Hi,

that the only automated way to really return to a point is setting up limit switches.

Correct. However I would not call them Limit switches, these switches set the HOME position, they don't have to be at the limits. It is common to put them at the end or nearly the end of an axis but you don't have to.

For many years I ran my mini-mill without limit switches, but I did have Home switches, which were indeed a few mm from the ends of the axes. They were the best single addition I've ever made to my
machine. It meant that I could reliably start my machine and pick up from where I left off yesterday and also that Soft Limits worked properly. Given that I didn't have Limit switches having reliable
Soft Limits saved my bacon many many times.

My new build mill has six limit switches, one for each end of the three axes, and another three Home switches, close to the ends but not at the ends. They all have separate inputs, so if a switch activates
I know exactly which switch.

I can live without Limits but you really need Home switches.

Craig

Hi,

Quote

that the only automated way to really return to a point is setting up limit switches.

Correct. However I would not call them Limit switches, these switches set the HOME position, they don't have to be at the limits. It is common to put them at the end or nearly the end of an axis but you don't have to.

For many years I ran my mini-mill without limit switches, but I did have Home switches, which were indeed a few mm from the ends of the axes. They were the best single addition I've ever made to my
machine. It meant that I could reliably start my machine and pick up from where I left off yesterday and also that Soft Limits worked properly. Given that I didn't have Limit switches having reliable
Soft Limits saved my bacon many many times.

My new build mill has six limit switches, one for each end of the three axes, and another three Home switches, close to the ends but not at the ends. They all have separate inputs, so if a switch activates
I know exactly which switch.

I can live without Limits but you really need Home switches.

Craig

thanks again for the thoughtful reply.  I actually have switches setup at the ends of x and y and the top of z.  just haven't bothered to wire them up.  In the year I've been running cnc I had a lot of issues early on that caused a few months of downtime, so right now admittedly a bit gun shy of any changes near my controller!  I know I will eventually set them up... but not quite there yet.  again, very much appreciate you taking the time!

If you don't have homing switches or a unique and repeatable machine home position, it can indeed be challenging to ensure that the machine is always in the same starting position between sessions.
In such cases, one workaround is to use a fixture or a physical reference point on the machine table that you can reliably return to at the start of each session. This reference point can serve as a pseudo-machine zero, allowing you to maintain the relative position for your work zero coordinates.

wordle

thanks for the reply.  this was quite a while ago, but literally in the last week finally got my home switches setup... and setup G59 offset. 

Built many a guitar w/o using limit or home switches and the way I did it was not w a fixture (not at all a bad option or anything) but just mounting my work piece, moving to center, setting all axis to zero.  If I needed to shut down my machine I'd just return to zero and exit mach3 and save my xml file. 

Now that I've got homing setup... I do have some questions about that... I should probably open a new thread but on the off chance anyone who knows is listening:

I've setup g59 based on my home position at front/left/top of machine, but I want to work from center of my bed.  so if I manually move to center of my bed and save that as g60 offset... next week I go startup my machine again... what is the procedure for getting to that center?
If I understand, I have to go to offsets tab, select g59, hit ref all home to again find front/left/top of machine... then go to offsets tab and select g60 and it will reliably (assuming home switches are reliable) find the center position I saved?