Ultimaker 2+ Print Head scraped the inner wall

[MGO 0]

Hi there

 

Happy user from France of a Ultimaker 2+ for years here.

 

That printer is used by several people at my work. Few weeks ago I used it again after a while, and I'm experiencing a very annoying issue. Everything's in the title.

 

The printer's head (more specifically its left side/the left fan) scrapes every single time the inner wall of the printer when moving along the left axis. Specifically at the beginning (the small movements at home head before going on the front left) or at the end of a print/after aborting a print (there, it scrapes all the wall when going to the home head, with a screeching and horrible sound). Or of course, when using home head function in maintenance.

 

See the picture attached. It is likely to be clearer. I played on brightness/contrast so you should notice the scrape done after few prints (not knowing what to do...)

 

 

What can I do? I browed the forum but I found no related topics...

 

Many thanks in advance !

 

MG

 

[gr5 2,271]

This is a common problem and easy to fix.  One thing you can often do is bend the fan back in by squeezing it but from the photo it looks like it's all the way in.

 

The other cause is the homing switch - it may have moved recently.  Push the head around by hand and when it is all the way to the left you will hear a click.  That's the homing switch.  Locate it - it's in the left top rear corner.  Just above it are 2 screws.  They may be loose.  Loosen the screws a bit and slide the switch to the right and re-tighten.  This homing switch sets how far to the left the head will go - the max position.

 

You can also bend the metal part of the homing switch.  But it can break so do it carefully.  You can also glue something on to that metal tab of the homing switch - like a few sheets of paper or a toothpick or something 1mm thick (you only need to move the head to the right by 1mm when homing to avoid scraping).

 

[MGO 0]

Hi !

 

Thanks for the quick reply !

 

For the fan, I confirm, it's in. That's more the metallic part below that is scaping.

 

A this exact moment, I'm doing a calibration/test print (we moved it, so I check it's still ok). So I can't check your suggestions on the homing switch. But i'll check later, straight when finished.

 

Although I'm a bit puzzled. The head doesn't need to be on the rear left corner/touch the homing switch to scrape the wall.

Typically, if I start a print, the head is in rear left. It makes some kind a of shake, and goes to front left, waiting to heat up and extrude a bit of material. Then if I abort, it goes back to the rear left, and scraping all the wall going there.

 

... And that's after spending minutes to write that, that I noticed the home switch I guess you were talking about. At first I was puzzled because I was checking the one on the left wall (so I guess for the max rear position). But I just noticed the one screwed technically on the "lid"/top and that is clearly for the max left position. I'll check when the print is done. Thanks !

[gr5 2,271]

Oh - it does the very noisy shaking?  That means it's not homing properly.  It doesn't detect the switch at all.

 

So either the switch fell off, or moved or the cable is broken somewhere.  First make sure you at least hear the click when the head is all the way to the left.  If you don't - that's good - it means you have a mechanical issue which is easy to understand.

 

If it *does* click then there is something wrong with the electrical wire that runs from the switch to the PCB underneath.  Maybe the cable isn't connected at all underneath (shook loose) or maybe one of the wires got cut by the corner cover - sometimes the cable runs under it and when installed it cuts the wire.  That corner cover that hides the steppers is held in by only 2 screws.

[MGO 0]

Oh, no, its not a noisy shaking.

I was just talking about the gentle wriggle it does a the beginning of the print. But it always did (the other Ulti2 we have as well)... yeah shaking was not a good choice of word !

[MGO 0]

Sounds like it's the home switch, thank you !

Clearly when moving the head to the left, I don't have the *click*, and I have to insist pushing it to the left to get it. That is clearly your call.

 

Unfortunately I can't find the proper screwdiver, and as everybody's on holyday, I guess I'll fix that later or find a way to attache something to have bettre "pressing" on the switch.

 

Anyhow, thank you for you prompt and superrelevant reply!

[Smithy 1,146]

You can also carefully bend the lever of the switch a little bit outwards.

[gr5 2,271]

If you bend it use 2 needle nose pliers.

 

The "screwdriver" is a 2mm allen wrench.