A rotation Question

[motor-vater]

I am a little stuck, not sure if its in the post or config. I have a part, engine block I need to machine at A45 and A-45. I set planes for each etc. but in the post it goes from A45, then to A315. Which is fine in theory except this block is to tall to rotate all the way around. I can manually edit the 315 to -45 but thats getting old. How do I fix this

[gcode]

You can edit the A axis properties in the machine definition

Try "Shortest Direction, absolute angle"

The other possibility is that the machine has an M-code for shortest direction

[motor-vater]

No go on that, any other thoughts? and Thank you

[nickbe10]

8 minutes ago, motor-vater said:

No go on that, any other thoughts?

There is also a switch at the top of the post (mpmaster  or posts derived from this, don't know about others) which also handles the post side of things.

[motor-vater]

Its a Milltronics post

[Aaron Eberhard]

Check your misc parameters for that the toolpath that you want to go to -45.  Look for the 3rd or 4th (I forget off hand) Misc Integer, it should be something like "Initial Primary."  This value tells the post where to start the rotary axis "from". 

For example, if you enter -40 in there the post logic previously would have been, "The first toolpath must be starting near 0°, so the shortest distance is +45°.  I've already moved 45° positive for the first toolpath, so I'm going to keep going that direction to cut down on backlash!" whereas now it will be "The first toolpath must be starting near 0, so I'll move +45°.  The second toolpath says it's already near -40°, so I'll just command it to go to -45° since that will be shorter." 

[motor-vater]

What should I throw in there

[gcode]

how old is this post

I'm thinking it's so old it doesn't support the machine def edits

SAVE A COPY OF YOUR POST !!!!!

then open it in a text editor and look for this

# 5 Axis Rotary Settings
# --------------------------------------------------------------------------
#Assign axis address
str_pri_axis : "C"
str_sec_axis : "B"
str_dum_axis : "A"

 

figure out which axis you're trying to change 

Secondary or Primary

 

then look for this

and make the appropriate edit

 

#Output formatting
top_map      : 0     #Output toolplane toolpaths mapped to top view
                     #The post must have code added for your machine control
spaces$      : 1     #No. of spaces to add between fields
pang_output  : 0     #Angle output options, primary
sang_output  : 0     #Angle output options, secondary
                     #0 = Normal angle output
                     #1 = Signed absolute output, 0 - 360
                     #2 = Implied shortest direction absolute output, 0 - 360

 

[motor-vater]

2002-2011 atleast according to the log at the top

[Colin Gilchrist]

Tom / Aaron,

"Unless I'm wrong (and I am never wrong), they are headed straight into the Fire Swamp." - Prince Humperdink

Sorry, had to get that quote out of the way first.

I spy "Misc Values" that are coming from MPMaster: Which is a 4 Axis Post.

There is no "Rotary Limit" logic available for 4X Posts, unless you make a Post Mod.

But, there is an option that might help you. In the "Rotary Axis Properties Page" (inside the MD), use the 2nd Option under continuous. (Signed Direction, Absolute Angle)

That should give you +45 for the 1st Rotation. Since the next position is only "-90 degrees", it should just output "-45", since that is the "shortest signed direction".

[motor-vater]

For sure, I've been mostly dead all day! lol Already tried it Colin, that turned the 315 into a -315... Yikes! LOL it is a MPMASTER post... says so.

 

[Aaron Eberhard]

9 minutes ago, Colin Gilchrist said:

"Unless I'm wrong (and I am never wrong), they are headed straight into the Fire Swamp." - Prince Humperdink

Always good to see a PB quote How have you been Colin?

Yeah, I was hoping that he had a more modern MP with the primary and secondary position controls..  I'm not sure how to do it on that post.

[motor-vater]

LOL I just change it to use the newest MPMASTER Post and that did it, Can it really be that ez? I have to still compair Gcode to make sure its good but hey I got A-45

[motor-vater]

A few subtle differences Ill have to mess with. The new Old Post includes  G49 in the first string, and the New MP Master throws a G28 Z0 in between ops and the I numbers are off by .0001

[Leon82]

The .0001 could just be rounding math

 

And there is probably a switch to output the g28 line . Or maybe there is a misc integer that is set 

[Colin Gilchrist]

5 hours ago, Aaron Eberhard - CNC Software said:

Always good to see a PB quote How have you been Colin?

Yeah, I was hoping that he had a more modern MP with the primary and secondary position controls..  I'm not sure how to do it on that post.

Hi Aaron,

I'm doing pretty well. My wife's health has been in decline, so I spend most of my time away from work being her caretaker. It's not the way I ever thought my life would turn out, but I just try to count the blessings I have, and take it one day at a time. She is starting a new medication soon for her M.S., and I'm hopeful that will help delay the progress of her disease.

The 4-Axis Posts don't have any logic to control the Rotary Axis Limits. It does look like it has been improved somewhat in MPMaster (at least according to the guy who started this thread), so I'll have to dig into that a little bit, to see what has changed.

[Aaron Eberhard]

11 hours ago, Colin Gilchrist said:

Hi Aaron,

I'm doing pretty well. My wife's health has been in decline, so I spend most of my time away from work being her caretaker. It's not the way I ever thought my life would turn out, but I just try to count the blessings I have, and take it one day at a time. She is starting a new medication soon for her M.S., and I'm hopeful that will help delay the progress of her disease.

Sorry to hear that, mate Hope the new medication works well for her and I wish all the best for you two crazy kids.

[?Mark]

Easy way to force the desired rotation is to add one or two simple drill toolpaths with the same tool at certain rotations to force it going that way.

[?Mark]

Sorry to hear about your wife Colin