Help about to give up

Hey reprappers

I have been battling with this printer for a while now, revisiting it every couple months trying to get a bit further before getting wildly frustrated and moving on to another hobby for a while.

I have designed and built my own printer, its made from v-slot extrusion and all axis are TR8*8 lead screw. And z min is an IR probe.

I have had so many different problems from dealing with bad solder joints on chinese PCAs and trying to make a V6 clone work. (I have now bought a legit e3d V6 (worth every cent))

So I believe I have my hardware in a good position, I can auto home and auto bed level.

I can start a print and get good first layer adhesion, the problem i have now is i just cannot get past 0.4mm z height before it plunges the nozzle into the heat bed and looses position.
It doesn't make any sounds like the stepper motors are having trouble it just either drives the z axis down into the bed violently or it stays at the same height and starts drawing off somewhere else for a couple milliseconds before the printer resets.

below are some photos of my prints. they also seem to be larger than 10mm but i figure i need just dial that in when i actually print something,

things to note:
I get same issue at the same time if printing from SD or opening the g-code through proterface

(the first time i plugged in the IR probe it blew my arduino reg, so i have to run the arduino with usb power from laptop, (and have tried with laptop completly shut down just using usb power))

Im using Cura to slice

I have PID autotuned the bed and hot end.

the g-code is reporting 10days to complete the 10mm cube (must be wrong?)

thanks for your help.

So the 10mm cube I downloaded off the net was actually a 37mm cube..... lol

i found and attempted to print a 10mm cube.

the printer has the same fault at the same position of the 37mm cube.

to me this must rule out hardware as the fault? If it was a thermal shutdown situation it shouldn't have happened until later in the print of the 10mm cube.

im starting to think it might be slicer settings? Im using Cura, cannot really see anything appropriate to tweak.

When I use slicer I cannot get past an auto bed level with out the printer just resetting itself??

I have tried different SD cards now as well.

Is this right? It prints the 1st layer.
Prints the 2nd layer periphery OK.
Prints the 2nd layer infill from the long diagonal to the corner OK.
Then it either prints a circle or drops the hotend and does a move or a bit of both.
Just thinking:-
2nd layer has a different speed setting. The proper action would be a move to the long diagonal to complete the infill, possibly with a lift.

Check settings for the lift on move - is the direction correct. Check things like move speed, accel and jerk in case the move speed is to high/not compatible and causing motion issues.
Otherwise I guess we are looking at controller hardware issues.
In slicer, check what is being requested after the auto bed level. Its probably a move. Im no expert but I wouldn't be surprised if some of the software trips up if given stupid numbers by accident (put % in when you meant absolute, decimal in the wrong place, negative sign, etc)

the first time i plugged in the IR probe it blew my arduino reg, so i have to run the arduino with usb power from laptop, (and have tried with laptop completly shut down just using usb power


Go no further.... do yourself a favour and replace the arduino sounds like you have toasted some of the A-D converters