G91 G28 A0. at Force Tool Change

[motor-vater]

So I tried to hijack a different thread to get an answer but I think its not getting the attention I thought it would.. LOL I am trying to get my MP Master to output a G91 G28 A0. When I force a Tool Change and also when I do a tool change. The file I am working on seems through out a G91 G28 Z0 at all tool changes regardless of forced on actual tool changes. Seems like on a tool change it adds another line with G91 G28 Y0. A0.. But because of the nature of the Haas I am working on I am trying to insure that I keep it rotating in a CCW direction for repeatability. Some move will still go backwards. From A-270. to A-45. for example. For those situations I would love to force a tool change and get it to through out the trust G91 G28 A0. so it goes to zero and then to A-45 as to make sure it makes the correct rotation into position. Hopefully you follow me on this. Might be more a mater of the last operation generating the code as it would come before the operation that I would select the force tool change on but not sure.. Thanks for any takers...

[jlw™]

I'm not 100% sure I'm following you here but you should look in pretract for tool changes and pretract0 for null tool changes.  Unmolested MPMaster has logic in it to home rotary but you can # that out and just put in the code you want.  Look towards the end of pretract, you can probably find the *sm05 or the *sg28 "Z0." to get you to the area you want to work on.

[motor-vater]

Thats a great suggestion. I did play with the sg28 strings by adding "A0.", but did not see any change in my output which I found odd. Seemed like it would have been straight forward. I'll tinker some more tomorrow and see if I can nail it down.

 

What about rotational limits? I would like to let this thing wind up in order to keep it spinning in the same direction. Like go from A0. to A-45 to A-270 and then around to A-450 (currently instead of -450 it will go back to -90) . it seems like 360 is the max value the post will output is their a switch for that somewhere?

[Colin Gilchrist]

There are no rotational limits in any of the 4X Posts by default. 

[Leon82]

do you have a single direction positioning parameter on the machine? on fanuc it is g60

[Leon82]

I wonder if you use  a point path to navigate those areas you could get what you want

[Colin Gilchrist]

15 hours ago, Leon82 said:

I wonder if you use  a point path to navigate those areas you could get what you want

Or a Curve 5X path to reposition the tool above the part.