Extrusion Upgrade Kit - Fan Shroud Hitting Side Wall!

[nighthowlers 2]

Hello Experts,

 

I just upgraded my UM2 to a UM2+ with the Extrusion Upgrade Kit. I followed all instructions, double checked, and completed it with uploading the UM2+ firmware from within Cura 4.5.

 

I notice that when the head homes or whatever process causes the head to go from front-left to home position the left shroud of the fan (the sheet metal) scratches against the plexiglass left wall. 

 

How do I fix this? I don;t understand why it would scratch against the wall because with printer off, when I slowly move the head left, as soon as the limit switch clicks, there is 2-3mm gap. So why is it scratching when in operation?

 

Any help is appreciated!

 

Sid

[gr5 2,267]

It shouldn't but I recommend you do a FACTORY RESET.  You upgraded the firmware, right?  Sometimes when you update firmware, some of the settings (e.g. nozzle purge location) get messed up.  Unfortunately you will have to relevel and it will try to get you to start a print (once it is warming up you can abort).  And you will lose any custom material settings you may have created (if you mess around with that kind of thing).

 

[nighthowlers 2]

Yeah I did update the firmware, verified that the correct firmware is on it. Even flashed it manually from hex file. I then also did a factory reset to clear up the EEPROM. It makes a screeching sound and I can see scratched up plexiglass of the left wall 😞

[nighthowlers 2]

Does someone mind actually sharing what the clearance between the left fan shroud and the left wall is on a UM2+?

[gr5 2,267]

I had the same issue and I just moved the limit switch a bit.  Maybe the switch isn't working at all?  You can home manually in the menu - make sure it's stoping at the limit switch and not going farther.  Also make sure that the rods going through the head are perpendicular - sometimes one of the 4 long belts slips s tooth.

 

[nighthowlers 2]

Thank you!

 

Closing this thread: I solved the issue by printing a small collar for the part that hits the limit switch 3mm early than what it used to. This creates enough clearance.

[tinkergnome 927]

Maybe the fan bracket of the new printhead is just bend outwards a little bit?

Can you show a picture?

 

It should look like this:

 

 

and not like this (yes - i know, that's the old fan bracket, but you get the idea...):

 

 

 

 

The overall width should add up to 98mm (approx.)

 

[nighthowlers 2]

Thank you @tinkergnome. I did try bending it a bit in, and even going ~1mm more than the spec you linked. It was still scratching and I suspect it is some manufacturing tolerance issue.

[tinkergnome 927]

10 hours ago, nighthowlers said:

It was still scratching and I suspect it is some manufacturing tolerance issue.

 

The lever of the end switch is also bendable (be gentle). There you have yet another possible manufacturing tolerance (if you want to call it so).

I have done it in the past to squeeze the maximum out of the build area (so more or less the opposite of your requirement 🙂).

But the spacer you made fulfills the same purpose of course.