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Author Topic: G20/21 DRO displays  (Read 3206 times)

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G20/21 DRO displays
« on: March 03, 2011, 01:50:12 PM »
Native Units "Imperial".
DRO's Locked To Units.

Running a G21 file, the axis DRO's auto-convert as expected, no prob.
But shouldn't the Feedrate DRO also convert ? The G21 file shows 1000 for a feed rate and so does the DRO. Would this make the Imperial setup attempt to run at 1000 IPM ? I assumed this would change to 39.37 IPM (+/-)
Also, on the Toolpath screen, the Proghram Limits "Range" DRO's are all in metric. I would assume these should auto-convert as well .... but they do not.

Still struggling in the Stone Age,
Thanks
 :)

Offline Hood

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Re: G20/21 DRO displays
« Reply #1 on: March 03, 2011, 02:03:23 PM »
Think its just the axis DROs, cant be 100% sure as I dont think I have ever run old fashioned code ;)
 However I do know tool  offsets stay as native units so presume the other stuff does as well.
Should be easy to simulate, just run the code and time a move and see if its 1000mm/min or 1000IPM.
Hood
Re: G20/21 DRO displays
« Reply #2 on: March 03, 2011, 03:14:09 PM »
Feedrate is fine, just doesn't convert the DRO.
Machine Coords do not convert either, they seem to stay in G21.
I like to check the Program Limits just to be sure that I will be running where I planned to. A habit that I've gotten into that will probably go away if/when I get more comfortable with the machine.
I can live with it.
Thanks

Offline Hood

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Re: G20/21 DRO displays
« Reply #3 on: March 03, 2011, 04:01:22 PM »
Other thought would be to have a metric profile, that way everything would be metric and eventually you may start walking upright ;D

Hood
Re: G20/21 DRO displays
« Reply #4 on: March 04, 2011, 08:11:02 AM »
 ;D
Eventually ... maybe.

Seems like you say, only the Axis Part dro's lock.
A metric profile with a loaded G20 file does the same. All dro's change to the call in the code ... except the Axis Part dro's (if locked).
The large majority of what I get is G20, so as others go "upright", I will as well.
Till then, I'll have to keep the caluses intact on my knuckles.  :)
Thanks !

Offline Hood

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Re: G20/21 DRO displays
« Reply #5 on: March 04, 2011, 08:20:27 AM »
;D

Offline ger21

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Re: G20/21 DRO displays
« Reply #6 on: March 04, 2011, 11:46:51 AM »
Feedrate changes on mine. I wrote some sample code that did nothing but swap codes (G20/G21, G61/G64, G90/G91, G90.1/G91.1), to test my screen. I happened to run it yesterday and noticed the feedrate changing from 150ipm to 3810mm/min.
Gerry

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Re: G20/21 DRO displays
« Reply #7 on: March 04, 2011, 02:33:07 PM »
Hi Gerry, mine will do that also.
But, if I load some G21 code in a G20 set-up and let it run, the PART axis dro's are all that convert.
I also set up a METRIC profile, ran G20 code "locked dro's" and the FR and the Machine Coords stay in INCH.
Have you try yours with actual code ?
If not, please do.
Thanks Ger,
Russ

Offline ger21

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Re: G20/21 DRO displays
« Reply #8 on: March 04, 2011, 05:09:31 PM »
Your right.

But, I can kinda see why it doesn't.

Your g-code should have a feedrate in it (F word). If it does, then that should NOT be scaled, as it should be a metric feedrate, since it's metric code.
 If you're running code without a feedrate in it, then Mach3 assumes you're setting the feedrate correctly prior to running the code.

You can't scale the current feedrate, and not scale the feedrate in the code. So Mach is being consistent by not scaling the feedrate.

If your code changes (somewhere other than the start) from metric to Imperial, though, then the current feedrate will get scaled appropriately. So, if you're running in G21 and call an F1500, then call G20, then the feedrate will change to 59ipm.

Or, try this.

G90
G91.1
G20
F125
G0 X0 Y0
G1 X4 Y0
G21
M30
Gerry

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JointCAM Dovetail and Box Joint software
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