UM3 Printhead lift switch problem

[geektech 0]

Hello UM community,

today we received our UM3. Sadly, our ride isn't as smooth as it was/still is with our UM2.

Apart from one axis not beeing assembled right (not clipped into the holders...no big thing, but QA should look out for that), we cannot use auto levelling or the second print core.

We setup the UM3 through the wizard, connected to our WiFi and updated firmware. Everything went perfect. Then we sent the first printjob, and the UM3 started auto levelling.

Failed => Same height detected for both print cores. Check levelling switch.

So we tried again, same. So we checked what was actually happening, and found out that the UM3 does not "hit" the thing that pulls/pushes the lever. It misses it by about 5mm every time, this the lever always stays in the same position.

We did a factory reset, to no avail. Same problem.

When we manually level the bed, manually raise the second printhead (since the printer can't lower it itself anyways), printing is fine, very fine actually.

When we manually switch the lever during auto levelling (manually raise the second print head after the first calibration round), printing also works like a charm (have to make sure the head is raised of course, so the printer wont ram it into the glass bed).

But no dice bringing the printer to correctly hit the lever-switch-thingy on the right axle.

What options do we have apart from sending it back (a shame)? Of course we could print our own lever-switch-thingy, but that of course would only be an option if we are out of warranty, which we are the exact opposite of.

Would XY recalibration help?

Any help is greatly appreciated.

best regards

Ulrik

[Krasnoyask 7]

Hi Ulrik,

There is a option in the calibration menu to reset the core switching position. It's easy to do and all the instructions are easy to follow in the menu.

I believe it's under system/maintenance/calibration/calibrate lift switch.

By the sounds of it this should have you sorted

[Krasnoyask 7]

On a second thought, it maybe worth checking your print head axis's are square and parallel to start with, as the switch would have worked before shipping. So perhaps shipping has also made it skip a tooth on the belt putting the switch position out just as you are experiencing.

Well worth checking.

[joeyv 0]

Hi,

I am having this same problem. My second print head is not able to be lowered or raised. Lift switch calibration does not do anything, no movement. Are there any other solutions for this? I've searched the forums/internet and have not found anything.

The only "solution" (more of a hack) I've found is this:

When we manually switch the lever during auto levelling (manually raise the second print head after the first calibration round), printing also works like a charm (have to make sure the head is raised of course, so the printer wont ram it into the glass bed)

The problem with this is that it must be done before every print. I'm also not sure if this will work if using the second print head for support, but am about to try. Thank you for any help.

Best,

Joey

[IRobertI 521]

Lift switch calibration does not do anything, no movement.

 

Could you describe exactly what happens? The first part of the calibration is all on you. You physically move the switch and then physically move the head into position. After that, the printer will home and test the switch on its own.

[fbrc8-erin 298]

Hi,

I am having this same problem. My second print head is not able to be lowered or raised. Lift switch calibration does not do anything, no movement. Are there any other solutions for this? I've searched the forums/internet and have not found anything.

The only "solution" (more of a hack) I've found is this:

When we manually switch the lever during auto levelling (manually raise the second print head after the first calibration round), printing also works like a charm (have to make sure the head is raised of course, so the printer wont ram it into the glass bed)

The problem with this is that it must be done before every print. I'm also not sure if this will work if using the second print head for support, but am about to try. Thank you for any help.

Best,

Joey

Hi, Joey,

I've got a video of the lifting switch calibration here:

Can you let us know at what part you're having problems? Are you pushing the printhead into the bay in the back right corner by hand when you run the calibration?

[kmanstudios 1,120]

I have been running into that lately and it is intermittent. Sometimes it says there is a difference in height. Sometimes says the lift switch thing.

I run a manual level and all is usually good. But will sometimes get those errors even after doing the manual leveling.

Sometimes the bed does not even go all the way up to the print heads. I have done z calibration, manual leveling, etc. But it is intermittent. Sometimes the plate just goes up and down and up and down. Sometimes I cycle off the power and all is good, sometimes not.

