[DeWaltMFG]

Im trying to do a circular interpolation using BOBCAD v30 and im running a Fanuc 21m control. Im using the fanuc 21m post processor and when i post it there is no Z movement in the interpolation line (G03) so the machine just hovers above the part doing circles. If i add a Z movement, either with a different post processor or manually, the machine errors out as soon as it sees the Z movement and says "illegal plane movement commanded." Any tips?

[The Engine Guy]

If my memory is serving me right then I think that Helical Interpolation is an Option on your control, that will mean that the Parameter to enable it will be one of the 9000 Parameters, I think it is Parameter 9930 Bit 3 that needs to be changed, usually costs money for Fanuc to do it
That would look something like 9930 00001000. Parameters count from the right and begin with 0 not 1 so Bit 8 from the right is actually numbered 7, hope that helps

Sorry, that`s all I`ve got

P.S. Just found this, have a look here for yourself

https://www.scribd.com/doc/273845264...Parameter-9900

Regards
Rob

[aldepoalo]

DeWalt MFG, it should be a simple fix to your post. Not all machines support helical motion which is why it's not defaulted on.


This video should help you understand how to edit a post.

https://youtu.be/fyyViHren4I

What you are looking to do it edit the post format for arc moves.

The 64 block should look like this:


64. Arc move XY
n,g_arc_plane,g_arc_move,x_f,y_f,z_f,arc_center,fe ed_rate


This format gives you this g-code:


N10 G17 G03 X-1.735 Y0. Z-0.05 R1.735
N11 G03 X1.735 Y0. Z-0.1 R1.735
N12 G03 X-1.735 Y0. Z-0.15 R1.735
N13 G03 X1.735 Y0. Z-0.2 R1.735
N14 G03 X-1.735 Y0. Z-0.25 R1.735
N15 G03 X1.735 Y0. Z-0.3 R1.735
N16 G03 X-1.735 Y0. Z-0.35 R1.735
N17 G03 X1.735 Y0. Z-0.4 R1.735
N18 G03 X-1.735 Y0. Z-0.45 R1.735
N19 G03 X1.735 Y0. Z-0.5 R1.735
N20 G03 X-1.735 Y0. R1.735 F89.2592
N21 G03 X1.735 Y0. R1.735

[DeWaltMFG]

Thanks fellas! Sorry it took so long to reply. I dont think the machine supports it, like Rob mentioned. I was able to contact Bobcad and have the post processor modified to add the Z movement, but i get the same "illegal plane" error. More confused as to why my Grandfather(boss) assured me the machine supported helical interpolation. Guess its time to push for an upgrade.
Thanks!
Joshua

[The Engine Guy]

Did you check the Parameters to see if it is enabled ??

Regards
Rob