G73 Peck Drilling Example (Canned Cycle)

G73 Peck Drilling Example

G73 is a peck drilling canned cycle.

This cycle drills holes and breaks up the chips as it goes. It does not fully retract from the hole.

It retracts just enough to break the chips up.

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 (G73 Peck Drilling Example)

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 G73 Cycle instructs it to drill a hole 17.5mm deep (Z-17.5) at a feed of 200mm per minute (F200.)

The Q2. tells the machine to drill the hole in 2mm steps. After each step it retracts a small amount to break up the chips from the drilling.

As it drills the depth increases by 2mm each time.

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.)

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 (G73 Peck Drilling Example)

G73 Drilling Example

If you have been affected by any of the issues in this post or need CNC Counselling then contact me.

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