour from the control

one way to do this may be replacing IJ with R ... this is all i can tell kindly !

As an update, I ran the code 2 times early saturday, it gave the same error. And then I ran it one more time, and it processed the whole program without issue.

We are currently running the machine and its done a dozen cycles without stopping at that point. And I did -nothing- to change it. It simply started working.


???

pls post the code arround the line/adress where you have errors ...

2 lines before and 2 lines after ? or you know, a paragraph from it, that shoud be sugestive ?

hello as i can see, your issue is always in same place; consider trying :
... a lower feed on your last feed movement
...... or
... ad an extensions line to your toolpath, with a normal length and normal feed, than can be accurately executed by your cnc ( 1200rot/min x 0.1mm/rot among a segment length of 10mm should deliver;1200*0.1=120mm/min, while you run at F50*25.4=1270mm/min )
...... or
... ad an extensions line to your toolpath, with a short length, thus to succumb the cnc, so to force it to reduce feed

thus, my only guess, is that you may be machining at a too high feed

No. Just no.

dandrummerman21 said:

No. Just no.

Click to expand...

Gary