Geeetech

Hi guys,

I've seen similar problems to this, but not a definitive solution, so here goes.

I've got an A10M and had the stock Marlin 1.1.8 in it, with Configuration.h modified to enable 3DTouch etc. It was all working fine, and bed levelling worked too (most of the time). Then it started crashing the nozzle into the bed sometimes, but not on the first probing (ie. right in the middle of the bed), where it worked fine, but always the second one at the front left of the bed. It goes down, the pin hits the bed and the light goes on (and the pin jumps up a bit), but the nozzle continues downwards and there is a nasty knocking noise as the motor can't go any further. Then the 3DTouch starts flashing, the nozzle goes up and I get a 'probing failed' on the LCD display.

I updated the firmware today to the very latest (9/1/19) because I saw a reference to 3DTouch issues, and now everything moves much slower, but still the first double probe in the centre of the bed is fine, but the second (front left) grinds into the bed.

What is going wrong ? It can't be the 3DTouch can it, since the first probing succeeds ?

Thought I'd update ready for the next person to experience this.

First I thought it must be a dodgy connection: it only happened when the nozzle was stretched away from the home position. Holding the wires as it moved to simulate the home position made no difference though, so I was stumped.

Then for some reason I decided to put the flat blade of a knife under the sensor, thus simulating the sensor being mounted down a bit - and bingo ! Probing succeeded for the first time in ages as I moved the knife to follow the sensor. Obviously I cancelled that print, lowered the sensor by 3mm or so and then went through the process of putting the measurements into configuration.h and uploading new firmware.

No idea why this works, but it does. Not had a problem since.