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Hi All

My Anet A8 is printing abnormally in the Y axis and the bed seems hard to move when I compare it to moving the extruder manually. It has been printing fine for a few months but recently it seems to be catching when the bed moves. For example, I can see the guide rods slide back and forth just before the bed actually moves. I think this is causing the printer to print too soon depending on which way the Y stepper motor is running. If you look at my attached image,

plussign
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it should be a plus sign, but the horizontal bar is lower than it is supposed to be on the right and higher on the left. I am thinking I should replace my Y axis bearings to repair this issue. Does anyone have a good reccommendation for bearings and or can you tell me If I am barking up the wrong tree?

Thanks

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I would look to your belt first. Disconnect and inspect it, look for cracks. Then with the belt disconnected try to move the bed. If the bed is still hard to move you will probably need to replace the bearings and maybe the rods if they have been damaged. I prefer IGUS bearings but which ones you need will vary depending on how your printer mounts the bearings.
If the bed is not hard to move, check your stepper cables and stepper motor. I have seen bearings in stepper motors go out, and I have seen intermittent connection issues, either in the connectors or breaks in the cable, lead to odd stepper behavior.

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I had a similar situation a while ago on my Prusa i3 Clone. I found the belt fastener on the bottom of the bed was loose causing some play when the y axis moves. So even though my belt was nicely tensioned, the bed was still loose and had play.

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Thanks for the replies guys. I solved this issue by replacing the bearings. When I disassembled the bed I found one of the tracks was very hard to move. The other items you mentioned all checked out ok. Also I took care to gradually tighten the screws holding the bearings to the stage and holding the cross bar to the 2 bearing sliders in a round about pattern which really helped a lot. I plan to print out an X axis cable chain and once it is ready I will be replacing the X axis bearings when i install it.