[axis overtravel]

this problem is simple. the solution may not be...

one of our 4020's has a pallet changer. i have coded
a program to probe 4 parts on pallet A, continue machining, then change to pallet B

when using the fitted Renishaw MP12 probe to update work offsets, which, by the way is sucessful, the subsequent pallet changing routine fails, with the A pallet hitting the Y axis limit switch in the + direction

this does not happen 100% of the time, but about nine times out of ten, the machine will hit the limit, the tenth time, the pallet changer will function properly.

when the probe cycle is omitted, and with programs that do not use probing, the pallet changer works fine all the time.

i have ensured that all tool and fixture offsets have been cancelled before programming the pallet change.

i have also called Renishaw's tech support. they have not encountered this before, and are at a loss as to know what the cause may be. i have calibrated the probe using Renishaws' procedure, and i have verified that the work offsets are being updated. i have since emailed Fadal's support staff, and am waiting to see if they respond.

has anyone else ever experienced this problem?

[bradleync]

axis_overtavel,

Do any of your subs use this command?

N3245 G0 G90 G49 Z0
N3246 E0 X0 Y0
N3247 #START 7 This calls a jump to program O7
WAIT
This command temporarily pauses processing of the program lines at the line
with the WAIT command. Processing will continue when the execution buffer is
completely exhausted. The WAIT command is also used to have the machine absolutely stationary before printing out the current location of the machine using the axis variables.

(This is taken out of the Fadal manual)
I am referring to the:

"WAIT" Command is often forgotten, but on a Fadal is a requirment for stable performance.

[axis overtravel]

thanks for the reply

i tried the WAIT command, but to no avail.

the best i have managed to achieve, is altering the place where the alarm occurs. the uk fadal agents have as yet not been able to deduce what the problem is...