G81 Drilling Example (Canned Cycle)

G81 Drilling Example

The G81 is the most commonly used canned cycle it simply drills a hole and retracts.

All other canned cycles are similar to this but with a few extra bells and whistles.

G81 Drilling Example this simple part has four M12 holes drilled countersunk and tapped.

The datum is the centre of the part so the holes positions are.

X55. Y55.
X-55. Y55.
X-55. Y-55.
X55. Y-55.

Here is the CNC code

The machine first moves to X-55. Y-55. and rapids the Z axis to 3mm above the part.

It then rapids the Z axis down to 1mm above the part R1.

The G81 Cycle instructs it to drill a hole 6mm deep (Z-6.) at a feed of 200mm per minute (F200.)

When the hole is done it rapids back to the initial point (Z3.) This was in the line

This is because of the G98.

If it were G99 it would return to 1mm above the job (R1.)

See explanation of G98 and G99

Once the cycle is active each time it sees a position it repeats the drilling process.

When the G80 is programmed it no longer drills holes.

Now watch the video to see it all in action (G81 Drilling Example)

Haas G81

See full explanation

Thanks

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