M91 in nakamura tw-10

[maximusek]

Hi!!

Maybe some smart head is able to help me - I work at nakamura tw-10 - first operation face off then I have to engage c-axis (left turret) so I use M91. Next operation milling c0, c90,c180, c270, part is quite simple.
the proplem is after turning chuck is in "nobody knows" position, I write M91 and g0 c0 to rehome chuck but it takes time, sometimes after turning I see c axis in 450deg. I cannot wait 3-4 sec. until chuck will be back in 0. Maybe someone knows how M91 works, I need details or some way to fix the problem and make it shorter.
Thank You Guys

[slavetothemetal]

Is there a setting in your control for the rewind of your C axis? What is the code to send your C axis to machine zero? G28 maybe?

[maximusek]

G28 allows me to rehome turret G28U0V0W0, I was using G0C0.0 to rehome c axis, maybe G28 that is the solution; first question - I have no idea whatsoever, I guess You are talking about parameters, but I'm not "so deep"; I think M91 - c-axis engage should rotate chuck to machine zero...anyway I'll try G28 maybe that is going to be faster, thanks Slavetothemetal...

[dcoupar]

Try this:

(engage c)
G0 G28 H0
G50 C0
(cut)
(cut)
(cut)

[g-codeguy]

Originally Posted by dcoupar Try this: (engage c) G0 G28 H0 G50 C0 (cut) (cut) (cut)

Didn't work for me. Main spindle turned instead of live tool.

I also would like to minimize the dwell time when the live tool is initiated. Best I could tell with a stop watch is the M91 is taking slightly less than 5 seconds. A 4 second cut in cycle time adds up when you have been running the same job for over 3 years.

[slavetothemetal]

Is there a setting for direction? On our Mori NL, I say M45(C axis engage) then G0G28H0. Is M91 your command for C axis engage?

[maximusek]

Originally Posted by g-codeguy Didn't work for me. Main spindle turned instead of live tool.I also would like to minimize the dwell time when the live tool is initiated. Best I could tell with a stop watch is the M91 is taking slightly less than 5 seconds. A 4 second cut in cycle time adds up when you have been running the same job for over 3 years.

- that is the idea to turn the main spindle to correct angle and do it in short period of time; live tool works when U use M89 - just want to remain I would like to talk about TW-10 Nakamura - that is the main subject

[maximusek]

Originally Posted by dcoupar Try this: (engage c) G0 G28 H0 G50 C0 (cut) (cut) (cut)

I saw G50 somewhere but I don't know much about that code, I was using G50 with G96 but I know G50 can be a big problem because of the offsets, if U know some good website with description written using language for normal people without PCHD, please send me a link, for this moment I don't want to use Gcode I'm not 100% sure how it works, thank You 4 your post dcoupar

[g-codeguy]

Originally Posted by maximusek - that is the idea to turn the main spindle to correct angle and do it in short period of time; live tool works when U use M89 - just want to remain I would like to talk about TW-10 Nakamura - that is the main subject

I am talking about the TW-10. Well, TW-20 in my case. You only want the spindle to turn enough to reach the programmed C-code. What happened for me was the main spindle ran at the RPM programmed for the live tool. And then the tool tried to move in the Z-minus direction into the part per the program. Not good for the tool, don't cha know.

My program is

M91
G50 C0

and runs fine, except for sitting there doing nothing for almost 5 seconds. This is the exact same thing as your original post.

I tried the solution 'dcoupar' offered. Maybe you didn't read my comments closely enough. I am not trying to change the question, but find the EXACT SAME SOLUTION AS YOUR ARE.

[dcoupar]

M91 is probably calling a macro or a sub-program. Check parameters 6071 through 6089 and see if there's a 91 in any of them. We might be able to adjust the macro to improve the performance.

[maximusek]

Originally Posted by g-codeguy I am talking about the TW-10. Well, TW-20 in my case. You only want the spindle to turn enough to reach the programmed C-code. What happened for me was the main spindle ran at the RPM programmed for the live tool. And then the tool tried to move in the Z-minus direction into the part per the program. Not good for the tool, don't cha know. My program is M91 G50 C0 and runs fine, except for sitting there doing nothing for almost 5 seconds. This is the exact same thing as your original post. I tried the solution 'dcoupar' offered. Maybe you didn't read my comments closely enough. I am not trying to change the question, but find the EXACT SAME SOLUTION AS YOUR ARE.

- I didn't want to be rude but that the problem is, tw-20 is a little bit different then tw-10, somebody else started talking about Mori NL, the point is I'm trying to get some answer and wait for details, I don't need to develop the subject from tw-10 to milling/turning centers If You know what I mean; I do know You cannot compare cnc's and use the same solutions for all of them, mine is quite old, I last much time to figure out connection between Y-axis knock, spindle break and c-axis, program was getting crazy so I wrote the post to get some info; dcoupar wrote M91 calls macro, I use this code for left and right turret and effect is the same in my machine nothing happens, maybe U can put hole block of the program, I belive not M91 is the problem but something before or after, use single block and try to find critical line. Sorry If I was being rude, but that problem absorbed me so much and really needs to know how to fix it... 4 Ya g-codeguy

[dcoupar]

Maxi,

Have you ever tried G28 H0 instead of G28 C0?