Developing Post Processors Mits 3015LVP & old Trumpf/Bosch
Posted: Thu Apr 25, 2024 4:40 pm
Hey all, had a customer turn us on to SheetCam recently, we're working through the trial version and getting post processors figured out now. I was going to start this thread to pick brains and document the process for others who might find it useful.
Background: We're a laser shop in central KY, USA. Primarily O2 cutting carbon steel, but growing demand for N2, air, stainless, aluminum, and galvanneal. Parts are a mix of job-shop-style unique runs and build to stock/order recurring runs. We're programming & running Mitsubishi 4kW 3015LPV/LC20 and Trumpf 1.5-2.5kW L2503/Bosch C220 machines, with an Acra/Mits CNC mill & a CNC press brake for support ops (tap, chamfer, bend, etc.). We're coming from BobCAD v27 with roots back in BobCAD v21 & AutoCAD 2000. I got frustrated with BobCAD back in the v27 switch and we did a lot of work on the post processors in-house to get them where we wanted. No previous experience with Lua, but I can get by with variations of Basic and G-Code.
Situation: If I can get these posts lined out, we'll probably pick up a couple seats and move to SheetCAM full-time for CAM (heck, we've already transitioned to QCad for CAD). Still working through tutorials and wrapping my head around SheetCam, but the documentation is already loads better than what i was fighting with BobCAD. I already have a tweak of the existing Mitsubishi LC10 post about 80-90% of where we need to be, and was planning to start from the "Trumpf L250" post to get the old girls going. Was able to roughly replicate a Mits cutfile for a part yesterday (the Trumpf still has a ways to go).
Questions:
1.) Trying to figure out cutter comp - with all the various machines, materials, and parameters in the shop, it works best for us to fight offset at the machine. Les got me started with OnOffsetRight(/Left/None). Just basically turning it on is already getting workable code for the Mits lasers - they just need G41/G42 kicked on for the lead in. They don't mind kicking it off/none while rapiding to the next contour. For the Trumpfs I need to figure out how to insert a G40 on the lead out move, otherwise they get emotional and error out.
2.) Line numbering - I'm trying to figure out how to "N###" lines of code. Every line or only appended to the start of each feature/contour is fine. Memory is so limited on the Trumpfs that we're already only numbering the start of features. This lets us readily pick back up a partially cut part that was interrupted, and has saved our bacon (or at least scrap) repeatedly.
3.) Automatic stock usage - I'm trying to figure out how to automate accounting for the size of the cutfile - the post was already doing material size X & Y when I started with it, but that's for the stock, not the part (unless you use part CAD to define stock). This is a nice-to-have that would partially automate something that is currently a manual process in our workflow.
Here's what I've got so far: I'm also welcoming to any hints, tips, or suggestions y'all might have for someone new to SheetCam - be they for tweaking/building post processors, plugin recommendations, best practices, or ???. Seems like it offers a lot of capability for the money, and I don't even pretend to have my head fully wrapped around it, haha.
Thanks!
Background: We're a laser shop in central KY, USA. Primarily O2 cutting carbon steel, but growing demand for N2, air, stainless, aluminum, and galvanneal. Parts are a mix of job-shop-style unique runs and build to stock/order recurring runs. We're programming & running Mitsubishi 4kW 3015LPV/LC20 and Trumpf 1.5-2.5kW L2503/Bosch C220 machines, with an Acra/Mits CNC mill & a CNC press brake for support ops (tap, chamfer, bend, etc.). We're coming from BobCAD v27 with roots back in BobCAD v21 & AutoCAD 2000. I got frustrated with BobCAD back in the v27 switch and we did a lot of work on the post processors in-house to get them where we wanted. No previous experience with Lua, but I can get by with variations of Basic and G-Code.
Situation: If I can get these posts lined out, we'll probably pick up a couple seats and move to SheetCAM full-time for CAM (heck, we've already transitioned to QCad for CAD). Still working through tutorials and wrapping my head around SheetCam, but the documentation is already loads better than what i was fighting with BobCAD. I already have a tweak of the existing Mitsubishi LC10 post about 80-90% of where we need to be, and was planning to start from the "Trumpf L250" post to get the old girls going. Was able to roughly replicate a Mits cutfile for a part yesterday (the Trumpf still has a ways to go).
Questions:
1.) Trying to figure out cutter comp - with all the various machines, materials, and parameters in the shop, it works best for us to fight offset at the machine. Les got me started with OnOffsetRight(/Left/None). Just basically turning it on is already getting workable code for the Mits lasers - they just need G41/G42 kicked on for the lead in. They don't mind kicking it off/none while rapiding to the next contour. For the Trumpfs I need to figure out how to insert a G40 on the lead out move, otherwise they get emotional and error out.
2.) Line numbering - I'm trying to figure out how to "N###" lines of code. Every line or only appended to the start of each feature/contour is fine. Memory is so limited on the Trumpfs that we're already only numbering the start of features. This lets us readily pick back up a partially cut part that was interrupted, and has saved our bacon (or at least scrap) repeatedly.
3.) Automatic stock usage - I'm trying to figure out how to automate accounting for the size of the cutfile - the post was already doing material size X & Y when I started with it, but that's for the stock, not the part (unless you use part CAD to define stock). This is a nice-to-have that would partially automate something that is currently a manual process in our workflow.
Here's what I've got so far: I'm also welcoming to any hints, tips, or suggestions y'all might have for someone new to SheetCam - be they for tweaking/building post processors, plugin recommendations, best practices, or ???. Seems like it offers a lot of capability for the money, and I don't even pretend to have my head fully wrapped around it, haha.
Thanks!