Z axis crashing into the bed

[toyprints]

Hi everyone. New E3V2 owner. Im having an issue where the print head is crashing into the end stop and just tries to keep on going. i replaced the switch and checked the wiring. I have a 4.2.2 board and no BL Touch. I've flashed the firmware several times now trying to see if that is the problem. I've bounced back and forth between here and Crealitys official site for links. I don't know what i did but nothing is working. It's like the Z limit switch doesnt tell the machine to stop when its pressed. It doesn't trigger if i manually raise the Z axis (via the menu and motor controls, not by hand) either. Is my board funny or have i screwed things up? I've been searching for over a day now and find no answers yet. currently I have UBL - no probe - 5.5 4.2.2 installed. I have used the default 4.2.2 .bin too to no avail.
Does anyone have any pointers?

[K2Kevin]

Check the wiring, also... manually (disable steppers in menu), move the hotend (print head) to that far left side and lower the gantry until you hear a click on the switch. Is the HotEnd it touching your bed? If so, raise the switch and tighten it down. IMPORTANT... be sure that switch is aligned on the rail and not tilted.

Once the Z-limit switch height is set, time to re-level your bed.

[K2Kevin]

Then the only thing left is bad wire, wire not plugged into main board or in wrong position, or bad main board. right?

[toyprints]

Yeah I guess so. I was hoping there was a setting I hadn't found. Im really bummed, I got a couple nice prints right out of the box. I can probably find the wires at Micro Center or Amazon, right?
Thanks for your help!

[K2Kevin]

Yeah I guess so. I was hoping there was a setting I hadn't found. Im really bummed, I got a couple nice prints right out of the box. I can probably find the wires at Micro Center or Amazon, right?
Thanks for your help!

Im surprised you could ever get good prints without it being able to home properly. hmmmm WHAT ABOUT Z-Offset? What is yours set to? Have you ever changed it?

[toyprints]

it was homing just fine and then all of a sudden it wasn't. I've tried adjusting the Z offset aND THAT DOESNT SEEM TO MATTER, sorry caps laptop, either. It just keeps pushing down. I just tried pulling the wires and reseating them, no help. It's almopst like the printer doesnt do whats saved. I tried to change the home position, no help either. i guess Ill have to get a new board and see if that does the trick.

[K2Kevin]

What is the current Z-offset setting? Also, can you show a pic of the "Z-motor and rod" just behind the rail at the bottom.

[toyprints]

Offset is set at 0.0.
Pic attached.

[K2Kevin]

Well... I guess its time to install an ABL (CR-TOUCH) and ditch that Z-Stop switch altogether. You'll thank yourself anyway.

[toyprints]

You'd go that way over a new board?

[K2Kevin]

You'd go that way over a new board?

Well, I would contact Creality and explain so its covered under warranty, and STILL get a CR-TOUCH.

[toyprints]

Smooth. I shall do that.

[toyprints]

CR over BL?

[K2Kevin]

The Cura_JPEG_Preview.py that I had in scripts folder, assumed it was for this firmware.

Cura JPEG Thumbnail creator
Professional firmware for Ender3v2
Miguel A. Risco-Castillo
2021-07-01
Contains code from:
https://github.com/Ultimaker/Cura/blob/master/plugins/PostProcessingPlugin/scripts/CreateThumbnail.py

It did not work. The previous plugin options/view was also different (entries for size). Found the correct one.

[K2Kevin]

I see... Im not up on my Marlin drama, nor do I want to be. It's included you say? In the pre-compiled zip? Hmmm. I searched and didn't have it.

[K2Kevin]

OH, I should clarify. I did find it in the source. NOT in the pre-compiled versions (Which is what I use)

[K2Kevin]

NOT in the pre-compiled .zip version (Which is what I use)

[K2Kevin]

@K2Kevin
in this folder : Slicer post-processing scripts for Gcode Preview

Add that folder of files to the Pre-Compiled zip as well, and you're golden!

[K2Kevin]

Wait, did you try installing stock Creality firmware as well? And still had your Z-crash issue.

[K2Kevin]

How many months has this buggy software been downloaded and not resolved? How many printer affected? How embarrassing...

[BlueWings172]

@toyprints

See the photo below. Check the cable from the sensor side. I understand that you checked from motherboard side.

check if the wires are fully inserted in the white housing of the connector that goes inside the endstop. Try to pull gently on each of the wires and see if they come out of the housing.

I remember when I got my Ender 3 V2, I had issues with the Z endstop in the first weeks. I found out that it is a common issue with the Ender 3 V2 and that in my case one of the wires became loose and wasn't making contact.

Check the wire before investing in new board. You can use the X endstop wire or sensor to test. Buying a BL touch won't be a waste of money because it is an essential upgrade and will replace your z endstop.

