Home Position variation and ATC issue

All info relating to the Denford Triac series of CNC milling machines

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CNC Apprentice
CNC Apprentice
Posts: 74
Joined: Sat 01 Aug , 2015 9:23 am
Hardware/Software: 2001 Cyclone with toolchanger and Fanuc 21i control
Serial number - H00913.
Voltage 415V F.L.C 20A 50Hz 3Ph

1997 Triac VMCwith toolchanger and Fanuc O-M control
Serial number - 70826B.
Voltage 415V F.L.C 30A 50Hz 3Ph

Home Position variation and ATC issue

Post by jamesgates1000 » Sat 06 Jul , 2019 8:02 am


I am having a couple of issues with my Triac and was wondering if anyone can help...
These problems used to happen once every few months but now have become more regular.,
Haven't used it for a few weeks but need to use it on some jobs soon so need to try and sort these problems.

Firstly the tool change keeps erroring out intermittently, the carousel moves into position, head rises then this error appears...
20190705_121716.jpg (145.28 KiB) Viewed 79 times
The second problem is that the Y axis home position keeps changing by 2.5mm, I home the machine, set the datum, then at some point when it homes either when the machine is turned on or even between tool changes the home position is offset by 2.5mm which offsets datum and unless I watch it scraps the job.

I guess that it is probably a home switch problem, I have a Fanuc OM Triac and it has 3 limit switches on the Y axis, I have recently replaced the back one and the middle one. I was under the impression that the one right at the front was a travel hard limit and was not involved in the homing sequence. Anyone know?

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Re: Home Position variation and ATC issue

Post by Martin » Mon 08 Jul , 2019 7:38 am

It may be worth doing manual M codes to see where its failing.

M20 - Arm Out
M21 - Arm In
M22 - Arm Down
M23 - Arm Up.
M24 - Drawbar Uncloamp
M25 - Brawbar Clamped
M32 - Carousel Clockwise
M33 - Carousel Counter Clockwise
M34 - Carousel Half Pocket
M27 - Reset to Position One.

With the homing error you may need to adjust the home switch. It may be too close to the zero pulse on the motor.

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