[adidoro]

Its a serious pain to try and use the limits of my bed because turning it on and off causes a little drift. changing tools also is easiest to touch off rather than figure out offset.
What I normally do is touch off the cnc tool to the zero position I create in solidworks/camworks.
so for example with 3-axis work, lets say I want to cut a 10" circle out of a 12" square piece of wood... I would set home to the center of the stock in solidcam, then touch off the CNC at the center of the 12" stock. so the dead center of the stock surface becomes X0/Y0/Z0. its always worked wonderfully before

For the 4th axis though, I have a steel shaft that I place in it which has a specific diameter... so I insert a tool, touch off the face of the steel shaft, then add the radius of it to the Z-axis and now Z0 becomes the dead center of the rotary axis.
Then touch off the side of the steel shaft and add radius, now I have X0 in the center of the rotary axis.
As for Y0, I always use stock longer than the designed part, so I generally add an inch or two from the very bottom edge and zero Yaxis

Yes but all of this can be made exactly the same with offset, when you touch off you can set zero position work offset, not zero absolute of your machine... I don't use Mach software, but in my controller software I can zero with a click any axis to whatever I want, to absolute, to work coordinate, to other coordinate system, to machine position, to user position and so on...

[viroy]

maybe I'm thinking about offsets wrong... this is not what Mach3 shows as the machine coordinate position, I never cared what the machine coordinate position is, I simply use the axis zero button with that turned off

[adidoro]

maybe I'm thinking about offsets wrong... this is not what Mach3 shows as the machine coordinate position, I never cared what the machine coordinate position is, I simply use the axis zero button with that turned off

I don't know this software but you have an offsets button on top, click that and see what shows and if you can zero only offset position (it should) and switch between offsets and machine coordinate to see the differences...
The machine zero should be on X and Y zero where can only move from in positive direction and for Z zero absolute should be up from where can move only in negative direction (or down).

Edit: X and Y zero absolute can be any corner of your machine at the end of travel in selected corner direction. (I did this edit to not receive other corrections). Anyway you need to define your machine in Mach software and CAD-CAM software the same with axis travel distances, to can manage the soft limits etc...

[viroy]

I have never used this feature and really dont know much about it.
I dont set any soft limits
Attachment 492454

See I normally just design a part to be cut with the home at either a corner or center of the stock.
I measure the thickness of the stock, facemill if necessary to match program design thickness, then cut.
simple as that, no machine coords or offsets.... just touch off the stock where the cam home position is, zero all axis and go

[adidoro]

I have never used this feature and really dont know much about it

Now there, move your machine to X and Y corner left in front off your machine, negative directions, and when it is at the end off travel zero the X and Y in machine coordinate in that window. Move Z up to end of travel and zero Z machine coordinate.
Then move to your part as you said before, or to rotary axis where your zero want to be, and there you zero work offset after touch off. And from now on use that work position to set offset, and leave the machine coordinate as was set.

Edit: You can also work with multiple work offsets as you can see in that window G54....G59, also from CamWorks you can post to any off them. For now stick with G54 the first one.
Also need to be a way that main window of Mach to show offset coordinate and to zero like before, but only the work coordinate, not machine coordinate.

[adidoro]

See I normally just design a part to be cut with the home at either a corner or center of the stock.
I measure the thickness of the stock, facemill if necessary to match program design thickness, then cut.
simple as that, no machine coords or offsets.... just touch off the stock where the cam home position is, zero all axis and go

Postprocessor is not working like that to permanently move machine coordinate system, that's why is called machine coordinate system, once is defined and input travel axis from that point, etc remain the same forever.
Work position offset or work coordinate system can be moved anywhere on the table anytime and is relative to machine coordinate system.
As I said before, you can do the same thing, like before, zero to work position and go...

Edit: Soft limits are in the main window, after you define your machine coordinate system and input your axis travel distances in mach software you can enable soft limits. Then when you load a g-code that is bigger then your machine can travel it will alert you. Also the machine will stop at the end off travel at soft limits without engaging the limit switch, if is done properly.

[viroy]

not sure I understand 100%

my motors are not indexing, so when i turn off the cnc, the motors de-energize and move a little, and when i turn it on, they again move a little and it has no idea... it drifts
So trying to define the working area I think would create nothing but problems... even a slight amount of pressure on the gantry moves it while turned off. I believe I set my machine limits way way outside its physical size so I dont have to deal with that... the limit switches will e-stop it if it attempts to go too far

obviously I dont run any programs that I know are outside my machine limits, and I always run the simulation in mach3 to see if there are any errors which would show that its going where it isnt supposed to be

ugh my brain is scrambled right now, I dont know gcode well enough and have never had to do anything but design the part, create toolpaths, match the cnc tool tip to the home position created in cam software, zero out all axis and start
I think to you it makes perfect sense, but Im not following whats going on here

Ive never used an H01 in my code

[adidoro]

not sure I understand 100%

my motors are not indexing, so when i turn off the cnc, the motors de-energize and move a little, and when i turn it on, they again move a little and it has no idea... it drifts
So trying to define the working area I think would create nothing but problems... even a slight amount of pressure on the gantry moves it while turned off.

obviously I dont run any programs that I know are outside my machine limits, and I always run the simulation in mach3 to see if there are any errors which would show that its going where it isnt supposed to be

That have nothing to do with work position as you set your work position after you start your CNC, so if your axis are 2mm off it will not transfer that to work position, as it will be set after. Anyway, do as you wish.

[viroy]

I'm just trying to understand what you are trying to teach me, I believe I'm just thinking in my own limited experience which is screwing me up in understanding.
from what I can gather, you want me to move my machine to the extreme bed limits and define that as the machine coords.
Then touch off to the stock home position to match the home position defined in cam, then set that as G54?

