Me too
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ive also heard good things about linux cnc but iâm new to machining so baby steps i suppose.
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This seems to be an old thread but just in case someone else finds this usefull. Use g28.1 to store the toolchange position then g28 to go to that position for tool change. I usually make my g28.1 the same as my work zero but my Z 30mm higher.
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Can you please explain this better?
Well, you go to a position, somewhere where you can easily access the endmill and it clears the workpiece. You send the gcode G28.1 and that stores that position. Then when you want to do a tool change, just send G28, and it will go back to that spot. This way you dont need to rehome when you change tools. All you have to do is redo the Z axis home.
Not really, i dont have homing enabled.
g28 and g30 are just coordinate offsets. It really doesnât mater if you have homing or not. If you dont have homing, you move your spindle to a position you like and zero out your g30 and g28. The only difference with using homing is that those offsets will always be âconstantâ.
I think @PhilJohnsonâs description on this one is better, and Iâd add that you always have a kind of homing - it just might not be the homing you expect.
When grbl starts up, the current position of the spindle is special; itâs one of the corners of an virtual box thatâs called machine coordinates. Normally, grbl expects you to have homing switches and youâre supposed to run the $H macro after power-up. You can see in the code that $H is really special - take a look here.
Youâre right that you can just use G28 coordinates for a lot of things, but personally my life got a lot easier when I actually started using the homing switches. Especially when using Fusion 360, everything just assumes that you have machine coordinates set up correctly.
FYI, if you really are interested in how things work in grbl, I think the code is probably readable even if youâve never tried to read C before. Give it a shot!
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Iâm new to X-Carve, GRBL controller, and using UGS to send gcode.
I mainly do inlays and I use Carbide Create to create the designs & generate the g-code.
My machine is an X-Carve.
My typical process to carve a pocket for the inlay with a 1/8 or 1/16 bit. I then go around with an inside contour to create all the finest detail of the pocket.
When making a tool change, invariably I move the carriage. The carriage movement is not detected by UGS/GRBL controller. Thus any precision is lost and the next tool will be misaligned. Donât think a manual/visual reset of X & Y will provide enough precision.
What am I missing about using these systems?
How can the X & Y calibration/alignment be preserved across a tool change?
This discussion implies a manual/visual alignment & reset of the X & Y is the only option. Really?
Is there any way to upgrade the controller and/or steppers so that a manual movement of the carriages is read back?
Is this a situation where a lead-screw machine is better since you canât move the carriages manually/accidentally?
Thanks everyone.
It looks like the command $1=255 is the solution to this.