I'm new to this CNC routing and just got a 3018 to keep me busy in my retirement. However, I worked for the last 30 years on a Heidenhein machine... I have no mechanical limit switches fitted so rely on the $20 soft limit enable for safety. Setting this I was asked to switch homing enable on...which I did. I tested this out by pressing the Homing Cycle button but the first move of the Z axis crashed me into top of machine...went past zero machine readout. How is this possible if soft limits are set correctly.I tested them first by attempting to jog past them and it wouldn't let me.
Soft limits rely on having homing switches to determine one end of the travel. Soft limits take care of the other side. Avoiding the need for 6 switches, needing only 3. Without switches you cannot have Limits enabled. Homing with switches tells it where the tool is in relation to the machine, so from there it can calculate where it can and cannot move
So you are saying i cannot set soft limits if I don't have at least a mechanical set of 3 limit switches. But I did this and it stops me jogging too far. And, although I have not tried setting these yet, I think there is some length of table travel figures i can also enter at the bottom of the $ list. I would have thought the Homing Cycle would work on the Soft Limits if it insists both have to be enabled together.
Only somewhat true. Grbl “think” home is whereever you last reset or booted Grbl. From there it assumes soft limits to be relative to. If you always “fake home” sure. But switches is a couple dollars, avoids remembering to fake the home, is more reliable and more repeatable... so why not
Do read the Grbl wiki gnea/grbl It explains it all in great detail, no guesswork needed. Refer to all the $2x range and max travel parameters together (read each one to understand the interdependencies)
Thanks for your input ...well then i may order a set on Amazon or Ebay.. Its gonna add to the Spaghetti Junction of wires already behind my machine but...what the heck...lol
