Y Axis Bearing Alternative

I may have one part that didnt fall apart..lol

 

One of them was broken in half when I took my first robo out of the box. I printed new ones in ABS and PLA on my replicator 2 ( that I now sold )

So yes they are tight and they are upside down as per waldos instructions.

 

If a is interested in this mod, ultibots.com has everything 10% off the whole forth of July weekend with coupon code SAVE10%

 

Some are interested in the 10mm alternative to this modification. I've designed alternates for the pillow blocks and the end caps of the Y axis to accommodate that and made them available on Thingiverse as a remix. Cheers.

http://www.thingiverse.com/thing:1735555

 

Did you ever find a solution to this? I just got mine installed and I'm having similar issues at each end of the Y axis. It also seems that the printer is missing steps at the end of the axis. Any ideas?

 

No I never did, its something to do with the pulleys on mine the problem comes and goes. If I take the belt off its super smooth, belt on it binds. I tried all sorts of washers and spacers..etc. the belt rides up and down no matter how I adjust it. Havn't figured it out.

 

I may have figured out the vibration, or made it slightly better. I ended up having the wrong size washer on one bolt so it was higher than the other.

I also am running the belt a lot looser now.

It seems like the main cause of the vibration is the belt doesn't go down the middle its offset and causes a sideways pull on the rods which makes it vibrate like crazy as it goes through the bearings. I was able to reproduce it with the belt off by pushing on one side of the carriage instead of the center.

Right image had 2 fat washers on accident.

 

Nope that didn't fix it, it still vibrates like crazy at the extremes of Y. its because of the belt, its butter smooth when i take the belt off. I don't really know how to fix it at this point. Other than go back to stock bearings.

 

I think i'm going to switch back to stock bearings I have monkey'd around with this enough trying to get it perfect and just can't seem to.



This is what the vibrations cause..wiggly lines, makes for really bad walls on prints.

 

I agree totally about not making sense that they didn't attach the belt in the center of the ends of the y. It makes no logic why to offset it. Sounds like an easy enough mod to change that around.

 

I spent all day messing with the upgrade bearings trying to get them to not bind.

-Printed new Y bearing mounts.
-Installed new bearings
-Ran them in my drill forever until they were super smooth.
- Even ran 600 grit sandpaper on the rods to polish them up.
-Reamed out the mount holes.

No matter what I do when I install it it binds at the ends and causes wicked vibration.
I think the rods are not straight enough for these brass bushing bearing deals..or the plastic mounts are not precice enough whatever it is I just cannot get it to run smooth. Solo they are super super smooth but when I combine them with two "parallel" rods, bad things just happen near the ends I can't solve.

I got tired of messing with it and put the stock bearings and bearing mounts back on. It moves perfectly free now. a little slop and a little louder but its way better than having that vibration.

 

I wonder if your Y-Axis Rod mounting holes are wider/narrower than the Y-Bearing Mounts when installed? With the stock bearings reinstalled, I don't think you would notice as much.

 

I think they are wider, but i reamed/oblonged the mount holes in the acrylic to hopefully account for that and still couldn't. I think one of my rods isn't very straight or uniform. The stock bearings are working good though so i'm sticking with that for now.

 

I had the same issue. I redesigned the pillow block. I remove 1mm from top and bottom ( no spacers required) and removed the counter sync and in created the size of the holes to allow adjustments. The I tightened them to just snug, then moved them around to get the binding to stop. They are good now.

Sent from my SM-G935V using Tapatalk

 

I mean I basically did that except i ob-longed the acrillic mounting holes instead. Still wouldn't stop binding.

I think i need a new rod one of them must not be straight..it always is binding on the same side even if i swap bearings etc. the stock ones have enough slop in them they are fine though.

 

First let me reply for my horrible grammar in my previous post. I was sitting at an ER typing on my phone. No, I did not upload my re-design to thingiverse. I meant to and never got around to it. I will to do that when I get home and add a link to this post. The bearings slide in firmly. I printed the blocks with ABS with the Scale set to 103. That was the perfect size for me. The model is accurate to the original Specs of having a 15.9mm opening but with ABS and the shrinkage I needed 3% more. I can tell you that the height is correct to not need a spacer. I simply enlarged the mount holes enough to allow a little play. I used the original Screws and they just cover the hole. I still run it a little loose. I also wrote a G code to just run the bed back and forth to the extremes a bunch of times (will run for an hour if you let it) just to help get the bearings broken in and to help get the alignment in. I do not know if that was necessary or not but I did.