[viroy]

heres an example of a job Ive completed from start to finish, heres the process....
turn on machine, bolt down stock, load this Gcode, move tool tip to bottom left corner of stock, touch off, zero all axis, hit start, done
Attachment 492456

[viroy]

Is there a way to make the post processor output rotary movements as A instead of B?

[adidoro]

I'm just trying to understand what you are trying to teach me, I believe I'm just thinking in my own limited experience which is screwing me up in understanding.
from what I can gather, you want me to move my machine to the extreme bed limits and define that as the machine coords.
Then touch off to the stock home position to match the home position defined in cam, then set that as G54?

I'm trying to teach you minimum standard in CNC operations, first to be safe than sorry, second those all things like offsets and soft limits and many others was invented to be easy to work with the CNC machines.
Let say you have a part that need to be machined with 2 tools. You measure the first tool to material surface, right? Then you machine that surface and you need to change tool to continue machining but that surface has gone. Where you measure the second tool? That is why tool offsets exist. If you measure first tool offset, then measure the surface with that tool, when you change the tool need only to measure the second tool offset and go. Nice huh?
About work offset: Postprocessor have many variables to work with, like machine coordinate, example G53 that make that line of code to move in machine coordinate then next line in work coordinate. Those are standard. If you want to work with machine coordinate system is not like you do, to move machine coordinate to part, for that is work coordinate system invented for, so you can work in machine coordinate system from where it is, and your part and g-code will reference to that original position of the machine, witch is not very convenient.
But forget about 'Standards' and do what you want... There are many more things.
Standard: Machine Coordinate System is FIXED. not movable like work coordinate system.
All those 'standards' in CNC machining, CAD or CAM software, are correlated. If you disregard important one, like swapping axis name witch was demonstrated before, and you can't use others. Simple as that.

[adidoro]

Is there a way to make the post processor output rotary movements as A instead of B?

Only if that A is along X axis, otherwise will not work.

Edit: you can open g-code in notepad and do a search and replace B with A, job done if that's what you want.

[adidoro]

heres an example of a job Ive completed from start to finish, heres the process....
turn on machine, bolt down stock, load this Gcode, move tool tip to bottom left corner of stock, touch off, zero all axis, hit start, done

Same things to do with G54, "turn on machine, bolt down stock, load this Gcode, move tool tip to bottom left corner of stock, touch off, zero all axis, hit start, done"
What you don't understand?
In your code you already have G90 G00 G40 G54 - this is work offset.

Edit: Maybe you already use work offset but you don't know that.

[viroy]

here is how I deal with multi-tool operations...
If I need to use 2 different tools, I make a separate gcode file for each.

for the first tool, I touch off, set all axis to 0 and complete the first job.
When first job is completed, I place this (in the pic below) on the bed and move the Z-axis down until the tool pushes it to 0 and write down the current Z-axis position.
Now I can remove the first tool and insert the second one... then once again move Z-axis down until the tool pushes it to 0 and write down the current Z-axis position.

I then add or subtract the two z-axis positions to get the difference/offset... move the Z-axis to that position, re-zero the zaxis and now the second tool is the exact same height as the first.
Then load and run the second tool gcode


my machine doesnt have a collet for each tool, so every time I insert any tool, it can be at any height... unlike a tool changing cnc machine where each tool is in its own tool holder and the height is the same any time its inserted

[viroy]

"Maybe you already use work offset but you don't know that."
I think you hit the nail on the head lol
I really didnt realize that was happening.. im 100% self taught, this is a hobby for me, didnt take any classes, so im definitely missing some fundamentals

[adidoro]

here is how I deal with multi-tool operations...
If I need to use 2 different tools, I make a separate gcode file for each.

for the first tool, I touch off, set all axis to 0 and complete the first job.
When first job is completed, I place this (in the pic below) on the bed and move the Z-axis down until the tool pushes it to 0 and write down the current Z-axis position.
Now I can remove the first tool and insert the second one... then once again move Z-axis down until the tool pushes it to 0 and write down the current Z-axis position.

I then add or subtract the two z-axis positions to get the difference/offset... move the Z-axis to that position, re-zero the zaxis and now the second tool is the exact same height as the first.
Then load and run the second tool gcode

Now that is much more complicated and time consuming than tool offset.
By The Way, is almost 3 months from when you started this thread, go and make that cue. I expect pictures with the cue finished.

[viroy]

to create offsets for a specific tool, that tool would have to be the same height every time wouldnt it?

my spindle works like a drill press.... you loosen the collet by hand and insert the tool, then tighten with a wrench.
there are no tool holders for the cutting tool like on a cnc with an automatic tool changer.
so any time I insert a tool, it can be at any height... it will never be the same twice

[adidoro]

to create offsets for a specific tool, that tool would have to be the same height every time wouldnt it?

my spindle works like a drill press.... you loosen the collet by hand and insert the tool, then tighten with a wrench.
there are no tool holders for the cutting tool like on a cnc with an automatic tool changer.
so any time I insert a tool, it can be at any height... it will never be the same twice

Mine is the same, for tool offset you need to select the tool number, or can use the same tool number for each tool if you make separate toolpaths. You only need to have a tool measure fixed sensor, but i don't know how that will be set in mach software.
Tool offset can be measured every time you need for the same tool, the offsets will be updated with last measurement.

[viroy]

Is there a way to run the simulation from a fixed perspective rather than seeing the tool rotate around the part?
I would love to see the simulation from a stationary view as it would be in person while machining.