No Work offset

[Jelle_b_k]

Hi all.

I recently received an old Matsuura MC-1000V, that I’m suppose to set up.
The machine has an old Fanuc 6M control system, but apparently the system don’t have any work offset option.

So my question is, which way will you recommend me to set my work offset?
What I’m thinking is to, of course return the machine to its zero return at start up, and then set a work coordinate in the beginning of all my programs. But I don’t like the idea of using G92, as I consider this very dangerous and very inconvenient if I have to restart my program from a different point than the start.

Is there a different G code, which will always set the coordinate system from the machine origin point, and not “add” the value every time you program it?
In this way I could set the work zero coordinate after every tool change, to avoid any mistakes.

Any suggestion is highly appreciated!
Thanks.

[Maxter]

If your Fanuc has Macro B you can use an infinite number of 'fixture' offsets. There is a safe way to use G92 where you need not move to a particular spot prior to setting G92. This can be accomplished mathematically using system variables. Since I'm an Okuma man I don't have the Fanuc syntax at my fingertips... Basically you use variables instead of fixture offsets with code that goes something like this:

G92 X= actual position - origin of machine coordinate system - X variable value, Y= actual position - origin of machine coordinate system - Y variable value.

Your X & Y variable values would change for different 'fixture offsets'. Check the Okuma forum this weekend... I'll find and upload an Okuma sample program that uses G92 to do a Family of Parts via 'G92 grid code'. This is what I use on Gang Fixtures in my shop.