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explaining how to use the c axis on a CNC lathe machine???

Dear Friend,

'C' axis can be used for various applications : viz. Axial cam cutting, Key way generation, PCD holes on the face / periphery, drilling, tapping, end milling, what is the application for which you require guidence ?

basically any help on the C-axis i can use, but specifically i need help on cutting a internal helix inside a 1/2" diameter hole, with a depth of .010" and a width of .147" through a piece about 6" long.

You will have difficulty in accommodating live tool inside 1/2" dia. You better choose a 2 axis method as explained below :

First make a form tool for internal square threading of whatever width and depth that you want. Then use either G92 or G76 cycle to generate the helix. It is not that complicated ! you will have to specify the pitch as per the helix angle required.

regards,

Jasmin shah

Can you explain what internal square threading means or what are the differences between G76 and G92??? Also the "pitch" for the helix is one complete rotation in 8 inches, so how do i compute the helix angle for that.

unless I see the drawing of the piece, I can't precisely comment on it. Can you attach PDF drg. with the message ? May be Ivanirons can help us in this regard.
You can very well imagine that I am simulating your helix generation with a standard internal thread cutting. G92 and G76 are the corresponding thread cutting cycles (in FANUC). Feed in these cycles will have to be specified as equal to 8". Pl. refer to FANUC Programming Manual for the syntex of these cycles.


Jasmin shah

Unfortunately i don't have a picture that i can post here. can you used G76 or G33 to cut a helix with a pitch of 1 full rotation in 8", or would polar coordinates need to be used??? and do you have any ideas about what kind of tool would i need to cut the groove in the 1/2" hole???

Sorry i dont work in inches so i converted it to mm.
G21 ( input in mm )
G0 X12.7 Z5.0
G76 P040000 Q0.02 R0.02;
G76 X13.208 Z-160.0 P0254 Q0127 F203.2;
G80;
(this is a large pitch and trial and error on speed advised)
eg. G97 S100 m0? ( left hand or right hand? )
Ignore usual speeds and feeds recommended.
What material are you using?
How many in a batch are you manufacturing?

how did you compute the F value??? And the helix is right handed, the material is steel, i am just planning on making one.

BTW can you explaim what the G-codes mean and what they are doing it the code you wrote for example:

"G0 X12.7 Z5.0

G76 P040000 Q0.02 R0.02;

G76 X13.208 Z-160.0 P0254 Q0127 F203.2;

G80;"

Can you explain what the machine is doing in this sequence??? Thanks.

how did you compute the F value??? And the helix is right handed, the material is steel, i am just planning on making one.

BTW can you explaim what the G-codes mean and what they are doing it the code you wrote for example:

"G0 X12.7 Z5.0

G76 P040000 Q0.02 R0.02;

G76 X13.208 Z-160.0 P0254 Q0127 F203.2;

G80;"

Can you explain what the machine is doing in this sequence??? Thanks.