Why is G81 doing this?

[Rico55]

I'm running a router with Mach3, and when I program a file to do a drilling routine with G81, it does a pecking movement, and repeats the drilling move twice in each hole. I have looked everywhere for a setting in Mach3, but am not seeing something that controls G81 routines- can anyone explain this to me?
Thank you in advance.

[mactec54]

Rico55

You will have to post the G code that this was happening with, save it as text & you can post it here

[ger21]

Check the manual, you might need to call a G99.

[Rico55]

Here's a snippet of code, which is just repeated for the other hole locations.

N1G90G70G40
N2 ;MOP NAME: Standard Drill
N4T2M6
N5G97 S10000M3
N6G0X5.3817Y8.5781
N7Z2.
N8G81R0.6Z-0.05F30.0M3
X5.3817Y8.5781
N9G80

Ger,
Maybe you could explain to me, a little more clearly than the manual, what the R value does, and what a G99 command would do.

Thank you.

[mactec54]

Rico55

N1G90G70G40
N2 ;MOP NAME: Standard Drill
N4T2M6
N5S10000M3
N6G90G0X5.3817Y8.5781
N7G43Z2.H2
N8G81G99Z-0.05R.1F30.0
X5.3817Y8.5781
N9G80

A G99 moves the Drill up to the set R Value

I like to use a G98 were the G99 is, this will move the Z axes up before the next move to what ever the Z is set at,( You Have 2.), But because you have your retract at .6 which is a large peck, this will clear your work most likely

When using a G98 you can set the R value to 0 so the drill will (Peck)to the top of the part only & save a lot of Peck movement, The G98 when the hole is finished will move the Z up to your Z2. number & move to the next hole

Try it both ways to see what you like best, try the code above this is what it should look like