Fanuc OM-C home position

[Stebedeff]

Hi guys,

We have a Kitamura Mycenter4 with Fanuc OM-C. I have just renewed all the bearings of the z-axis spindle as they were wornout. Now the homeposition of the z-axis is too high so that the ATC swingarm is to low for toolchange. How can I lower the homeposition of the z-axis? Needs to lower about 2.5mm

Please help! Thanks to all

[stevo1]

Do you have a macro program that does the tool change or is it done through the ladder? You will probably have to change your 1st reference position of the machine. If it is done via macro there is probably a position in the macro. It might use the 2nd,3rd, or 4th reference position if the tool change position is different from home position.

There is several different ways that this can be set up from the MTB. I believe in that control your first reference position parameters are #780-#783. These parameters are sometimes in metric or english. I believe it depends if you have metric ballscrews or not. These numbers are also entered with no decimal. And 4 places .0000 for english and three places .000 for metric. So if metric and you want to enter 3.1mm you have to type 3100 to get 3.1. If 31 is entered it will read as .031mm ect. You must also do a full power cycle the machine before the new value takes effect.

Stevo

[Al_The_Man]

If the Z axis motor was removed, which it probably was, your encoder home position has changed, this can usually be adjusted through the Z grid shift parameter, the adjustment in + or - is in encoder resolution counts.
I can look it up if you do not have the parameter manual.
Al.

[Stebedeff]

The servo motor was removed and so was the ballscrew. When tightening the ballscrewspindle the positioin is effected in hight as well. I have a KIWA EXCEL with same control and found the parameter for the hight positioning. As the bearing in the camshaft was broken when we bought it(2nd hand) the hight was set as 1800 in parameter(1.8mm). But now I fixed that too and put the posion back at zero. So now I can't find it anymore as I didn't wright it down. But that machine would go to z-axis homeposition. Then go up to Z 1.8 then change tool. This because it was set at 1800.
What I would really want (if possible) is to lower the zero position so that in this case the toolchange accurs at z-axis home position Like it used to. I 've tried to trick the machine but somehow the servo's are too smart for me. Unplugged the servo when at home position and turned the ballscrew till right position. Power back up by holding "P" and " CAN" and the home position did't change!
Guess I don't understand how the servo really works. And yes this machine uses macro for toolchange. But I don't know macro so it's all a big blurr to me.
And to Al The Man, I would love to have the parameter manual. All our machines (4) were bought second hand as we just started our shop 2 years ago. And that means we miss a lot of paper stuff. I have no fanuc manuals nor parameter manuals. So that would be a grate help.


Thanks to all!

[Al_The_Man]

I will send you a PM.
Al.

[Stebedeff]

Thanks Al. You The Man!