[BID-000005] Drill operation

@takshak-forum-botTakshak Staff14 Sept 2026

Using AFR, holes detected. When i use drill, feed rate can not be adjusted in the feedrates box. Everything but plunge is greyed out.
When generate G-code, machine flags Feed mode G94(u/min) should be G94(mm/min).
Selecting canned drill cycles, but the tool path is fully programmed, using LinuxCNC post.

Submitted via the support form by @hephaestus on 2026-09-14 22:39 UTC. Reference BID-000005.
Replies here are public. The submitter is answered by email.

Replies (1)

trackwhackTakshak Staff15 Sept 2026(edited)

Thanks for the detailed report. Three separate things, in order.

Feed rates on a Drill op. That is intended. A drill only moves the cutter straight down, so the plunge feed is the only cutting feed it has; retracts run at rapid. The other feed fields are greyed because no move in a drill op would use them. Ops that cut sideways (pocket, contour, bore) have them live.

"G94 (u/min)". That text is Takshak's own export dialog, the locked header line showing what the file starts with, not something the machine reports. The "u" is short for units: G94 means feed per minute in whatever unit the program is in, and the row above it sets G21 (mm), so the machine reads every F word as mm/min. The file itself contains G21 and G94, which is exactly what LinuxCNC expects. [Agreed it reads badly; the next update spells it out.]

Canned cycles posting as long-hand. The checkbox asks for a cycle, and the post uses one whenever it reproduces the programmed motion exactly. When it cannot, it writes the moves out, so what runs on the machine is exactly what you saw in the preview. The cases that fall back:
- a peck depth that splits the hole into exactly two strokes (peck at half the depth or more): a cycle's single Q word cannot express that pattern faithfully, so the moves are written out; with three or more strokes you get G83 (or G73 with partial retract);
- peck and dwell together: LinuxCNC refuses Q and P on the same block, so those holes are written out with a G4 at each bottom;
- a plain hole with no peck posts as G81, dwell only as G82.

If your drill op had a peck depth set, that is most likely the reason. If you can send the drill op settings (hole depth, peck depth, dwell) or the .ngc file, I will confirm which rule applied. [We are also looking at lifting the two-stroke case.]

Overall Takeaway - The units/min will be modified to mm/min or inch/min in an upcoming enhancement (possibly the next one scheduled on 15th September)