I have been making a lot of items lately that will be hung up, so I wanted an easier way to cut keyhole slots.
I created a ‘Quick Action’ to do all the work for me. I just load the bit, set Z Zero to top of stock, and the keyhole is cut centered on the current X-Y - no need to zero X-Y. I found that comments work, so I included them in the code.
I’m using a keyhole bit like this:
https://www.leevalley.com/en-ca/shop/tools/power-tool-accessories/router-bits/30113-keyhole-router-bits?item=16J7001
I found that cutting 7mm deep seems to work well.
The Action cuts a 50mm horizontal slot, centered on the current X-Y. When finished, it returns to the starting X-Y, and retracts on Z.
Quick Action:
Name: 50mm Keyhole Slot
Description: Cut a 50mm horizontal keyhole centered on the current location.
GCode:
G21 (Metric)
G90 (Absolute)
G0 Z10 (Move to 10mm above surface)
G91 (Incremental)
G0 X-25 (Move left to start of keyhole)
G0 Z-9 (Move to 1mm Above Surface)
M03 S18000 (Turn on spindle)
G1 F200 Z-1 (Drop to Z0)
G1 Z-3 (Drop Z-3 mm)
G0 Z4 (Retract to Z+1)
G1 Z-7 (Drop to Z-6)
G0 Z7 (Retract to Z+1))
G1 Z-8 (Drop to Z-7)
G0 Z8 (Retract to Z+1)
G1 Z-7.9 (Drop to bottom of entry hole)
G1 F300 X50 (Travel 50 MM right)
F600 X-50 (Back to Entry)
G0 Z7.9 (Back to Z1)
M05 (Spindle off)
G53 G0 Z-10 (Retract)
X25 (Return to start)