Displacement on the Y axis

[luisito 12]

Some months ago I upgraded my UM2 to UM2+ with the Upgrade Kit.

Lately I have found that some parts print with a full displacement on the Y axis direction.

Like in this picture:

http://support.zortrax.com/problems-with-incomplete-prints-m200/

Please look at the picture number 6. "Layers Displacement on the X or Y Axis"

The displacement is clean and across al the entire part, so I can figure out the problem is in the Y motor or the pulley/belt combination that attaches it to the upper Y axis.

I have tried to tight the pulleys, which were actually too tight already. Pulleys do no wooble and look clean (apparently).

I have noticed the Y motor was very hot while printing, at about 80C, while the X motor was about 65C.

Obviously this difference depends on the part being printed but I wonder whether 80C is normal.

The problem is random. I can print large parts without any problem and then print smaller parts that have the displacement. It happens more easily on parts that are wider than deeper.

Is there any recommended way to fix this problem? Perhaps replacing pulleys or belts or even the motor?

Any help is welcome.

Luis.

Edited October 21, 2016 by Guest

[neotko 1,417]

Did you also tighten the pulley on the motors?

Is hard to access. Also you could mark pulley/shaft so when it happens you can see the culprit.

[neotko 1,417]

Also motors can be that hot without problems. Is the stepper chips the ones that can't be too hot, but that need that you actually enclosed the whole printer.

How does the belt tension fells?

[luisito 12]

I have found that the guide bar where the Y axis pulleys are mounted (the horizontal bar located at UM bottom) is being displaced to the left each time the Y axis moves. If I leave it alone, it displaces to the left about 6 mm. I can see it protruding on the left side!.

Is there any way to stop this happening ?

[neotko 1,417]

Sorry I'm a bit lost. Can you make a fast video with the phone?

[IRobertI 521]

Is it this that you're seeing?

http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide#protrudingaxes

[luisito 12]

This is a picture of my printer:

https://www.dropbox.com/s/ib80exwiiub3akc/rod1.jpg

[IRobertI 521]

Yep, that looks like what I linked to. Follow those instructions and you should be good to go. What has happened is that the set screw on the pulley has come loose during shipping (probably) so that the pulley can move along the shaft. Since the pulley is what keeps the rod in place, the rod is free to move through the bearing.

[luisito 12]

In my printer there is no spacer between the pulley and the wall.

[neotko 1,417]

Photos please

[luisito 12]

:-)

I cannot take a picture of that place!

There is a spacer on the right side, but there is no spacer on the left side.

So I understand now why the rod is coming out through the left side.

[neotko 1,417]

I would contact the reseller...

[luisito 12]

The seller was Utimaker itself.

[luisito 12]

What size are the spacers on your UM2 printer ?

I can see the right side spacer is about 10mm, but, as there are two pulleys on the left side, which is the width of the spacer on the left side ?

[luisito 12]

I can see 10mm and 5mm spacers on the BOM list. So I will try with the 5mm spacer.

[luisito 12]

Well, I have printed a spacer.

I have disassembled the left side of the printer and have inserted the spacer succesfuly.

However, now I am unable to reasemble the panel on its place!

It was easy to disassemble but impossible to put it back on place. :-(

Is there any trick to reassemble the UM2 panels ?

[neotko 1,417]

Sorry I was away all day (ikea day yay..)

About the panels, no idea I never done that, maybe @IRobertI can share some of his knowhow

The spacers I think the basic step file is on the github, there's also a um2 full step file of the machine, that might help?

But why you took the panel to install a spacer? Unscrewing the pulleys the shaft should move freely to a side to have room to install the spacer.

Edited October 22, 2016 by Guest

[IRobertI 521]

Ouch, you didn't need to remove the panel for that job. The rods are always put in after the frame is built already.

I would probably slide the  two rods out of the way to make things easier to fit everything together. Unless you have someone who can help you out with aligning the rods into the bearings while you try to match up the tabs and slots of the side panel. Doing that on your own will be almost impossible I think. But if you slide the rods out it will be much easier. As mentioned, the rods are held in place with the pulleys so if you loosen the set screws on the pulleys on the opposite side the rods can slide out of the way.

After that it's just a matter of lining everything up and pushing it together. You might need to use some percussive persuasion (smack it! ) to get the tabs into their slots. If they still refuse to go in, check that the corners of the tabs have become bent slightly which can happen quite easily.

After that it's pretty easy to slide the rods back in place again. Place them in the middle so they don't protrude from either end. Slide the pulley and spacer (make sure you didn't drop one in the previous step) as far to the side of the printer as they will go, right up against the bearings, and tighten the set screws again. Tighten them hard.

If you need pictures and further explanation there's an assembly manual here:

https://github.com/Ultimaker/Ultimaker2/

edit: The direct link got mangled by the forum. Go to the link above and scroll to the bottom and you'll find the manual there.

Edited October 22, 2016 by Guest

[luisito 12]

Done!.

I had to use the rubber mallet.