Solved X-axis not moving freely

Right in the middle of a test box print my x axis changed in it's sound. after the print i checked it and it has become stiff and difficult to move. I've lubed it with 3 in 1 oil *linear bearings stepper motor and belt bearings) It's a little better but not as free moving as it was before the print. Are there know culprits that go out this quickly on a new machine?

 

Is it difficult to move whether the printer is on or off?

 

Well I just took it apart. Seems one of the linear bearings is missing most of the balls on one segment. I guess I need to put in for a replacement part, since it is less than two weeks old.

 

Ouch, hope you get it in time

 

After seeing another thread with this same problem, I am beginning to wonder if Robo got a bad lot of bearings.

 

I was just looking at a deal 12 lm8uu and 6 608 bearings for $23. Seems like it might be a good idea to have spares on hand.

 

My first one, so I'm learnin' through thhe school of hard knocks which parts I need to have on hand, lol

 

There's some discrepancy on if the bearings are bad or if the smooth rods are too large.

I think their most recent order of bearings had some bad ones. Though we'd need some people with issues to measure the rods.

 

one rod (the one with the bad bearing) measures 7.89mm. The other one measures 7.93mm, according to my digital calipers.
(accurate to .0005 inch)

 

As long as it's under 8mm we're good. Just if it's over 8mm it could result in binding.

 

I think part of the problem is that if the x drive pulley is not aligned correctly it causes the belt to torque the X-carriage when traveling. This will be worse when moving in the positive direction since the belt length is shorter on that side. ( I noticed this while I had the cover off and checking the movement before I disassembled to inspect the bearings)

 

Got some new bearings in yesterday, so this morning I decided to put in a new set. While I have it apart I checked the diameter of the culprit rod. Seems the rod diameter varies up to .010 of an inch up and down the rod and over the diameter as you rotate it, so the rods are not round, nor are they consistent down the length.
Even the new bearings I got in, ( not from robo3d) at least one of them has missing balls in one of the tracks, so be sure to check your bearings before you install them.

 

how do you remove the linear X bearings?? I'm assuming you can't push them both out from the same side?

 

When I upgraded my X-Carriage with the chain I had to remove them, and I used this method from this video, helped a lot.

 

Do not pound the bearings out. Go to Thingiverse and print this:http://www.thingiverse.com/make:126859.
Basica;;y your using a 1/4-20 carriage head bolt to pull the bearings out. If your printer is down, then find an appropriate sized socket to use for a puller.

 

Oh, I agree, don't smash them out, but I used a bolt and my hand to add pressure, they popped right out.

 

as an FYI, per Robo3D support team, I used a #10 socket and a small hobby hammer and it worked perfectly.

 

If you're just replacing the bearing I push both through from the same side so the bad ones pop out the other end. I'd use a vise and a tube/pipe for receiving the bearings.