Cutter Compensation Question

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suntravel
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Re: Cutter Compensation Question

Post by suntravel »

If you set X and Y zero ist is always in the middle of the spindle not on the outside of he tool.

So without using cutter compensation a bigger cutter cuts the part at a different position than a smaller one .

Uwe
RJS100
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Re: Cutter Compensation Question

Post by RJS100 »

Uwe... Perhaps I did not explain the problem properly. I touched off the x and y properly. When I tested the location (G1 x0 y0), it was perfect. The tool was exactly where it should be.

I touched off to set the Z-height. I confirmed that the Z-height was correct.

After confirming the Z-height, I immediately tested the X and Y position (G1 x0 y0) again and this time the tool moved to a point about .8" to the right of the where it was when I previously issues G1 x0 y0.

What am I doing wrong?

Thanks... Richard
suntravel
Posts: 1967
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Re: Cutter Compensation Question

Post by suntravel »

There is nearly no way this can happen, if X0 and Y0 is set it will stay there.

Pls record the setting in G54 and compare them after setting Z0, may be you set not only Z0, but X and Y also.

Uwe
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Re: Cutter Compensation Question

Post by RJS100 »

Yes Uwe....Your comments are exactly what I would have expected... but now what I am finding. Very frustrating.

Image 1 shows the edge finder about .050 inbound in both the x and y directions from the rear corner of the part. Exactly where I wanted it.
Image 2 shows the x and y coordinates for G54

Then I touched the end mill off about 1 inch above the part just so I could run the tool path above the part for a sanity check.

Image 3 shows the edge finder moved over to the right (wrong position) after issuing G1 X0 Y0. The only change I made was to touch off above the part . The x and y coordinates are the same as indicated in image 2.

I am completely lost here. I uploaded my configuration file as well.

Thanks... Richard
Attachments
report_E415F6F649F8-0121214266_2022-11-18_16-34-34.zip
(882.52 KiB) Downloaded 5 times
20221118_163552.jpg
20221118_163633.jpg
20221118_163516.jpg
suntravel
Posts: 1967
Joined: Thu Sep 23, 2021 3:49 pm
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Re: Cutter Compensation Question

Post by suntravel »

You have lots of communication errors and E-stops.

Are you sure you homed after each e-stop?

With e-stop the drivers are disabled and an axis can move without updating position in Acorn.

Uwe
RJS100
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Re: Cutter Compensation Question

Post by RJS100 »

Thanks Uwe. Before working with the machine today, I worked on the communication errors. I disabled a setting in Windows that allowed the ethernet adapter to be turned off to save power. I also eliminated a RJ45 bulkhead connector. I did not see any communication errors today.

When I started the machine today, I pressed cycle start to allow CNC12 to home all axis upon start up. At this point I thought I had completed the homing sequence.

Is there something else I need to do? You mentioned "are you sure you are homed after each e-stop?" Is there something else I need to do?

Thanks... Richard
suntravel
Posts: 1967
Joined: Thu Sep 23, 2021 3:49 pm
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Re: Cutter Compensation Question

Post by suntravel »

Yes on open loop systems when hitting e-stop it is better to rehome because the drives are disabled in this case. Z axis can drop ect. and and the position is not what Acorn knows it is.

Uwe
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Re: Cutter Compensation Question

Post by tblough »

Next time you set your WCS, hit Alt-D and write down your machine coordinates. When it appears that your WCS position is wrong again, use your edge finder to re-locate the part corner and then check the machine coordinates again.

If both sets of machine coordinates are the same, then you are doing something to move your WCS. If the two sets pf machine coords are different, then you are loosing steps for some reason.
Cheers,

Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
RJS100
Posts: 380
Joined: Tue Oct 20, 2020 8:41 pm
Acorn CNC Controller: Yes
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CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
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CPU10 or CPU7: No
Location: Arizona

Re: Cutter Compensation Question

Post by RJS100 »

Thanks for your help!

I was questioning my height offsets and noticed that the numbers did not make any sense. I then looked at the proximity switches used during the homing sequence and realized that they actually MOVED.

For the x-axis, the round stop with the socket head screw actually moved over about .300 as it collided with the proximity sensor (see image).
Also, it appears that during the tool change request the z-axis collided with the proximity sensor at the top of the column (see image).

For starters, I am going to rework these brackets so the movement passes by the sensors so they cannot collide with them.

That said, I do not fully understand why during a tool change, the z-axis collided with the sensor. I would have expected it to decelerate before hitting the proximity sensor.

Thanks... Richard
Attachments
20221119_075809.jpg
20221119_075720.jpg
tblough
Posts: 3072
Joined: Tue Mar 22, 2016 10:03 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: Yes
CNC Control System Serial Number: 100505
100327
102696
103432
7804732B977B-0624192192
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Boston, MA
Contact:

Re: Cutter Compensation Question

Post by tblough »

The system will only decelerate approaching a switch if soft limits have been set in the control.
Cheers,

Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
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