BL-Touch on Ender 5 Plus

Hello,

I have the above. when Auto homing the BL deploys and works twice. The 3rd adjustment it doesn’t deploy and the hotend hits the bed.

Any suggestions? Is there some G-code I can put in the slicer or something like that?

Thanks in advance!

Hi Ron

I am assuming the BLtouch deploys and retracts 2X on startup?

by the 3rd time you are referring to when it starts to home, the probe moves to the middle.

Does the red light flash on the BLtouch Probe?
If the red is not flashing do you see the solid red light and the steady blue light on at the same time?
You may have to look carefully for the blue one, it’s pretty tiny.

Jason

The red light is solid, yes. I’ll test the blue light on Wednesday when I’m back at the printer. Thanks for the response

no Problem, we will get you straightened up not an issue.

If you want to create a video of exactly whats its doing that’s another option as well. Either way, we will work through it.

Jason

Thank you i posted a link to the video. The features of the forum wouldnt allow me to embed it.

This actually happened to me once before.

What ended being the solution was that I had the acceptable deviation amount set to be way too low in the firmware, for some reason as soon as this was flagged the printer would go crazy and continually ram itself into the bed.

Hopefully this helps you!
Matthew

How do i fix that?

Hey Ron,

I want to apologize, I don’t think the advice I gave you would help at all, so sorry about that. On further inspection of the video I am not 100% sure what the problem is, is this at the start of a print? Or is this just homing the printer, if it is at the start of the print something is definitely wrong.

In the case that it was only homing, what I could tell from the video was that it probed 2 times then the hotend pushed into the bed but the bed did stop right? From what I can tell you should just need to adjust your z-offset so that the nozzle does not hit the bed. Currently the printer thinks that the end of the nozzle is a little higher than it really is, so when it moves down it doesn’t know that the nozzle has already crashed into the bed. In order to help it to know the exact location of the nozzle you will need to tell it the offset between the end of the probe when the pin is down and the tip of the nozzle.

You can measure this with a ruler/ calipers and then adjust the offset, then start a print and change it slowly up or down until you have the perfect layer. I have included a guide below that goes into more detail, there are also many guides on YouTube that can help you out!

In the case that there is something that I missed in your video please feel free to get back to me and I can try and give you a hand with it!

Thanks,
Matthew

Thanks ill take a look. Thanks.

HI Ron

I had a look at the video, It may just be the Z offset is a little too tight. Check out Matthews suggestion if your still having issues let us know and we will work the problem

Thank you. The issue is the bltouch is not deploying properly. Is there g-code to fix this, or do I deed to replace it?

Hi Ron

there are a couple of things you can try first. The first thing I generally do with the BLtouch is to reseat all the cables, Both ends and retest.

Failing that I will remove and clean the BLtouch pin and verify at that time the pin is not bent. (bent pins cause most failures.) You can straighten it most of the time but it must move freely through the BLtouch body on deploy and retract.

While the pin is out, I generally shoot a little compressed air through the body to ensure there is no debris hiding.

Retest and see if the operation is better.

As a last test before replacement run this command it should run the Self-test on the BLtouch. If this fails replace the sensor or you are dealing with mainboard/wiring issues.
M280 P0 S120

You must input the above command through pronterface or other serial software when connected to your 3D printer via USB cable.

Let us know how you make out
Jason

Way above my skill level. I think after spending thousands on 3 different printers I’m just going to sell my Ender 5 Plus at a discount and pay someone else if i want anything printed.

Thanks for the comments.

Ron

All is good,

We can get you through the process, It’s really not as difficult as you may think. I have a couple of walk-through videos that will have you doing it in no time.

Jason

Hi there!

Don’t get discouraged, we are here to help! Another thing I would add on to Jason’s advice would be to connect your printer up to a monitoring service like pronterface and try it again! I have included a link below for how to properly set it up and connect it to the printer. Essentially what we are trying to accomplish with this step is to see if the printer throws any errors. When we connect the printer to pronterface it allows us to view everything that happens on the printer, including some error messages that may not be visible on the lcd screen.

What I would do is connect the printer up to pronterface and then do the normal homing procedure you were doing before using pronterface (just click the home all button). Next, watch the output terminal on the very right of the program, this should spit out any error messages that the printer encounters. If an error message is displayed just copy and paste it into here, and I can help you to find out what exactly it means. If no error message is displayed it is possible that there may be something else going on!

Thanks,
Matthew

Thank you. I’ve already got my Ender connected via usb so I’ll give your suggestion a shot tonight.

Perfect, let me know how it goes!

Matthew

Okay I’ve done some googling and I can’t find the ‘Save settings’ option on the printer. I make the z offset changes, Auto Home, then next time i turn on the machine my changes are gone!

Hmm that is strange for sure,

This might sound strange but you still have the card inserted into the printer right? Sometimes the settings won’t save unless the sd card is still inserted.

When you adjust your z-offset does everything work properly?

Finally, have you tried adjusting the z-offset using pronterface, this can be done by adjusting the values you would like to adjust (z offset in your case) in the terminal or on the printer, and then putting an M500 into the terminal, this saves everything to the eeprom.

Thanks,
Matthew