CNC 3020/3040 change board?

[john swift]

Not knowing what motors are used on the 3040 machines its hard to predict how well the grbr would drive them

with the stepper driver output limited to 2A
the torque will be limited and the low driver supply voltage will limit the speed you can step the motor

it may be worth looking at using linux instead of a windows PC running Mach 3
not sure of what the free ware is called

John

PS

http://linuxcnc.org/downloads/

this is where we need a linux user

[Lol999]

Hi John ironically I've just found several pages devoted to hacking the 3020.
https://www.instructables.com/id/302...CNC-Shield-V3/
https://hackaday.com/2015/09/08/how-...e-cnc-machine/

[john swift]

it looks like the A4899 Stepper Motor Drivers are better than I thought they would be

after looking at the two links

the TinyG motion controller shown on the hackaday page looks good
the only down side is the stepper driver IC's are soldered to the board
and not an easy DIY replacement

from that point of view the arduino grbl board on the instructables page
has an advantage with the plug in drivers

John

[Lol999]

Yeah part of me would go for the 8825 drivers as they are smoother yet with the smaller increments comes lower torque apparently.
we'll see what the birthday fairy brings and what extra I can add in the meantime.

[Lol999]

Interestingly this seems to fulfil the mod requirements for the 3020/3040 etc for virtually no money:
https://www.ebay.co.uk/itm/CNC-V3-Sh...53.m1438.l2649

[john swift]

yes
that will control the motors just like the tinyG for example
the only thing missing is the FET to switch the spindle motor on and off

with the arduino cnc sheild you have just linked to you can connect either a FET module or relay module to add the spindle on/off control



John

PS

check you don't need to add a 5V supply for the arduino
or 7 to 9V if you use the arduino's built in 5V regulator

the A4988 can use a 35V supply for the motors so if the 3040 cnc control has a 24V supply for the original stepper drivers that can be reused

the supply for the TI DRV8825 can be 8.2-V to 45-V

[john swift]

duplicate post