Keeping zero position

Have you any intention of introducing into the controller program the facility of keeping the zero position on close down so that when you restart the machine it has the zeros you last used in place. I had a Shapeoko before buying the 1F and this has this facility, and boy does it save a lot of problems, especially if you have a power out or have to shut the machine down,

5 Likes

Hey Bill,

recategorizing to “Feature Requests”

Hey Bill,

An idea for a workaround that many people have and had in the past is to put the controller on an UPS. However there is still a problem with it, as described here: The UPS is able to signal to the controller that the power has gone but yet there is no solution how the nut daemon would trigger “pause”. At the moment it is easily possible to let the UPS trigger the “estop” mode on the controller, but that means loosing all positions so this does not help you. However it ensures stopping the milling motor and halting the machine’s stepper motors movement very quickly at power loss, which would prevent milling bit or workpiece damage.

I’ll definitely have a look at it one day, but I don’t run this controller (though I own one) and have no time at the moment!

Thanks for the idea, I just think it would be so easy for 1F to incorporate into their program, it would save a lot of head banging

I’m fairly new, but is homing the machine, and regaining the reference “zero”, by code, sufficient?

These seem like one-offs, or rare events, no?

While you’re at it, it would also be nice to preserve the “Park” and “Bump” (G28, G30) settings.

1 Like

Normally, but I am using the whole cut area and 1F says this can cause problems but so far have not given me a work a round why say it cuts 32 when it doesn’t do it all the time!

2 Likes

Park and bump? Out of my league,

Hey Bill,

Michael refers to stored numbered parameters, used in G28 and G30

Further Reading

Smid, Peter: CNC Programming Handbook, Industrial Press, South Norwalk, CT, USA, Third Edition 2008, ISBN 9780831133474

I will have a read. Thanks

If I understand your question correctly you are asking out to start your controller at the same home position it was in prior to shut down the way I do this is I return router to its home position before I shut it down when you shut down in the still be in the same spot but I always make sure to re zero the Z axis

I have zero expertise to even consider providing to this thread, but I won’t let that stop me :laughing:. Is there a way to capture the xy coordinates of your project’s origin position (like take a pic of it with phone), and then after powering back up, home the machine then go to those coordinates and reset the origin? I think we can manually send gcode commands to move the axis.

Yes I do this as well, it’s when you do not get a chance to do it like a power failure or you have to hit the stop.
I do take a note of my off sets everytime I start a new job as I know how to return to the presets. I just think it would be helpful if it would retain the settings on normal shutdown.

2 Likes

Amen I agree with you I love that onefinity get there are more than a few things that can be improved on that’s one of them.

2 Likes

Since Onefinity uses open loop stepper motors that can move while the machine is off, the big challenge after power off or power loss will be having a reliable zero point to start from that you can then apply your stored offset. This will be influenced by the required level of precision, stall homing in my testing was +/- 0.005" which may be good enough. I’ve moved to homing switches which are in the +/- 0.0002" realm (realistically there seems to be less error but my most accurate dial indicator is limited to 0.0002")

I also use fixtures for many operations where the corner of the fixture is my zero point, after power loss or when making another one of a part I use that as my work offset in CAM and on the Onefinity

4 Likes

I have a small white board stuck to the side of my touch screen the white board is permanently marked with X,Y,Z, Job thickness Z Datum & Cutter
At the start of a job or tool path I use a dry maker pen to fill in the blanks
X offset, Y offset, Z offset, Job Thickness in mm, Z Datum meaning is Z zero on the spoil board or the top of the material, Cutter diameter up or down or compression.
Its simple but it works, I was taught it in the 80’s during my engineering apprenticeship we used it on pretty much all manual machines and 100% on CNC’s which were a whole lot different back then

2 Likes

I have been asking for this since the onefinity came out.

2 Likes

What if the corner of the stock where its zeroed no longer exists because it had been cut away.
I would love to actually save the last gcode location so you could just pick up where you lost power.
Some jobs take a VERY long time and restarting them without being able to zero them is impossible.
I understand there may be work arounds but Im a programmer and these things are not all that hard to incorporate.

Yes it is easy, you must, once you have set your zeros, make a note or take a picture of your offsets. Then if you want to get back to the set position after you have shut down your machine follow these steps;
1 restart and home your machine.
2 open the MDI tab
3 type, g01x… y… The dots are your offsets that you made a note of.
4 press enter.
You should now be within 0.0002 of your last settings.
Hope this helps

3 Likes

I have a connected PC and use a web browser for controller screen. Hence, I have a text file where I store G code commands to enter as MDI code. Just copy and paste for start points. Example:
Lower Left Corner
G01 x7.014 y9.866
G02 X0 Y0
Copy G01 line and paste in the MDI window, click the run arrow.
Copy the G02 line and paste, click the run arrow. This sets the offsets. Alternate click the X set and Y set buttons (not the home buttons). Still have to set Z.
As far a I know you can only run one G code line at a time.
I have several “Starting Locations” for different setups stored in the text file.
Still have to home the machine once when the machine is first turned on.

4 Likes