No Feed Error on Fanuc 18i

[Mick]

Hi there,

I'm doing a test toolpath on a Fanuc 18i C axis lathe. The post has out code as follows, and when it encounters the F.9 error, it returns "No Feed Commanded"

X60.62 C32.879 F740.3
X62.509 C35.52 F697.3
X64.545 C38.028 F654.9
X66.722 C40.405 F613.5
X69.036 C42.654 F573.6
X70.334 C43.811 F544.1
X71.66 C44.927 F524.2
X68.036 C44.924 F.9
X64.848 C44.92
X61.66 C44.915
X60.878 C44.857 F67.
X60.115 C44.68 F202.3
X59.393 C44.387 F336.7
X58.73 C43.98 F466.8
X58.145 C43.467 F588.4
X55.887 C40.966 F669.8
X53.771 C38.297 F724.3
X51.805 C35.453 F781.4
X49.998 C32.431 F840.4
X48.357 C29.228 F900.3
X46.891 C25.848 F960.
X45.61 C22.295 F1017.9
X44.521 C18.583 F1072.2
X43.634 C14.728 F1120.8
X42.955 C10.755 F1161.7
X42.489 C6.692 F1193.
X42.243 C2.572 F1213.2

I'm assuming that the post has output the F.9, and the machine is interpreting the feed as too low, and hence the error. Is there a minimum mill feed in the post somewhere that I am missing (I can't find one).

The post outputs the correct feedrate units command (G98)

[Leon82]

could the two lines without feedrates are the issue?

if you run it in single block it should stop on the actual error. when single block is off it will read a few lines ahead and get the alarm before it would actually occur

[Mick]

17 minutes ago, Leon82 said:

could the two lines without feedrates are the issue?

if you run it in single block it should stop on the actual error. when single block is off it will read a few lines ahead and get the alarm before it would actually occur

Feedrates are modal, so no, it shouldn't matter. But, I will get them to check in the morning

[Prodoggg]

In G93 (inverse time feed) there must be an F (feedrate) command on every line. The control calculates the length of the axis move and the time specified with the F command on every line. The feedrate is only modal in G94 (feed per minute) or G95 (feed per rev) modes. Hope this helps.

[Mick]

3 hours ago, Prodoggg said:

In G93 (inverse time feed) there must be an F (feedrate) command on every line. The control calculates the length of the axis move and the time specified with the F command on every line. The feedrate is only modal in G94 (feed per minute) or G95 (feed per rev) modes. Hope this helps.

Thanks for the reply. This is a Fanuc controlled C axis lathe, so there is no inverse time feed option. I'm suspecting it is some kind of minimum feedrate error.

[gcode]

Have you tried changing that F.9 to F1.

and adding it to the 2 lines that don't have a feedrate

[civiceg]

Quote

In G93 (inverse time feed) there must be an F (feedrate) command on every line. The control calculates the length of the axis move and the time specified with the F command on every line. The feedrate is only modal in G94 (feed per minute) or G95 (feed per rev) modes. Hope this helps.

There is a parameter that can be changed on a FANUC. This way you do not need to have a duplicate feed, when the change in distance is the same. 

[Mike@Lustre]

We  have 2 18i controllers with C axis use , we use a G87/G88 and have used a .005" feed rate when drilling . I don,.t see why you could not use that slow of a feed rate for milling .

[nickbe10]

Does the control require a leading zero?