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Hello

Sorry if all of this has been covered else where as I am a bit brain dead after my attempts at torch height control using the external offsets branch. While testing I had the following "problems" that aren't necessarily problems with Gmoccapy.

1. I have a very standard xhb-04 pendant installed and working most of the time. From time to time I get the dreaded "lost connection" popup message and the pendant doesn't work (but appears to be alive). It always starts working again if I restart Gmoccapy. Is there a way to restart it without leaving Gmoccapy? I expect the problem is a temporary USB thing.

2. My old controller didn't require homing to work. I have installed homing switches and the table homes nicely with everything set to machine coordinates. My old work flow would have me placing a piece of material on the table and then using the laser dots move the sheet so it is square with the table and with the dots at the corner (origin) of the sheet set the part (material) X&Y origin. Is there an easy way to do this in Gmocappy or do I need a macro to set the part origin?

Thank You

John

First one is definetly not caused from gmoccapy. Imho the os change from ubuntu to debian caused that bad usb connection. If you look through the error output you posted in cnc ecke you see, that usb lost connection directly after being activatet.

Second one you have three options:
First
Add to your ini NOFORCEHOMING and you will not need to home, i definitly do not recommend this, as your machine will not react to the real soft limits and may crash.

Second
Home machine
Position your part
Push touch off button and zero x and y.

Third
Write a macro that zero x and y and use the macro function of gmoccapy to place a button in mdi bottom button, so you can home both axis with one click

You may even add a preample to all your code, to zero the axis before starting a program

Imho Second is the way to go

Norbert

Norbert

Thank you. I was sure the pendant USB problem was in the OS, just looking for a way to restart without exiting.

Yes, number two is the best for me. I don't know which button is the touch off button.

John

Tommy

Thank you, I am a bit red faced over this. I went out to the shop and found the button 10 minutes after I posted about it. Unfortunately I have had to disconnect the Linuxcnc control from my table and reinstall the old controller because I needed to get back into production. Maybe in a month or so I can have another run at it.

One thing I find nice about my present controller is while you are in auto mode running a file if you hit any key on your keyboard (I don't use a touch screen) it causes a "Feed Hold" to be asserted freezing X & Y axis movement and raising the torch while shutting it off. I can handle the torch control stuff but what about the hitting of any key causing a "Feed Hold"? Is this easy? Any examples?

I have been working on getting a Linuxcnc based controller for my table for the last couple of years. I finally got to the point of doing test cuts for THC tuning about two weeks ago. Alas things didn't go well with the THC tuning and I found a possible fatal flaw in the software that I don't know how to work around. I cut over 100 test lines but never could get the tuning down good enough for production work and then finally found the weak spot. Needless to say I am very disappointed to have to stop forward progress again because I need to be producing goods to sell.

John

John, I don't think the Gmocappy plasma screen has a touch off button. I've been using G92 to zero the X&Y by hand in the MDI window. One of the TODOs was to add a gmocappy macro to do this at the current position and maybe another macro button to touch off Z and zero the Z axis. I did play with this but must have had a bug in my code which then required a restart of linuxcnc to resolve. Another candidate for a macro button is to park the gantry right out of the way for loading.

Also, Linuxcnc has a gcode to rotate the axes around the origin. JohnT has a calibration routine that must use this to correct for a sheet that is skewed on the table. Might be worth checking it out as it might save some time. I've not looked at it.

Rod

I can't test if it works because I am not connected to real mechanics now but the button next to the homing button on the bottom of the screen is the one we are speaking about. My probing macro for finding the plate surface works well. I have a few improvements in mind to make it more reliable for production use. Most of these revolve around the conductive sensing of the plate so those that only use a float switch will not be interested. When you have 100s of pierces on a sheet this becomes critical.

JT's macro for positioning the work space to the sheet position sounds very handy for someone with an industrial sized machine or who uses thick plate. I do neither so I will just continue to push the sheet into position. I buy my steel directly from the slitter cut to a custom size that I can handle without machinery. The down side is that I have to buy 5,000lbs (160 sheets) at a time.

While licking my wounded pride yesterday I was reviewing my old notes on THC. I do see a way forward. While the approach we were pursuing is correct for a ridged machine with fast response we do know about the problems with plasma. I will actually use the eoffset_pid component as my starting point. I will need to add a few new pins and functions but other than that it is all there. I will not be using the add functions of the eoffsets branch in it's present form, back to 2.8 pre. I hope to test this in about a month. Good news is now I think I can change control systems in about 30min.

John