Fanuc G70 canned cycle
Fanuc G70 canned cycle
(OP)
I am looking for some clues on a problem with a Daewoo 8UHS lathe fitted with a Fanuc OTC-B. Machine works perfectly and is accurate, until canned cycle G70 is called.
If G71(stock removal) is called with 1mm finishing allowance, then part is cut to size + 1mm in diameter and length, which is correct.
If G70 (finishing cycle) is called with 0.5mm finishing allowance, then diameter is to finished size, not to+0.5, and length can be +0.8-1.8.
In summary, G70 does not recognise any U(dia) finishing allowance,always setting it to 0, and always puts in a W(length) finishing allowance, which is random.
Fanuc are working on the problem, but so far no joy. Anybody seen anything like this?
If G71(stock removal) is called with 1mm finishing allowance, then part is cut to size + 1mm in diameter and length, which is correct.
If G70 (finishing cycle) is called with 0.5mm finishing allowance, then diameter is to finished size, not to+0.5, and length can be +0.8-1.8.
In summary, G70 does not recognise any U(dia) finishing allowance,always setting it to 0, and always puts in a W(length) finishing allowance, which is random.
Fanuc are working on the problem, but so far no joy. Anybody seen anything like this?





RE: Fanuc G70 canned cycle
No, but I program an ONA wire EDM machine, and everytime I program a M00 command, all offsets and tapers are lost and remain so for the remainder of the program.
It seems M00 = E-Stop to the ONA engineers. They told me I was pretty much "S.O.L.", so be thankful that at least Fanuc is working on it.
RE: Fanuc G70 canned cycle
Robert Setree
www.advanced-grinding.com
RE: Fanuc G70 canned cycle
RE: Fanuc G70 canned cycle
Make sure you have enough stock on the roughing cycle so that the finish cycle can remove it all.
Especially on tapers and circle moves.
The bigger the tool rad the more stock needed.
RE: Fanuc G70 canned cycle
RE: Fanuc G70 canned cycle
Regards Russel P
RE: Fanuc G70 canned cycle
The point of this post is that I did want to use offsets for this program, in order to fault find the system, and they do not work as described in the Fanuc manual.
There is a fault in this Fanuc system as it does put a variable offset into the Z axis, regardless of whether you program one or not.
The Fanuc manual does describe this method of programming.
Marcus
RE: Fanuc G70 canned cycle
RE: Fanuc G70 canned cycle
RE: Fanuc G70 canned cycle
Bob