Using Nest tabs on a Laser

[MagnaFX]

Howdy, I had an inquiry on the tabs function within the nesting functionality paired with a laser cutter. Tabbing on a laser means you leave a little porition of uncut metal attached to the sheetmetal about .125 wide with 2 .1 or so legs. The tabbing function within nesting seems to be more geared towards milling, as it wants to use Zaxis vectors to leave a tab as you would with an endmill or sorts. My question is there any way to configure it to leave a horizontal tab?

[BurrMan]

I've seen a couple threads about this, looking to trigger an "on/off" for a tab. I dont rememeber if it was using dashed lines in a profile or setting up the post to output the on/off for a tab.

Maybe someone else can chime in on it. If not, I would need a sample file and your post processor so we can compare output with as-is and what you want.

[MagnaFX]

It seems that on/off is already on for us, however, the program does not have the right mcodes to close the shutter and reopen it, Our laser has pneumatic head that is just programmed to go down with an m code and go back up with another, i belive m24 is head drop and m 61 is laser cut off and m 26 is head up. When they created our post for me, all they took was a sample of the code as listed below and created a post off of it, as i needed it quickly. If theres any information on how to modify this post to get it to do what your saying, that would be awesome.


M24
G01 Y28.019 F50
G01 X8.748 Y28.019
G03 X8.843 Y28.114 I0. J0.095
G01 Y29.514
G03 X8.748 Y29.609 I-0.095 J0.
G01 X2.348
G03 X2.253 Y29.514 I0. J-0.095
G01 Y28.114
G03 X2.348 Y28.019 I0.095 J0.
G01 Y28.119
M61
M26

[SeanDa]

The software will allow for this with manual changes. Are you using the software strictly as a way to nest and then add the toolpath at the machine or are you also creating code from the program also. Below are the different options that you are able to have through the laser menu.

Manual - Since there is no automatic tool selection possible with this type of machine, only manual feeds are available.

Feed Rate - Sets the post processed feed to use while cutting.

Pierce Dwell - This items sets the time (usually in seconds, some machines may differ) that BobCAD-CAM will dwell to ensure a clean pierce at the beginning of a cut.

Pulse Frequency - This will set the pulse frequency to be passed to the machine.

Power Setting - This will permit the user to specify the power setting to be passed to the machine.

Torch Height Control - Some machines allow the torch height control to be set through the NC program. If it needs to be set for the user's machine, input the value here.

Arc Slowdown % - BobCAD-CAM permits the user to specify a feed rate slowdown for arcs. The percentage given is the percentage of the feed that the user wishes the machine to slow when cutting an arc.


Sean P Daugherty
BobCAD-CAM Technical Support

[MagnaFX]

Sean - Unfortunatly the only feature that i am able to program using this page is the feed speed and arc slowdown, Everything else is set at the panel of the laser itself. The problem i think i am having is needing the post edited to account for some of the other functions of the machine, as the only M-Codes that are functional in this post are M24 M61 and M26. I think i may have to resubmit a post request to your department and add functionality for the different M-Codes or find someone that knows how to edit these post processors. I am using bobcad to nest and post code that i then send through DNC to the NC. The code listed below is an example of what a nested part with a tab is coming out like

N0001G00X6.083Y46.623
N0002M24
N0003G01X6.183F50.
N0004G01Y46.994
N0005G02X6.438Y47.249I.255J0.
N0006G01X8.938
N0007G02X9.193Y46.994I0.J-.255
N0008G01Y44.494
N0009G02X8.938Y44.239I-.255J0.
N0010G01X7.44
N0011G01X6.183Y43.234
N0012G01Y44.239
N0013G01X5.162
N0014M24
N0015G01X4.652
N0016M24
N0017G01X3.438F50.
N0018G02X3.183Y44.494I0.J.255
N0019G01Y45.239
N0020G01X1.063
N0021G02X.808Y45.494I0.J.255
N0022G01Y45.994
N0023G02X1.063Y46.249I.255J0.
N0024G01X3.183
N0025G01Y47.251
N0026G01X6.183Y46.251
N0027G01Y46.623
N0028G01X6.083
M61
M26

This code demonstrates a simple exterior cut with a tab, the portion for the tab is between the two M24s written in the middle of the program. Now the problem with this code is that M24 is just an MCode for bringing the head down, and not for turning the laser off. What I would like is to have this use the M-Code to turn the shutter off or the laser cut off for a quick second, or even put a manual tab with legs in that leave room to re-pierce the metal.