4 Axis Toolpath Worked Before - Toolpath now fails to execute on HAAS with NGC

[kepp.andrews]

Posted in Both Support and Manufacturing Forum (admin please delete from incorrect forum)

I previously used 4th axis rotary toolpaths and it works great. Today I tried to use a very simple rotary toolpath that cuts in either spiral or circular mode, but it is now failing.

In The Fusion 360 Workspace:
- The simulation looks good and correct.
- The .NC file is written with no errors or warnings.
- In Post Properties, Optional Stop is not checked.

At The HAAS Mill: 

- X & Y coordinates are read and the movements are correct. 
- Z axis moves down to the part and then stops above the part before beginning the cutting toolpath. 
- The rotary turns. 
- The spindle turns. 
- The actual cutting toolpath fails to start. The spindle stops above the part. 
- There is no alarm.

My errors with Fusion 360 have mostly been self-inflicted. I expect this to be the same, but any guidance is much apprciated.

[johnptc314159]

please post model 🙂

[kepp.andrews]

f3d file uploaded

[johnptc314159]

when i look at your  nc program i dont see any negative z axis moves...   yours is 9999   when i posted it as 1001   the z behavior is very different.  post haas ngc with 4th axis enabled...

[seth.madore · Accepted solution]

Yeah, it's going to Z.1859 to Z.1860 pretty consistently across the part 🤔

@kepp.andrews I assume that you have in fact set your WCS Z zero (at the machine) to the center of rotation and not the top of the part?

[kepp.andrews]

John thanks. I can figure out what's wrong with that info. I thought my rotary was enabled, but me double check. I'll post again after checking.

[kepp.andrews]

Is this what you wanted for a model or is it another type of file?

[kepp.andrews]

dwg file uploaded

[kepp.andrews]

(3) PNG files attached

Post Processor - one pic

Post Properties - two pics

[kepp.andrews]

WCS is set to center of rotation. See Pic

[kepp.andrews]

It's obvious, after seeing Johns reply, that  his .NC file and mine are very different, but I'm not sure why. The toolpath is very simple. It just moves along the length of a rod that is rotating on the X axis. Once the Y and Z coordinates are reached the only real movement is along the X axis. This is how my post looks. Z and Y axes moves should be very minimal. Just not sure why now, the Z axis is stopping above the part instead of engaging and moving along the X axis.

To be clear I'm reducing a .375 diameter rod by .0015 which gives me a finished diameter of .372 rod. Doing this exact same thing previously gave me an acceptable finish with less time sanding or buffing.

It is also interesting that NCViewer simulation shows a good toolpath on my .NC file just as Fusion does.

[kepp.andrews]

John, [Post Properties] [Has A-axis rotary] is selected with either Yes or Reversed. Both yield the same result as before.

[kepp.andrews]

I was comparing the two files (yours and mine) and I don't understand why yours has so many Y Axis moves.

The part is simply a rod that is going to have the diameter reduced by .0015

Y Axis moves are only used to get the end mill centered above the rod which rotates on X axis.

Once the end mill is above the correct Y axis it will go down (neg) in the Z axis then travel X axis until finished.

Still unsure what's happening, but will continue to search.

[kepp.andrews]

Stupid-User-Tricks

 

I haven't ran this setup in several months. Forgot to add back the radius after Z height probing.
I'll buy the book and try to stop asking stupid questions.

[seth.madore]

Ha, if I had a dollar for every stupid thing I've done in the last 24 years of machining...