I had previously flashed the firmware on the SKR Pro 1.2 and the TFT 35 just fine, like I did the MPCNC boards last fall, for the Lowrider2 build. Steppers worked with no loading.
Now in the power up wired to the steppers, not in a case, the LCD starts in the touch mode then switches to the “Marlin” or “Touch mode” screen by itself after it connects to the SKR board, and won’t let me change it back, no case, no knob just bare. Pulled the LCD to do testing using CNCjs via USB. No obvious damage under the trusty old 15x linen tester magnifier on the traces of the LCD.
In the testing of the Lowrider2 today via USB with CNCjs, a Z stepper is growling like a chihuahua, no movement, when Z+ is used until it starts to bind, then I kill it, Z- works just fine . Z steppers going the right way +/- same way, just one growling.
Steppers/board/LCD bought from V1.
I usually answer questions here, and after several hours of forum searches, and research coming up with a goose egg:
Did total start over from 1. Gray flat wiring correct in orientation.
On the LCD, the black wiring from SKR Board to LCD very loose with the single wire not making good contact. Wrapped plugs with single layer of teflon tape to gain some friction. Series stepper wire also very loose, teflon tape again. Wondering if spec or quality control on the wiring slipping.
Tested Z, growling stepper replaced after LCD/Control fixes, still growled. Lead screw couplers reset. now smooth as silk. Growling stepper tested without fault. Still perplexed by that one. My speculation, unobserved as set screws tight, is that coupler on one side was slipping on lead screw.
Still working through this build. The start over from square 1 brought up a few more issues that I have resolved (more of as-built vs blueprint-build). Not ultimately the fault of the hardware/parts, though I still believe the wiring plugs are below spec. Got a Dupont connector crimp-on kit, those plugs are much tighter.
Doing a test today on wiring replacement, as the series wiring plugs are shaky. There was something that was in the back of my mind since I built my MPCNC. At a metro hardware store I found 6 conductor wire, 26AWG, in sheath. Same spec as the series wire kit. This was something that was in the back of my mind since I built my MPCNC. Standard telephone line gauge, on clearance for $9/100ft, 6 conductor. Worth a test, results to follow. Ohm resistance meets the test.
Are the conductors stranded or solid? I’ve seen both for phone wire. Solid is likely to fatigue and break over time if used where it has to move.
I picked up a roll of 4-conductor stranded wire for LEDs that has worked well for me for motor extensions, etc. I also had an old spool of Belden 6 conductor stranded shielded cable that I used for my Burly. Was excited to get a single run to each axis. Turns out running the end stops in the same shielded cable as the motor can lead to end stop noise. Solved by adding capacitors to the end stop connectors.