Milling Issue

All things related to the Centroid Acorn CNC Controller

Moderator: cnckeith

wwolski
Posts: 34
Joined: Sat Feb 09, 2019 5:17 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
CNC Control System Serial Number: 78047383DD52-0131191593

Re: Milling Issue

Post by wwolski »

as I previously said,
ALL info will come at once
Thanks,
Wil
cnckeith
Posts: 3211
Joined: Wed Mar 03, 2010 4:23 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: Yes
MPU11 & GPIO4D -w/ 3rd Party Drives: Yes
DC3IOB: Yes
CNC11: Yes
CPU10 or CPU7: Yes
CNC Control System Serial Number: none
Contact:

Re: Milling Issue

Post by cnckeith »

nothing in cnc12 or computer this is going to cause this. this is a losing steps issue.

thanks for posting the report.zip, one big red flag is the values you have to overall turns ratio (motor revs per inch) which you have set to .2853 for X and Y
there is pretty much no way that is going to work, this is a total mechanical overdirve of the machine and the motor will not be operating in its happy zone. so either you have this number wrong or the machine is of not a good design. review / re measure .. when you turn the X and Y axis motor BY HAND one revolution how far does the machine move?

fyi typical router overall turns ratios are in the 2.5 to 1.5 range and milling machines are in the 5 to 10 range.
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
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
wwolski
Posts: 34
Joined: Sat Feb 09, 2019 5:17 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
CNC Control System Serial Number: 78047383DD52-0131191593

Re: Milling Issue

Post by wwolski »

Hi Marty,
Here's the missing info attached.

Homebuilt CNC from a Greenbull kit (buildyourcnc.com) https://buildyourcnc.com/Item/cnc-machi ... 4X-milling

The acorn, power supplies and stepper drivers are all housed in a steel server case with 6 fans for air flow.

The spindle is not controlled by the Acorn yet, but I will do that once this issue is resolved

Chain drives for x and y axes , and yes they are tensioned properly and not the cause of the issue.

Note: The schematic shows a separate power supply for each axis, at present ALL AXES share the AIKS 320 watt 36 volt power supply.
I will receive and wire in the other two supplies on Monday

Note 2: The Acorn is mounted on 1 inch standoffs

Note 3: I use a breakout board for the DB25 connections
Attachments
picture of control box
picture of control box
picture of the bad v carve
picture of the bad v carve
sausages2.cnc
cnc cut file
(31.6 KiB) Downloaded 3 times
Nema34stepper.pdf
Nema 34 steper (x, y and z)
(119.39 KiB) Downloaded 5 times
CW8060_driver.pdf
stepper driver(x,y and z)
(591.56 KiB) Downloaded 4 times
current wiring schematic
current wiring schematic
report_78047383DD52-0131191593_2021-03-28_15-25-33.zip
current report
(622.19 KiB) Downloaded 3 times
martyscncgarage
Posts: 7883
Joined: Tue Mar 28, 2017 12:01 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: Yes
CPU10 or CPU7: Yes
CNC Control System Serial Number: none
Location: Mesa, AZ

Re: Milling Issue

Post by martyscncgarage »

Based on your stepper motor information, the best operating voltage would be 64VDC
square root of 4mh x 32 = 64
I would be running a 48VDC power supply

From your drive manual, the MAX Pulse signal frequency is 75hz
SO you need to go into the Wizard, ADVANCED TAB and CHANGE it, currently you have it set to 100,000KHZ
The Wizard's minimum is 100,000hz so go into Parameters
F1 Setup
F3 Config
Password 137
Go to paramete 968 and change it to 30:
P968 = 12.00000 -
Acorn Step and Direction Frequency in (Hz) 0 = 200000 Hz

3 = 400000 Hz
6 = 200000 Hz
12 = 100000 Hz
30 = 40000 Hz
60 = 20000 Hz
100 = 12000 Hz


Change the frequency and retest.
Marty
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
wwolski
Posts: 34
Joined: Sat Feb 09, 2019 5:17 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
CNC Control System Serial Number: 78047383DD52-0131191593

Re: Milling Issue

Post by wwolski »

Hi Marty,

Could I run all 3 axes off of one 48v supply? ie 600W?
wwolski
Posts: 34
Joined: Sat Feb 09, 2019 5:17 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
CNC Control System Serial Number: 78047383DD52-0131191593

Re: Milling Issue

Post by wwolski »

Or a single 64volt supply since I have to buy a new supply anyway?
martyscncgarage
Posts: 7883
Joined: Tue Mar 28, 2017 12:01 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: Yes
CPU10 or CPU7: Yes
CNC Control System Serial Number: none
Location: Mesa, AZ

Re: Milling Issue

Post by martyscncgarage »

wwolski wrote: Thu Apr 01, 2021 12:01 pm Hi Marty,

Could I run all 3 axes off of one 48v supply? ie 600W?
Yes, that should be ok.
DO test with the lower frequency.....
If you make changes in the Wizard afterwards, the wizard will overwrite it and you'll have to change it manually again.

Marty
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
wwolski
Posts: 34
Joined: Sat Feb 09, 2019 5:17 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
CNC Control System Serial Number: 78047383DD52-0131191593

Re: Milling Issue

Post by wwolski »

Hi Keith,

The X and Y axes are controlled by a chain drive sprocket
pitch angle drive sprocket = 0.25
14 teeth on drive sprocket SO 0.25 x 14 = 3.5" travel per revolution, so 1/3.5 = 0.2857 revolutions per inch,

These values were tweaked during calibration and this machine has been cutting accurately for some time
on large and small work pieces
So you are you saying that the drive sprocket is too large(too many teeth) ?

Thanks,
Wil
wwolski
Posts: 34
Joined: Sat Feb 09, 2019 5:17 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
CNC Control System Serial Number: 78047383DD52-0131191593

Re: Milling Issue

Post by wwolski »

Hi Marty,
I don't understand this

You said that
From your drive manual, the MAX Pulse signal frequency is 75hz
so set Acorn Step and Direction Frequency P968 = 30 which means 40,000 Hz
I have no Idea how these 2 numbers are related

Thanks,
Wil

martyscncgarage wrote: Thu Apr 01, 2021 11:43 am Based on your stepper motor information, the best operating voltage would be 64VDC
square root of 4mh x 32 = 64
I would be running a 48VDC power supply

From your drive manual, the MAX Pulse signal frequency is 75hz
SO you need to go into the Wizard, ADVANCED TAB and CHANGE it, currently you have it set to 100,000KHZ
The Wizard's minimum is 100,000hz so go into Parameters
F1 Setup
F3 Config
Password 137
Go to paramete 968 and change it to 30:
P968 = 12.00000 -
Acorn Step and Direction Frequency in (Hz) 0 = 200000 Hz

3 = 400000 Hz
6 = 200000 Hz
12 = 100000 Hz
30 = 40000 Hz
60 = 20000 Hz
100 = 12000 Hz


Change the frequency and retest.
Marty
martyscncgarage
Posts: 7883
Joined: Tue Mar 28, 2017 12:01 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: No
MPU11 & GPIO4D -w/ 3rd Party Drives: No
DC3IOB: No
CNC12: Yes
CNC11: Yes
CPU10 or CPU7: Yes
CNC Control System Serial Number: none
Location: Mesa, AZ

Re: Milling Issue

Post by martyscncgarage »

Its the maximum speed the drive is capable of receiving the step signals from Acorn.
You have old drives. Mach systems worked on lower speeds.
It might be beneficial for you to consider upgrading to newer drives that can accept faster pulse train input.
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
Post Reply