Connecting a CNC shield to Ramps 4.1 to run 4 extra steppers

I want to connect 4 extra stepper motors to my ramps 1.4 board using a CNC shield. I'll be running the extra motors using repetier host. However, i have no idea how to change the marlin software. The purpose of my project is to build a 3D bioprinter which would run 4 syringe drives which would be sliced along with the extruder to print filament and then tissue samples. I wonder if anyone can help with a wiring diagram from the ramps Aux 1 and 2 and the necessary code to change the marlin software.

Many thanks for your help

Jim Gillies

Why not choose electronics and firmware that already supports the required number of stepper drivers as standard?

You may find yourself short of RAM if you use 8-bit electronics, because the size of the movement queue increases with the number of stepper drivers .

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Many thanks for the reply. what sort of electronics and firmware could do this job?

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jimgillies
Many thanks for the reply. what sort of electronics and firmware could do this job?

The Duet series of control boards will support that configuration, without you even needing to rebuild the firmware (because all the configuration is done in a text file on the SD card). Duet WiFi and Duet Ethernet support up to 12 stepper drivers. Duet Maestro supports up to 7. See duet3d.com for more. The best place to ask for advice on using Duets in particular applications is [forum.duet3d.com].

See my signature for disclaimer.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

many thanks

jim