Hello. Could someone kindly explain what the cardinal direction Rapid Position buttons are expected to do? Are they immutable preprogrammed coordinates and if so what are they, or are they relative to user X0Y0 setting?
I have the 4 x 2 Shapeoko Pro 5 with running CM 651. I set all my projects to X0Y0 at the extreme SW corner polar opposite of machine home. The Rapids go generally but not precisely to the cardinal directionals. The machine’s total travel is 48.700" X and 24.528" Y. I would expect that the Rapids all go to either the extreme or midpoint of X and Y following basic 2D geometry, but they don’t. The edge rapids stop between about 7/16" and 1-3/4" from their travel limits. The center isn’t centered it’s X -24.37 and Y -9.528.
The reason I’m asking is I do a lot of moving material/parts on and off the table with locating pins, making parts in batches with many cuts which are similar but not identical. So I don’t have multi-hour multi-tool programs. Speed and ease of executing rapids and jogs to known points is important to be productive in this scenario. (I mentioned some of this in another topic where quick actions came up.)
I know my approach may differ from typical usage. I did find an older post that Rapids changed in the past year, but it wasn’t explained why. I would just like to know if what I’m seeing with Rapids is normal or I should contact support. Thank you.
The positions are hard-coded relative to the overall motion of the machine.
I wrote a bit about using them at:
Once the position of each rapid position is determined relative to the structure of the machine it should be accurate w/in the precision/accuracy of the homing switches and the steps of the machine movement.
Thanks…so looking at your older files, does it mean the rapids are purposely coded to stop some predetermined distance from the mechanical travel limit, perhaps to minimize risk of collisions with bitsetter or edge clamps?
Are the actual coordinates published so I can verify my machine rapids to where its meant to?
There doesn’t seem to be a pattern to it on my machine. Where they stop are a different gap from the limit in each direction and the center is almost 3 inches off the true Y center.
All distances on a Shapeoko are measured from the initialization right rear. When you set X Y and Z they are all relative to your homing position. The sensors used for homing have a +/- for repeatability. So if the homing position is slightly off from previous homing then so will your X and Y zero. So it is always a good idea to do a rapid position to your current X and Y before starting a job and specifically after a power on.
When you run the Setup function and define your machine type that will limit jogging to a predetermined point defined in shapeoko.json. C3D is on the cautious side when setting jogging limits. Some of that may be due to a legacy from the Suckit dust shoe. On the Suckit the wings of the shoe stuck out past the edges of the Z so C3D clipped the jogging to avoid hitting the rails on the X left side. If you edit your shapeoko.json file you can get a little bit more X travel. Just dont increase your X so much that you hit the physical stops.
During running gcode/.c2d files there is no limit on how far the machine will try to travel. If you tell your machine to travel a half mile in the X direction it will try. Obviously it will hit the limit. But jogging limit movement.
Thanks. It helps me to know the history of certain design or functional decisions. The homing and zeroing is working correctly. I have a fixture with index holes screwed to the table where I can verify there’s no offsets or change day to day.
I don’t see anything in the .JSON file to indicate a jogging limit. The Travel X and Travel Y settings are both the maximum machine range X: -1237mm (24.7") and Y -623 (24.5275"). I don’t see any other values that look like they’d affect jogging limits elsewhere in the file or the other .JSON files. Is there somewhere else to look?
These are the numbers for my machine and yours will be different. The numbers are negative and are the distance from the homing position. The only one you need to change is X and possible Y. You do not need to change Z because you can simply move your router/spindle up/down in the mount.
If you change the shapeoko.json file you must restart CM and I would power cycle the Shapeoko. Change a little at a time and jog to see if you are getting closer to the physical limit. Every change of shapeoko.json has to restart CM and power cycle Shapeoko. Do not increase so much you will hit the rails during jogging. Give yourself a little breathing room.