I’ve been busy over the holidays. Here is a summary of the recent progress with the PrntrBoard V2 3D printer controller.
I decided to give the JLCPCB SMT Assembly service a try and ordered some TMC2209 driver boards as well as some semi-assembled PrntrBoard V2 controllers. Overall I was quite happy with the results.
Here is a picture of the driver boards. I tested all of them and they worked flawlessly out of the box.
These are the semi-assembled controllers. I use semi-assembled, because only the SMT components were populated and I have to spin my soldering robot to work on the thru hole connectors.
Next I tested the sensorless homing capability of the TMC2209 drivers. After some tuning of the sensitivity parameter is works very well. You can see one linear rail axis homing with no sensors in this video:
I also decided to work on improving the mounting of the drivers to the board. The driver boards were not very stable in the PCI Express slots and I designed these little plastic holders to fix them in place.
They are bolted to the bottom of the controller PCB. The drivers are very well affixed in place.
While I was trying to get my 2004 LCD panel to work with the controller, I found that not all “standard” EXP1 and EXP2 connectors have the same orientation. At first I though that the SKR 1.3 board, just has them backwards, but I then found this article on the RepRap discussion forum. It appears that the original schematics had an error and now some boards/displays are just backwards. I quickly flipped the connector on my 2004 display and with worked, but this can be quite frustrating.
I made a small PCB that one can use to flip the polarity of the connectors. “To flip or not to flip” seems to be ongoing question.