Machsupport Forum

G-Code, CAD, and CAM => G-Code, CAD, and CAM discussions => Topic started by: greg2fs on March 20, 2014, 04:02:32 AM

Title: 4th axis turns for 359° instead of -1°
Post by: greg2fs on March 20, 2014, 04:02:32 AM
Hello, I am trying to use the 4th axis with solidcam, and in fact in works, but when it does movement outside the material a good thing would be that it wouldn't do a full rotation when it goes (for example) from 355 to 0.
Here is a gcode example:
Code: [Select]
S1000 M03
G00 G54 G90 X21.5875 Y0. A-88.588
G43 H1 Z30.
G01 G94 Z13. F300.
A270. F600.
G00 Z35.
X19.5875 A-88.588
Z33.284

Thanks in advance !
Title: Re: 4th axis turns for 359° instead of -1°
Post by: RICH on March 20, 2014, 07:08:14 AM
A few choices are allowed in configuration. See "Rotational" selections above Screen Control on the configuration page  and have a read of what they do in the manual .

RICH
Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 20, 2014, 07:12:47 AM
 This works with G0 rapids, but not with G1's.
(on the Gen Config page)

Russ
 :)
Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 20, 2014, 07:14:37 AM
ooops, that's one FAST bug you're riding there Rich.  :D

Russ
 :)
Title: Re: 4th axis turns for 359° instead of -1°
Post by: RICH on March 20, 2014, 07:22:03 AM
Hey Russ, no need for speed just better to enjoy the ride. >:D  :D

Have Cabin Fever yet?

RICH
Title: Re: 4th axis turns for 359° instead of -1°
Post by: RICH on March 20, 2014, 07:26:46 AM
Just somehing to consider on the rotation. If you have backlash it may be better to have it rotate in the same direction so  it is taken up.

RICH
Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 20, 2014, 07:29:07 AM
 no need for speed   >:D  :D

Have Cabin Fever yet?

RICH

Maybe that's not a bug ... .it's a TURTLE.

Heck yes, I'll be there !
You get us vendor passes yet ?

Oh yeah, good point on the backlash !  ;)

Russ
Title: Re: 4th axis turns for 359° instead of -1°
Post by: greg2fs on March 20, 2014, 09:48:39 AM
Sorry in advance for the following questions but maybe I'm too "newbie"...

Quote
A few choices are allowed in configuration. See "Rotational" selections above Screen Control on the configuration page  and have a read of what they do in the manual .
I don't find the setting nor "screen control" and what is the configuration page (settings or config menu) ?

Quote
This works with G0 rapids, but not with G1's.
(on the Gen Config page)
Same question for "Gen config page" do we speak about mach3 ?

EDIT: I seems that I have an old version of mach3, will try to update...


Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 20, 2014, 10:18:25 AM
(menu bar) Top left of the screen, click on Config.
Then in the drop down, click on General Config.
Then near the lower right you see the Rotational settings.
Russ
Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 20, 2014, 10:26:47 AM
 :)

If your version is VERY old, Mach2, it will be a bit different.
If this does not fix you, post your version .... or like you say, update to a newer one.
Russ
Title: Re: 4th axis turns for 359° instead of -1°
Post by: greg2fs on March 21, 2014, 03:58:27 AM
I updated from mach3 r1 to r3, now I have the options... I tested quickly the "Ang short rot on G0" and it does the trick but then say it should go from 359 to 0 with G0 now it goes to 360 but then it should from 0 to 361 in G1 but as it is already at 360 it go 361 but moving only for 1 degree, and it's not what I need as this turn have to be machined.
Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 21, 2014, 03:06:04 PM
I'm not exactly sure what you are meaning.
If you want to go G1 from 360 to 1 (361) by doing a full wrap, you can program G1 A-1 F# and it should go all the way around in the neg direction. (with Rollover checked)
Not certain as I don't use it. But it looks good here in simulation.

Russ
Title: Re: 4th axis turns for 359° instead of -1°
Post by: greg2fs on March 21, 2014, 05:36:37 PM
I'm not clear I know, sorry, but I'm not sure rollover works, last time I tried it did half turn, but I will retry...
I retry to explain with some code ("ang short rot on G0 checked"):
G0 Z10 A0          //will start at 0°
G0 A300             //goes to -60°
G1 Z5
G1 A0                //wanted to mill from 300 to 0 (-300° to mill) but just mill from -60° to 0° (+60°)

Is there a code to mill relatively, I mean instead of saying "go to 15°" or "go to 300°" , to say "go 50° more" or "go 10° less" ? THis way I should just modify the post processor to do what I want.
Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 21, 2014, 10:22:58 PM
G0 Z10 A0          //will start at 0°
G0 A300             //goes to -60°
G1 Z5
G1 A0  A-360              //wanted to mill from 300 to 0 (-300° to mill) but just mill from -60° to 0° (+60°)

Change the A0 to A-360 and it should do what you want.

You can also program it G91 Incrementally but any combined axis moves will be incremental also.
G91 is modal, so you will have to switch back to G90 Absolute as appropriate ... or program all Incrementally.

Russ
Title: Re: 4th axis turns for 359° instead of -1°
Post by: greg2fs on March 22, 2014, 02:17:34 AM
Quote
Change the A0 to A-360 and it should do what you want.
yes it's an idea, this way I still need to modify the postprocessor but it avoid using G91, thank you.
A question because I'm not an expert in gcode: will the same problem happen with curve ?
Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 22, 2014, 10:48:45 AM
......... because I'm not an expert in gcode: will the same problem happen with curve ?

I am far from expert ... quite far.  :)
If you mean G90.1 and G91.1 (Absolute/Inc. I J modes) and arcs, yes. The format is entirely different.
There are good explanations in the GCodes button on the Mach screen.

Cheers,
Russ
 :)
Title: Re: 4th axis turns for 359° instead of -1°
Post by: greg2fs on March 24, 2014, 10:02:58 AM
I finally modified the post processor, and don't have to use the two rotational options, thank you for your help.
Title: Re: 4th axis turns for 359° instead of -1°
Post by: Overloaded on March 24, 2014, 10:10:59 AM
I hope it works out well for you.  :)

Regards,
Russ

 :)
Title: Re: 4th axis turns for 359° instead of -1°
Post by: asitech on April 18, 2014, 06:34:31 AM
hi greg2fs
do u have post for solidcam that works?
cen u sher it ?
thenks
 asi
Title: Re: 4th axis turns for 359° instead of -1°
Post by: greg2fs on April 19, 2014, 05:14:06 AM
I'm not at home for two days but sure I'll share it if it can help...  I haven't tested it too much but the file opened in mach3 and the job seemed to do well.
Title: Re: 4th axis turns for 359° instead of -1°
Post by: greg2fs on April 21, 2014, 04:58:08 AM
I attached the post processor, hope it works...