The MKS Base V1.5 is a great little board for a discount 3D print controller however I ran into one problem that had me stumped for a while so I’m passing on my solution for getting the second extruder functioning correctly.
Issue: When attempting to configure the MKS board to use a second extruder I found that it was extruding almost 8 times as much as the E0 extruder. I attempted to configure Marlin to us a smaller number of steps for the E1 extruder but that didn’t resolve the issue.
Problem: When flashing the firmware to the board I reviewed a bunch of posts that suggested that the MKS Base V1.5 was like the Ramps 1.3 or Ranps 1.4 board and to be fair when working with a single extruder it really seems to be. So when configuring Marlin I attempted to use the BOARD_RAMPS_13_EEB and BOARD_RAMPS_14_EEB but neither one would fix the issue.
Solution: Ok this gets a little weird because the fix seems unrelated to the problem but the solution is to change the pins config file for whichever ramps you are using. Just go to that file in Marlin and search for the pin names and change –
#define HEATER_1_PIN 7
#define FAN_PIN 9
I know that seems counter intuitive to fix the issue but I’m guessing the heater_1_Pin setting must somehow be used by the code to determine if the microsetps should be set to 16 on the E1 extruder.