Lowrider 2 perimeters(Concept)

Hey there everyone is there any way for me to set the parameters on thee lowrider 2. Examples Before making the belt reach the belt ends , is they’re a way to program my Marlin to already be set to avoid running into the wall!? Setting my dimension without end stop
perimeter_image8

You can set your bed size in configuration.h in this section:

// The size of the print bed
#define X_BED_SIZE 600
#define Y_BED_SIZE 600

And then you can enable software endstops in this section of configuration.h:

// Min software endstops constrain movement within minimum coordinate bounds
//#define MIN_SOFTWARE_ENDSTOPS
#if ENABLED(MIN_SOFTWARE_ENDSTOPS)
  #define MIN_SOFTWARE_ENDSTOP_X
  #define MIN_SOFTWARE_ENDSTOP_Y
  //#define MIN_SOFTWARE_ENDSTOP_Z
#endif

// Max software endstops constrain movement within maximum coordinate bounds
//#define MAX_SOFTWARE_ENDSTOPS
#if ENABLED(MAX_SOFTWARE_ENDSTOPS)
  #define MAX_SOFTWARE_ENDSTOP_X
  #define MAX_SOFTWARE_ENDSTOP_Y
  #define MAX_SOFTWARE_ENDSTOP_Z
#endif

This solution will only work if the machine is homed electronically first. If he machine is not homed, it does not know where it is on your table.

And there is a serious issue even if you home your machine. Most people who run these machines use coordinates relative to the workpiece for the actual cutting, so a G92 is executed in the physical/machine workspace to reset the origin. When this is done, Marlin realizes it is no longer homed, and the software endstops no longer will work.

There is a workaround using workspaces, where the machine is homed in the physical/world workspace, but the cutting is done in another workspace. I don’t know of anyone (including the active members on this forum) that is using workspaces.

Note that while having the steppers held up and losing steps is not destructive. It makes a nasty noise, but both the belts and the steppers are not harmed.

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20x25 meters? This is the new record!

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Sorry I have let you down but I have to let you know now it’s just a concept I was not trying to confuse anyone…Tried :disappointed:

Forgot to mention without endstops

On my Primo, I use workspaces, but I’m using RepRapFirmware on a Duet Wifi. As a result, once homed, it will not crash the trucks into the ends, and will not plunge more than 3mm into the spoilboard. Any code that attempts to move past those boundaries will cause the program to halt. It works no matter where I set the active workspace zero. It also requires that I home the machine before attempting to run any programs.

Cool what exactly does it require me to do to get over this hurdle

For any softstop mechanism to work, Marlin has to know where the router is in relation to the bed. You can do this manually and fool Marlin. That is, you would push the router against the origin and then run the homing sequence. Assuming Marlin is setup for normally closed endstops, when you home the machine, it will immediately think it is home because there is no endstops installed and therefore the endstop connection is open, it will back off, and retest, and still find the connection open, and then set that point as the origin. This will be a bit of distance away from the actual home position (5mm in the version of Marlin I’m looking at). You can reduce or perhaps even eliminate this distance by editing these lines in configuration_adv.h:

#define HOMING_BUMP_MM { 5, 5, 2 }
#define HOMING_BUMP_DIVISOR { 2, 2, 4 }

This section in configuration.h defines whether an endstop is expected to be normally open or closed:

// Mechanical endstop with COM to ground and NC to Signal uses "false" here (most common setup).
#define X_MIN_ENDSTOP_INVERTING false
#define Y_MIN_ENDSTOP_INVERTING false
#define Z_MIN_ENDSTOP_INVERTING true
#define X_MAX_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.
#define Y_MAX_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.
#define Z_MAX_ENDSTOP_INVERTING false
#define Z_MIN_PROBE_ENDSTOP_INVERTING true

Note if the reason you want to do this without endstops is because you are running a serial/series rig, you can hookup endstops on a serial/series rig (one per axis), and it will work.

I think it will actually report a homing failed and reset.

G92 might work. IDK.

I don’t have a solution for you. Other than setting soft stops, and always powering on in the lower corner. But I want to point out that it doesn’t hurt the machine to run into the boundary. The motors will skipp steps (which makes a crunching sound) but there aren’t any teeth gnashing or pieces breaking. I don’t know how many times you can hit the limits without breaking something. But I bet you will learn to avoid the edges before that happens.

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I know that G92 does not work. If you execute a G92, then the Marlin no longer considers itself homed.

always powering on in the lower corner.

This does not work either. Marlin does not consider itself homed when it is powered on.

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Okay I got you on that I feel like from how I’m reading your response is from 1 point to another point only mg horizontal. Is There still a little more that I can do to achieve more the end goal sir ? .

I hadn’t considered that Marlin might be that smart. I just tested it, and it is not. I disconnected one wire from each endstop switch and ran an XY homing sequence. Marlin considered itself homed, but there was a slight offset due to backing off for the retest.

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I’m sorry I don’t understand your question. In fact, I don’t really understand the problem you are trying to solve. As mentioned by both Jeff and me, hitting the end of your working area where the steppers will be held up and grind is a non-destructive operation. You do lose steps, so that cut is ruined, and it is remotely possible that softstops might save most of the cut. But beyond that, I don’t see any benefit.

For softstops to work (or any firmware solution), the firmware must know where the router is relative to the working space. Without endstops, you must set this point manually.

If you really wanted your solution without endstops and using Marlin and softstops, you would need to first do:

  • Set your bed size in configuration.h in Marlin
  • Enable min/max softstops
  • Verify that endstops are set for normally closed
  • Optionally edit HOMING_BUMP_MM to reduce/eliminate retest distance.

Then each time you want to use the machine:

  • Pull the router into the origin corner against some hard stops
  • Power up the system
  • Home XY
  • Navigate electronically to the origin position of the piece you are going to cut
  • Switch to a different workspace coordinate system ( G54-G59.3)
  • Execute a G92 to set the origin in this workspace
  • Run your job

Note that switching workspace coordinate systems and executing the G92 can automatically be added to your g-code file using most CAM solutions and some g-code sending solutions.

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The first four points must be done by modifying and reflashing Marlin. All are done by modifying lines in configuration.h and configuration_adv.h. If you need more explicit instructions for how to modify these lines, let me know.

Thank you sir