Bearing question
I've only had my Mk3 for about 6 weeks, but have been noticing that it makes a strange clicking or grinding type of sound when it traverses from right to left along the X axis. It only seems to happen in the right-to-left direction of travel. I've also only really noticed the sound since putting the printer in an enclosure. Does this seem like it might be a bearing issue?
If so, can someone point me toward instructions on how to regrease the stock bearings or a good replacement option that does not require replacing any other parts? Thanks!
Re: Bearing question
Might be bearings. They ship with an oil that preserves, not lubricates. Did you clean and grease them when you built the printer? If not, it'd be worth the time to do so: Lithium or Superlube synthetic are common types used. It requires a full disassembly - but you might be able to do so by just removing the rods ... but be careful putting the rods back in - don't force them - risk of damaging the bearings is high.
Might also be something odd like extra drag on the filament causing the extruder to skip. More tension would help if that were happening.
Re: Bearing question
Can you superlube the rods while the bearings are attached and the printer is assembled in the hopes it will seep in there? Or is the seal on the bearings too good and will prevent the lube from properly entering the bearning itself?
Re: Bearing question
Can you superlube the rods while the bearings are attached and the printer is assembled in the hopes it will seep in there? Or is the seal on the bearings too good and will prevent the lube from properly entering the bearning itself?
Nope. The seal will do its job and keep it out. (and conversely, in if you disassemble it to do so)
Re: Bearing question
There is just enough sag in the rods the seals don't do a 100% effective job at keeping grease in. A drop or three of light machine oil can help. The rust prevention that ships on the bearings may prevent grease from working well, so a drop or two of machine oil will probably help the most. But you also could try a few drops of lithium grease. Anything is better than nothing.
But this is a bandaid - the right thing to do to protect the bearings is to pack them with grease: this requires disassembly.
Re: Bearing question
They ship with an oil that preserves, not lubricates.
Seems like that would have been helpful information to include in the manual. Can you point me toward a resource that would help me figure out how to apply the lube?
Re: Bearing question
If you plan on using the printer 24/7 - or have it printing a lot - you need to disassemble to where you can pull the rods from the bearings and clean out the oil and pack them with grease. I used a paper towel twisted and pushed through to remove the oil, I didn't bother with chemical degreasers, and then applied grease and packed it into the bearings using a small plastic rod until I felt I had filled the bearing. There is a Thingyverse part for SuperLube tubes that looks like it does a good job of packing.
I'd recommend removing the bearing to grease them. Trying to pack them when they are installed - only pulling the rods - would be messy.
If - on the other hand - your use won't be 24/7; my ungreased bearings lasted about 500 hours of print time before they began acting up. At 2000 hours they had to be replaced.
Grease tube cap / applicator
https://www.thingiverse.com/thing:2777079
Re: Bearing question
There are also models on thingiverse that screw onto the superlube tube and squeeze the grease right into the tracks.