Bushings binding on rods

[Gencab 19]

On my Ultimaker Original Plus I have been fighting this odd binding issue. When the X and Y along that run along the belts are aligned (I do this very meticulously)  the bushings bind against the right side rod only moving away from the front. When motion is applied in towards the front of the unit no binding is present and is very smooth. If I clean the rod after a print the binding is less present but you can slightly feel it. After a print the binding is back.

 

So what im trying to determine is

- do the bushings need to be replaced?

- did the rods get bent?

-do I need to apply any kind of lube to the rods? Seems like this would only mask the problem.

 

You help is very appreciated.

Thanks

[geert_2 558]

I don't know about the UMO, but on the UM2 the bushings definitely need oil. Oil does not only reduce friction, thus it prevents metal on metal wear, but it also allows trapped dust to be removed, thereby again reducing wear.

 

Officially the UM2 rods need thin sewing machine oil. But I found that this dries too quickly (may depend on oil brand and composition), so now I use a high grade hydraulic oil, also used in industrial applications like hydraulic test benches, tractors, bulldozers,... This oil does not dry out at all, it lubricates well, and it contains anti-corrosion and anti-foam additives. Not sure if this is the best solution, but it works for me. One of the other reasons why I use this, is because I have a lot of spare of it.

 

Concerning bent rods: maybe you could see if that shows up if you print a thin test layer of 0.1mm? It should cause a wave-pattern in the thickness, of the same distace as the circumference of the rods?

 

[Gencab 19]

 

7 hours ago, geert_2 said:

I don't know about the UMO, but on the UM2 the bushings definitely need oil. Oil does not only reduce friction, thus it prevents metal on metal wear, but it also allows trapped dust to be removed, thereby again reducing wear.

 

Officially the UM2 rods need thin sewing machine oil. But I found that this dries too quickly (may depend on oil brand and composition), so now I use a high grade hydraulic oil, also used in industrial applications like hydraulic test benches, tractors, bulldozers,... This oil does not dry out at all, it lubricates well, and it contains anti-corrosion and anti-foam additives. Not sure if this is the best solution, but it works for me. One of the other reasons why I use this, is because I have a lot of spare of it.

 

Concerning bent rods: maybe you could see if that shows up if you print a thin test layer of 0.1mm? It should cause a wave-pattern in the thickness, of the same distace as the circumference of the rods?

 

 

 

The UMO, UMO+, UM2 and so on share the same motion components only the arrangement is slightly different depending on the model so in that regard the problems and solutions would be very similar. I think ill give hydraulic oil a shot and see what that produces. Im trying to track down what is causing a layer shift between 7 and 8 mm only on X axis no matter the model. I suspect this is a factor but I cant seem to figure out what the catalyst is for a layer shift to happen several millimeters in to a print.