First start and platform don't stop until extruder nose - HELP PLS...

Support&troubleshooting
21
Dear Team support,
 
Since the repair on the last 23rd of july, the print worked well until today.
I paid attention to the start process because of the first experience at each print.
I am ready to switch off the print in case of problem when the platform kisses the extruder nozzle.
 
After one and half month of good usage of the print, this morning the platform still level up when it kissed the nozzle.
Happily, i i was able to switch off the print before any parts was broken.
 
Then the first issue occurred, i check all the step as the support asked to me in this topic (wires, connectors, …) and i restart the print to make an autocalibration process.
It was impossible to make it.
 
I know the same issue than on the last 8th of july.
 
On this picture, you can see the issue.
http://snag.gy/1eZiQ.jpg
 
 
My print worked well during 7 weeks after the first repair and replace the extruder cable.
 
Now, i don’t know if i have to change the hotend (i got one!) or if if the problem could come from another parts.
 
Since the first day, I doubt with this machine because i make the same experience than the first process of printing when it was unboxed. 
I wonder if this machine is part of a wrong series of machines from the factory? 
I wait after the support team to find the best way to fix it. 
 
Dalimai
22

Dalimali:

2wrkuud.jpg

23

Dalimali:

2wrkuud.jpg

I do both thanks .

24

well from the pic it clearly looks like your bed need to be properly leveled up,even at the naked eye there is quite a significant inclination...how do expect the printer to work?!

25

well from the pic it clearly looks like your bed need to be properly leveled up,even at the naked eye there is quite a significant inclination...how do expect the printer to work?!

The picture shows the nose embedded in the platform ......

26

Is your hot end getting hot? If there is solid un-melted plastic at the tip of the nozzle it can prevent the nozzle from making electrical contact with the PCB, in which case the printer doesn't know that the nozzle has touched the bed and so it keeps raising the Z axis waiting for contact. The basic height-finding feedback loop is very simple: it raises the bed until it senses electrical contact between the nozzle and the PCB. There are a number of things in this circuit: the nozzle itself (make sure it's clean), the PCB, the connector from the PCB to the motherboard (the small one) the wire from the hot end to the head PCB terminal block, and the big ribbon cable from the head PCB to the motherboard. If any one of these is open, the circuit will not close and the printer cannot detect the nozzle kiss.

Since your printer has been working and suddenly stopped, I would take a very close look at the small connector on the bed PCB, both male (PCB) and female (cable) sides, and especially the connections of the male header to the PCB. I damaged mine once accidentally while scraping parts off the bed.

julia

27

yes which is a consequence of how badly leveled your printing bed is

 

28

Looks to me like your adjusting screws may need to be tightened 3 to 5 revolutions until the socket head cap screw heads (SHCS) stick up a little more from the bed.  I had some problems leveling my bed when the top of the SHCS were almost flush with the bed because the holes in the bed were catching on the SHCS heads and preventing continuous height adjustment of the bed.  I'd adjust the screw several times with no change in bed level and then suddenly the bed would pop up a few tenths of a mm as one of the holes slipped off the screw head.

Mike

29

Is your hot end getting hot? If there is solid un-melted plastic at the tip of the nozzle it can prevent the nozzle from making electrical contact with the PCB, in which case the printer doesn't know that the nozzle has touched the bed and so it keeps raising the Z axis waiting for contact. The basic height-finding feedback loop is very simple: it raises the bed until it senses electrical contact between the nozzle and the PCB. There are a number of things in this circuit: the nozzle itself (make sure it's clean), the PCB, the connector from the PCB to the motherboard (the small one) the wire from the hot end to the head PCB terminal block, and the big ribbon cable from the head PCB to the motherboard. If any one of these is open, the circuit will not close and the printer cannot detect the nozzle kiss.

Since your printer has been working and suddenly stopped, I would take a very close look at the small connector on the bed PCB, both male (PCB) and female (cable) sides, and especially the connections of the male header to the PCB. I damaged mine once accidentally while scraping parts off the bed.

julia

the nozzle was warm and clean. 
I also check the small connection on the bed, the welds are good, I changed the bed to be sure 
The symptoms are similar to the first failure in July.
30

yes which is a consequence of how badly leveled your printing bed is

 

FORGET, you do not understand what happened.  :wacko:

31

Looks to me like your adjusting screws may need to be tightened 3 to 5 revolutions until the socket head cap screw heads (SHCS) stick up a little more from the bed.  I had some problems leveling my bed when the top of the SHCS were almost flush with the bed because the holes in the bed were catching on the SHCS heads and preventing continuous height adjustment of the bed.  I'd adjust the screw several times with no change in bed level and then suddenly the bed would pop up a few tenths of a mm as one of the holes slipped off the screw head.

Mike

 
This is a electrical problem when the nose comes into contact with the bed.
When I throw a print, I still have the finger on the switch to stop the process and avoid the damage.
32

The picture was taken after stopping the printer before major damage.

33

yes which is a consequence of how badly leveled your printing bed is

 

No. His bed is off-level in the photo because the printer failed to detect nozzle contact during auto-calibration, so the bed continued to rise beyond the point where it should have stopped automatically, pushing one corner of the bed down on its spring suspension.

34

.

35

No. His bed is off-level in the photo because the printer failed to detect nozzle contact during auto-calibration, so the bed continued to rise beyond the point where it should have stopped automatically, pushing one corner of the bed down on its spring suspension.

 
Thank you for your help Julia.
 
I also said that it was a second test after the failure of launching my impression.
I wanted to see if the issue occurred during an auto calibration.
 
I could only do an email to technical support but I think the issue is sufficiently serious because imagine the damage if I had not Turns off the printer ... So share my bad experience and especially to avoid prevent and remedy the problem before more is a bad surprise