Summary of commands when controlling CNC lathes

Summary of commands when controlling CNC lathes
The commands used when the CNC lathe control is used reduces the amount of code to write and gives you more control over complex profiles and operations. An entire machine system will be controlled and operated according to a certain cycle that the programmer has created and ended when the command runs out. With this article, Cosmovina will introduce you to the codes used when controlling a CNC lathe.
Command codes used in CNC lathe control
The first is the G70 Finishing Cycle
G70 PQ;
P = start of profile
Q = end of profile
With this cycle is used for a roughing and follows a certain programming according to that roughing. The P and Q values ​​are used to configure a cycle of operation and the finishing section to be run afterwards.
The second is Rough Turning along the Z axis : G71 Roughing Cycle
G71 UR – G71 PQUWF;
U = Depth of each cutting layer
R = retraction value
P = No. Start profile program
Q = Sequence number to end program profile
U = Residual refinement in the X . direction
W = Residual refining in the Z . direction
F = Feedrate
In the G71 cycle, it is necessary to follow the programmed profile between the N numbers. This cycle is used to remove the longitudinally cut Z-axis materials, leaving the remaining materials for the G70 finishing process.

G72 – Facing Cycle – Rough turning cycle X . axis
G72 W1 R – G72 PQU W2 F;

W1 = Depth per cut
R = retraction value
P = No. Start profile program
Q = Sequence number to end program profile
U = Residual refinement in the X . direction
W2 = Residual refining in the Z . direction
F = Feedrate
With the G72 cycle is also followed the programmed profile of the N numbers. It is also operated like the G71 cycle, but materials are removed along the X axis.

Built-in Pattern Turning Cycle G73 Pattern Pepeating Cycle
G73 U(1) W(1) R;
G73 PQU (2) W (2) F;
U (1) = Depth of each layer cut in the X direction
W (1) = Depth of each layer in the Z . direction
R = Roughing times
P = No. Start profile program
Q = Sequence number to end program profile
U (2) = Residual refining amount in the X . direction
W (2): In the Z-direction, the remaining amount of refining residuals
F = Feedrate
Grooving with G75 Peck Grooving Cycle
G75 XZPQF;
X = Depth of groove (dia)
Z = Width of each groove in the Z . direction
P = Depth per cut
Q = Tool displacement in the Z . direction
F = Feedrate
The cycle is used quite a lot in the industry of screws, nuts, etc.: G76 Screw Thread Cycle
G76 XZIKDAF; G76 P (1) (2) (3) QR;
G76 XZPQRF;
P: display six digits, each with two digits consisting of (1), (2) or (3)
(1) = number of completions
(2) = number of chamfers
(3) = knife tip sheath angle
Q = Minimum depth of cut
R = Value of residual run-through
P = Depth of thread
Q = Depth of head cut
R = Taper
X = Thread foot diameter
Z = It is the position of the end point of the thread
I = Taper
K = Thread height
D = Depth of first cut
A = Thread exit angle
F = Thread pitch
The machine’s parameters are set standard, you can use a block to make the threading process. Note that the G76 threading cycle with 1 command line may not work on all lathes. But the 2-line format of the G76 threading process is more common when programming CNC lathes.
There are still 4 more cycles, G83, G84, G87 and G88, which we will explore together in the next article!
Above are the basic commands to control CNC lathes that programmers use to create short, quality instructions and save a lot of time. Hopefully with this information Cosmo Vietnam has brought you a deeper understanding of the CNC machining industry.