Very little progress was made over the weekend, we rather went geocaching on Saturday. Drove past House4Hack in Centurion - there is a geocache less than 100m away! There is currently not much work that can be completed on my Morgan, as much of the parts are still underway. This week I intend buying some endstops (Hall effect sensors), and a thermistor for the heated build plate. That will enable more testing of the firmware.
My heated build plate currently has a plate glass top. This might have to change, as I understand that the plastic (first layer) might not stick to glass as well as needed, and plate glass might have difficulty handling the temperature of the bed. I have read of borosilicate glass tops (probably expensive), and I have read of sticking Kapton tape on the bed to build on. If Kapton tape is needed, why not tape it directly to the heat bed (PCB)? A lighter bed must be a good thing.
I have polished the smooth rods (using the electric drill and Brasso polish), as well as the 22mm copper tube (for aesthetic reasons :-) ). I have also gone through the Marlin configuration code to see how the software distinguishes between 8825 (max 1/32 microstepping) and 4988 (max 1/16 microstepping) driver chips, as I have ordered Stepstick 1/16 (4988 based) drivers.
The microstepping is selected via two digital lines, and the (newer) 8825 stepper driver boards are configured to select 1/32 automatically when 1/16 (on the 4988) is selected in the software. So, it is not something I need to worry about - the resolution is lower than it could be but does not need manual intervention. Everything else is handled through the steps per degree constant. My Stepsticks are supplied with heat sinks and rated at 2A, so current handling should be good.
The power supply will be from my amateur radio - I have a 25A adjustable (switch mode) power supply that will be used for the moment.
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