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Setting up a CNC lathe – FANUC G50

In (c)NC, G-Code, Setup, Start Here by Micah HoffmannLeave a Comment

Note: The G-code and procedures assume Fanuc controller, but concepts can be used across brands. “Making The Connection” There are three important relationships you need to make when setting a CNC lathe. Machine Zero or Reference Point. Tool Change Position/Safe move (G50) Program Zero 1 and 2 are the XZ location of the center of the tool turret. Setting Tool Length Offsets using Q-setter (Note: If you need to know the manual version of this process, let me know) For the love of sweet baby whoever, if you don’t already have a Q-setter automated tool offset system… go get your …

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Lathe Speed Control – G96 Constant Surface Speed

In G-Code by Micah HoffmannLeave a Comment

The lathe as we know, is different than a mill in the simple fact that with a lathe, our part is what rotates and our tool is what stays steady. Because of that we need to calculate our speed and feeds based of the rotation of the part. Cutting Speed (SFPM) = (Spindle RPM X Cut Diameter (in.)) / 4 Like a mill we could use a G97 and set a constant speed of 500 and make our cut.  But, what if we are preforming a cut that reduces the Cut Diameter parameter from above.  (Think basic facing operation) So we know …

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Goodbye Tape, Hello MCU

In History by Micah HoffmannLeave a Comment

I mean this when I say it, thank you to all of the engineers that came before me, who’s main goal it was to eliminate the need for us to use punch tape code… Enter > MCU (Machine Control Unit) A CNC machine is just an NC machine, yes it has the added benefit of an attached computer. When your favorite machine supplier builds your future CNC machine, they pre-load the MCU’s ROM (Read only memory) with their own software. This will control executive functions that will not be erased when the machine is powered down. ONe of the major …

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An Example G-Code program (Drill four holes)

In G-Code by Micah HoffmannLeave a Comment

G90 G20 G40 G80 G91 G28 X0.0 Y0.0 Z0.0 G92 X-10.0 Y5.0 Z0.0 T1 M6 G0 G90 X.5 Y-.375 Z0.0 S1600 M3 G43 Z.1 H1 M8 G83 X.5 Y-.375 Z-.45 R.1 Q.1 F5.0 X4.5 Y-1.625 X.5 G80 G0 G90 Z4.0 M5 M9 G28 X0.0 Y0.0 Z0.0 M30 G-Code Meaning O01334 Program Number (X0Y0 IS THE UPPER LEFT HAND CORNER, WHEN LOOKING AT THE MACHINE/PART) (X0Y0 IS THE UPPER LEFT HAND CORNER, WHEN LOOKING AT THE MACHINE/PART) (Z0 IS THE TOP OF THE PART)(TOOL1: 1/4 DRILL) Detailed Comments should ALWAYS be added to the top of your program, and throughout. G90 …

Machinist Job Set Up (Making The Connection)

In Setup by Micah HoffmannLeave a Comment

Machine Home and Part Origin The machine home position is a physical location of the machine that is set by the manufacturer. Each machine will have a “work envelop” which should be maximized with the proper machine home. The part origin will ultimately be a Cartesian offset from the Machine 0,0,0. (See pic1) If datum’s are specified on the blueprint, the part origin must be the intersection of those three planes. If GD&T is not in use, then the Machinist should consider where the majority of the dimensions are coming from. Find the Edge The standard edge finder will have …