Hi, I have a green screen Okuma LB15 that has started cutting the incorrect thread pitch.
The control is the OSP5000L & I have cut many threads, both imperial & metric without issue until the other day.
I ran a 2mm pitch & over 20 threads it is about 0.7mm out of wack & when I tried a 12TPI it is closer to 13TPI
I have been using
S400
G71X25.26Z-50H2.44D.3U.07F2M22M33M74
G71X--Z--H---D.3U.07F25.4J12M22M33M74
but have tried G33 & just using a feed of 2mm, all with the same results.
The tool tracks or chases the thread spot on each pass, but the pitch is wrong. Also, the pitch appears to be progressively consistent in error
So far I have checked the backlash on Z axis (less than 0.005mm)
Programed spindle speed verse actual speed (checked with digital tacho)& got:
Programed speed 500 RPM - actual 493.3
1000 RPM - actual 992
1500 RPM - actual 1489
2000 RPM - actual 1987
Any help would be much appreciated.
Regards ozbob
The control is the OSP5000L & I have cut many threads, both imperial & metric without issue until the other day.
I ran a 2mm pitch & over 20 threads it is about 0.7mm out of wack & when I tried a 12TPI it is closer to 13TPI
I have been using
S400
G71X25.26Z-50H2.44D.3U.07F2M22M33M74
G71X--Z--H---D.3U.07F25.4J12M22M33M74
but have tried G33 & just using a feed of 2mm, all with the same results.
The tool tracks or chases the thread spot on each pass, but the pitch is wrong. Also, the pitch appears to be progressively consistent in error
So far I have checked the backlash on Z axis (less than 0.005mm)
Programed spindle speed verse actual speed (checked with digital tacho)& got:
Programed speed 500 RPM - actual 493.3
1000 RPM - actual 992
1500 RPM - actual 1489
2000 RPM - actual 1987
Any help would be much appreciated.
Regards ozbob