My UP! has seen many prints since last maintenance and I noticed that it got a little noisier.
So it was time to grab the familiar hex wrenches and looking under the metal...
Once getting off the plates it´s a good idea too clean off the old grease from the rail, my old stuff was all brown and not looking that healthy. The Y axis was fine after cleaning and giving it some new high temp lithium rail grease.
While at it, check bearings too. A good idea is too remove the bearings and slide the rail by hand. Then you can easily feel if there are any obstacles or if it feels smooth. Do not slide it off the rail if you don't want to have a nice time putting in the balls again.
The Z axis doesn't really need that much attention, it doesnt get nearly that much stress as the Y and X axes.
My problem was in the X axis, the rail wasn't a smooth ride at all and the grease looked dirty. So after some cleaning the rail I gave it a new try but it still felt really bad, and the rail was shiny and free from dirt and particles.
I had no idea if I would survive taking off the sledge but I had to do something, so off it went and the balls poured out. It felt somewhat scary.
There was quite much brown/burned grease with small black particles in it. I took out the balls and cleaned them and the sledge itself in alcohol. After that I put in a thin layer of new high temp lithium grease.
The problem was putting the balls back and sliding it onto the rail again. Adding a little thicker layer of grease on the sides so the balls stuck there helped and only a few fell out in the end while putting it back on.
To get the last ones in just slide it on so there´s only room to push in one ball at the time until they are all in and then slide it on completely and make sure it feels smooth sliding it on the rail. If not, check if you got all balls in there.
Screw everything back on and make sure it´s square before tightening the screws. I also lowered the sound of the beeper before I put the bottom cover on because it´s really a bit too loud for me and wakes up half the house here when printing in the night. This was done with putting a piece of tape over the hole on the piezo beeper. Much better!
Put everything together and double check so you got all the cables in again.
Print the calibration and you´re back in business. My printer was so much more quiet, I haven't noticed it was getting that much more noisier but when printing again after this there is a major difference.