Graphics showing mirror of machine movement

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cncsnw
Posts: 3763
Joined: Wed Mar 24, 2010 5:48 pm

Re: Graphics showing mirror of machine movement

Post by cncsnw »

For what it's worth, your "X AXIS BALLNUT..." program has the lead-in and lead-out in the back right quadrant (X+ and Y+), for the initial outside profile.

Where do the lead-in and lead-out appear when you use F8/Graph on that program?

Where do the lead in and lead out take place when you run it?

My guess is that, since your X axis movement is evidently correct, your Y axis is backwards.
cnc_smith
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Re: Graphics showing mirror of machine movement

Post by cnc_smith »

cad cam man,

In your first several post posts you said it is cutting correctly but it appears the graph is showing the X axis on the opposite side of where the tool is cutting on the machine. Just to make sure you are understanding the graph correctly. The gray lines are the edge of the cutter and the yellow lines are the center of the cutter.

Looking at your g-code for the circle at the end of the program MasterCam is not posting the g-code out correctly for the circle for the Centroid. It is turning cutter comp on with a G3 move and turning it off on the next move which is another arc then feeding Z down and repeating. Centroid will allow cutter comp to be on with a G1 Z move by it self. With any G0 move with cutter comp on the moves are moved to center of the cut not the comped moves. You will need to check the post in MasterCam to see what the setting that are wrong for circles with cutter comp on.
Dana

When requesting support, please ALWAYS post a current report.
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
cnc_smith
Posts: 237
Joined: Mon Nov 20, 2017 10:13 am
Acorn CNC Controller: Yes
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Location: Frenchville, PA

Re: Graphics showing mirror of machine movement

Post by cnc_smith »

cad cam man,

I hit submit too soon and had not mentioned about the approach at the beginning.

What is happening that there is not enough distance between the line turning the cutter comp on and the next line that is an arc. What needs to be done the line before cutter comp being turned on needs to be further away so the line turning cutter comp on has move clearance before the arc. Just for testing I took the cutter size down to .031 and the graph showed the approach correctly. So the G1 G41 move before the arc needs to be moved about .250 further away. Right now it is only .01 in X and Y
Dana

When requesting support, please ALWAYS post a current report.
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
cncsnw
Posts: 3763
Joined: Wed Mar 24, 2010 5:48 pm

Re: Graphics showing mirror of machine movement

Post by cncsnw »

I am fairly sure that his Mastercam-generated G code is precompensated for the 0.500" cutter, and that he is using G41 only for wear compensation. In his report, D2 = 0.0000.

The issues Dana points are will become important when the value of D2 is larger.
cnc_smith
Posts: 237
Joined: Mon Nov 20, 2017 10:13 am
Acorn CNC Controller: Yes
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Location: Frenchville, PA

Re: Graphics showing mirror of machine movement

Post by cnc_smith »

Sorry I missed about MasterCam being set up just for the G41 as tool wear comp.

For the circle MasterCam is not posting the circle out correctly even with the cutter diameter set to zero.

cad cam man,

After rethinking with the cutter diameter at 0.0 what happens the gray and the yellow are plotted on top of each other. When you put an offset in the gray will be the programmed dimensions and the yellow will be the cutter offset. If you put a negative value in for the cutter cutting oversize on an OD dimension(undersized on an ID dimension) the center line of the cutter moves off the gray making it look it is cutting on the wrong side of grey but it is not. It is moving the correct direction. The cutter is being moved 1/2 of the offset to correct for what the difference when it cuts and what was programmed as the actual size of cutter in MasterCam. The opposite is true when you put in a positive offset.

When you program the cutter comp for the cutter actual size to be comped at the machine you see the gray and the yellow is 1/2 the diameter away from the gray. If you put a negative value in you see the grey stays in the same place and the yellow line moves closer to the yellow by 1/2 of the offset. This move the cutting edge to cut the correct dimension. The same is true when the program is set up for the machine just to do wear comp.
Dana

When requesting support, please ALWAYS post a current report.
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
cad cam man
Posts: 44
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Location: south east texas

Re: Graphics showing mirror of machine movement

Post by cad cam man »

I have not had time to read over all the comments in detail but cncsnw is right the cutter comp is only for wear adjustments as mastercam deals with the tool diameter. After adjusting the travel limit and the reversal of the axis x is showing the exact same thing as the graphics as far as it being on the correct side . The y axis is fine there is no problem with it as it has done what the program and what the graphics have shown. As of right now the machine is working as it should the graphics window shows the same thing as the machines moves.
cad cam man
Posts: 44
Joined: Mon Mar 15, 2021 10:04 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: 4372
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: south east texas

Re: Graphics showing mirror of machine movement

Post by cad cam man »

I would like to add that when using mastercam it will show you and tell you that the cutter comp is either correct or it is not working and that was how I knew there was nothing wrong with that but I do appreciate the heads up
thanks
cad cam man
Posts: 44
Joined: Mon Mar 15, 2021 10:04 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: 4372
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: south east texas

Re: Graphics showing mirror of machine movement

Post by cad cam man »

cnc_smith wrote: Tue Nov 09, 2021 9:51 am cad cam man,

In your first several post posts you said it is cutting correctly but it appears the graph is showing the X axis on the opposite side of where the tool is cutting on the machine. Just to make sure you are understanding the graph correctly. The gray lines are the edge of the cutter and the yellow lines are the center of the cutter.

Looking at your g-code for the circle at the end of the program MasterCam is not posting the g-code out correctly for the circle for the Centroid. It is turning cutter comp on with a G3 move and turning it off on the next move which is another arc then feeding Z down and repeating. Centroid will allow cutter comp to be on with a G1 Z move by it self. With any G0 move with cutter comp on the moves are moved to center of the cut not the comped moves. You will need to check the post in MasterCam to see what the setting that are wrong for circles with cutter comp on.
This move is whats called a helical interpolation . Rather than plunging down in z causing the aluminum in this case to gall up and weld to the tool i used this method so it is cutting down in z and around in x and y . For this operation cutter comp is insignificant due to this being a rough out operation. The finish operation will be completed with a boring head. Since I can not use large drills ( large for this machine) I use this to get me close to size . Again thank you for the detailed observation I truly appreciate it as I use every bit of information to learn from
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