Just out of curiosity, aren't the new Ender 3 V2's coming with 4.2.7 board now ?

Note: don't mind the markings of cable in the photo below, it is not the original and I don't use the sensor all together.

[K2Kevin]

I have used Pronterface (still have it on Mac). But I don't have the issues with this. Will try when this print finishes (few minutes)

[K2Kevin]

I know cura does have a field to run commands over USB when connected, don't know if it will display any response. Curious... Don't feel like looking that up, Ill just try it.

[K2Kevin]

Works perfectly. Great idea to check that switch. Not sure if OP is still watching.

Connecting...
Printer is now online.

M119
SENDING:M119
Reporting endstop status
x_min: open
y_min: open
z_min: TRIGGERED
z_probe: TRIGGERED
filament: TRIGGERED

Reporting endstop status
x_min: TRIGGERED
y_min: open
z_min: TRIGGERED
z_probe: TRIGGERED
filament: TRIGGERED

[toyprints]

I will take a better look at the connector. I did a once over when I built the printer. That wire is a bit short in my opinion. An extra half inch would be great.
I purchased a refurbished machine. Which, can be hit or miss I know. My first two prints after building the printer were great. Then I fiddled with stuff and here we are.
Thank you for your insight and the time you took to post a possible solution.

[K2Kevin]

Open the main board case and cut the zip tie holding that cable, you should be able to gain a little wiggle room. Sounds like its very possible that cable connection could be an issue, like we thought. I didn't realize this was used machine, you never know where its been.

[toyprints]

Lots to catch up on here. I'll be back in the morning.

[K2Kevin]

@toyprints

And note : Especially not a CRTouch, It poses a lot of other problems (does not work in HS mode, loss of precision beyond 16 points, etc... a lot of feedback in this direction in many forums)... rather a BLTouch!

I haven't had any of these issues, in fact the CRTouch has performed perfectly without all the "bugs" of the BLTouch. People have there preference, I don't feel one is any better then the other. Now if your talking about quality, fit and finish, CRTouch wins hands down, IMO.

[toyprints]

Ok. So I switched x and z. Both fail to home.

Installed compiled firmware and it still fails on Z.

Id like to get a touch sensor but I'm still not sure that will be the fix.

Contacted the dealer. They're most likely going to ship a new board.

Thanks for all the help.

[K2Kevin]

@tititopher68-dev Thanks for the info. With non HS firmware, is there still an issue to watch for?

[toyprints]

Quick update. Decided to gamble on the BL Touch.

A little hairspray and we're doing it. A little stringy. It's also cold in here.

Bed appears to be about as level as I can get.

On to learning Cura.
Thank you for all the help, again. Time to lay down some dungeon tiles!

[BlueWings172]

@toyprints

Looks good! Hope this ended your issues. You may wanna give UBL a try.

Curious was kind of filament you are printing at 210/85 C.

[toyprints]

I'm using grey inland tough pla. I turned the extruder up to 221 and the bed down to 75. After a soap and water cleaning of the bed, the 1st layer was near perfect on my first dungeon tile. No hairspray needed at all.
What is UBL?

[toyprints]

Oh wait, is that the mesh bed leveling in Marlin? I think I've got that down pat. I leveled the bed by eye while printing the stripes and then dialed in by stepping the z axis down/up. I e added the G29 command to my Cura start commands. It does appear to measure the bed before the prints, but I'm not positive it's working properly. It stops at 9 points and then begins printing. How do I know if it saved that mesh though?Still having some adhesion issues on the carborundum glass bed. However, I did not clean it between prints.
Does anyone use the silicone bed sleeves instead of the springs? I'm wondering if they'll help keep it in alignment.

[BlueWings172]

@toyprints

If the printer probes 9 points and stops, then you are using 3x3 mesh bed leveling. If you wanna be more accurate, you can use 5x5 which probes 25 points (you need to use the 5x5 points firmware for that). So more points, more accuracy. That said, it becomes time consuming if you are going to probe 25 points before every print, especially when you are doing calibration prints that take just 10 minutes.

So here comes UBL, which is the next level auto bed leveling solution. I use 15x15 UBL which probes around 155 points then saves it to the machine. You only have to do this once every week or month since the imperfections in your bed surface do not change.

Then before each print, only 3 points are probed and the machine start printing quickly. So with UBL you get more accuracy + much less probing time before each print.

To use UBL, you need to use necessary firmware, then add the below to your Cura starting code:

G29 L0 ; Load default mesh from EEPROM.
G29 A ; Activate UBL.
G29 J1 ; Get the bed tilt in 3-points.

don't forget, first time you have to go the Level Menu then Create New Mesh

Takes about 20 minutes then saves to memory.