I am wondering if I have, somehow introduced or have, from another source introduced, some sort of electrical noise as I hear that can futz up the reading of the leveling sensors.

I have taken to just doing a manual level when it acts up and just print. Works fine, but something is interfering with the active leveling and I am not sure what it could be. And, it just started to happen within the last two weeks. I actually thought one of my plates warped funny, but nope, same plate will run fine many times.

Edited July 24, 2017 by Guest

[Marco_TvM 34]

@kmanstudios

It would help us to get the log files after it goes wrong with automatic bed leveling.

[kmanstudios 1,120]

@kmanstudios

It would help us to get the log files after it goes wrong with automatic bed leveling.

Cointainly, Nyuck, nyuck, nyuck......

You ahve to be a "Stooges Fan" to get that one, but it means, okee dokee.....

[kmanstudios 1,120]

@kmanstudios

It would help us to get the log files after it goes wrong with automatic bed leveling.

 

As per the usual, now that I mentioned it to someone, it is working. I cannot rule out change in electrical noise and such. But, I can do a log dump when this print finishes if that would give you any idea.

It went really wacky with the 0.8 core. But, it was being used in conjunction with the 0.4 BB core. I do not know if that is contributing to the issue or not. But as soon as I went to 0.4/0.4 nozzle combo, it is working.

Still want my logs?

[Marco_TvM 34]

Yes please.

If we can get information about this, it would help.

[kmanstudios 1,120]

Yes please.

If we can get information about this, it would help.

Otay...as soon as the current print finishes, I will try to remember to do a log dump. I have been printing up a storm and little to no downtime between prints so far. Just on a roll is all. I gotta get pics up too.....sigh........

I will post a link to the files as soon as I remember.

Now...LOOK! On the table top! It's a beep, a servo, NO! It's PRINTER THANG! Able to bend mighty filament with the heat of its nozzles, Faster than a speeding Prime Blob (ok...that ain't hard to do) Able to print tall things in ONE PART!!! It's PRINTER THANG!!

Edited July 27, 2017 by Guest

[kmanstudios 1,120]

And, here is where you can get the logs I just dumped.

Be aware that I had to cycle the machine off and on a few times while the buildplate went up and down consistently.

Other information:

Sometimes, when watching the process, it would not touch the nozzles.

Sometimes it would go up and down a few times, but would eventually settle down and either fail or not. Really no consistency.

Sometimes, it looked alright in action and would still fail.

Sometimes it would fail even after doing a manual.

Sometimes, I would just do a manual and it would print just fine, so, I do believe my manual leveling skills are ok.

All times the nozzles were cleaned (Char and excess material) and made sure that the material was not 'leaking' out. It would let a bit of filament out as it did the leveling sometimes during the process, but I am discounting those times as that can futz up the active leveling.

But, for some reason it seems to be working now that I tattled to the teacher about its misbehaviour.

I just am not sure if all the information is there in the logs. There are three logs (even though I rebooted more times than that).

Edited July 27, 2017 by Guest

[Marco_TvM 34]

Thank @kmanstudios.

Sorry for the late reaction, but had to do some other stuff first.

I will look into the logs asap and see if I can find anything.

[kmanstudios 1,120]

Thank @kmanstudios.

Sorry for the late reaction, but had to do some other stuff first.

I will look into the logs asap and see if I can find anything.

No worries... For what it is worth, things have been working ok since I made that post. 0.4 and 0.8 nozzles are both no issues this last week. This leads me to believe that some sort of electrical noise was introduced somehow into my environment. I understand that can play merry hob with the sensors.

[Kurt-Kirkeby 2]

Hi

 

I have struggled with this problem to day, and did the calibration serval times, and the manual procedure, suggested here, nothing helped, until i discovered the cured nylon droplet under core1, when I removed that the failure is gone