You shouldn't need to take the head apart - it's unlikely it's the bearing in the head but it could be. Those are linear bearings - designed for a rod to slide through but not rotate. They contain ball bearings inside.
Instead, remove the head by the method mentioned above (just takes a few seconds) and then slide the rods back and forth through the head to feel the resistance.
Again - no need to take the head apart.
More likely the problem is one of the 4 X-axis bearings pressed into the wall or one of the two sliding block (x axis sliding blocks) bearings.
If you have the X stepper out then that makes it even easier to feel the friction issue. If there isn't more friction in X than Y with the X motor out then the problem is in the stepper which was your first guess.
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gr5 2,094
I watched (and more importantly listened) to the videos. The "bad" sounds are surprisingly mild. I was expecting nasty bearing grinding sounds (sometimes a ball bearing breaks and you get shrapnel in there and then the other bearings start to grind up). So that didn't seem like the issue but it's hard to say.
The stepper is almost certainly fine. It is supposed to have a lot of resistance to get over the first hurdle of magnetism and then it is relatively easy to turn. You can feel all the magenetic bumps when you turn them. These I think are 200 steps per rotation so you should feel 200 tiny magnetic bumps where it resists turning and then wants to turn 200 times per rotation. This is normal.
I would say it's the stepper driver except for your most important clue: "X axis its hard to push". If the X feels different from the Y then there is certainly a problem. So there are quite a few things to check:
1) The 4 axle bearings situated in the walls of the printer. One of those could be bad.
2) By the way did you try adding a drop of oil? Normally you add one drop to each of the 3 rods associated with X axis movement.
3) The sliding block bearings - I've had issues with these before when one of the rods that passes through the blocks had gunk on it. These are just simple brass tubes (no ball bearings - no needle bearings) as they have to slip rotationally and linearly both.
4) The rod through the head.
Trust the friction. You will know when it's fixed when the friction of the X axis is reduced.
First I'd check #4 that the two rods going through the head are perpendicular. Sometimes you lose a step and the setscrews for some of the long belts need to be loosened, the rods made perpendicular and then retightened.
Then I'd remove the print head. With zero tools you can snap the 2 rods out of the sliding blocks, then rotate the print head 45 degrees and it comes out and can be put aside. Test movement to see if there is still friction. If so then isolate - start loosening the set screws for the long belts to isolate each side and test #3.
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gr5 2,094
Also beware that some bearings seem fine once you remove the load. All those belts are applying a load because they are pulling pretty hard.
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K3Dds 0
Hi gr5,
Thanks for the reply and for the insight, you learn something new every day. I will take your advice and go through each of them to see if that alleviates the issue.
Just on a side note, I put the stepper motor back in and tried moving the head again along the x axis. It still has the same issue but listening more closely, it seems to be coming from the head- to your point #4. I will take the head apart and investigate, hopefully it will lie in there!
Again, appreciate the assistance
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