PDA

View Full Version : Should my Z axis have a little play in it?



Philly
27-04-2011, 01:59 PM
This is a strange one, but Im not sure if its normal. If I apply a little pressure to the bottom of the Z axis and lift it up it will move a few mm. Is this normal, could it be the couplers?

Just wondering as my carvings are developing lines across them from where the Z axis isnt returning back to the same spot.

Cheers, Phil

birchy
27-04-2011, 08:40 PM
That's a LOT of play. Something needs tightening.

blackburn mark
27-04-2011, 10:24 PM
This is a strange one, but Im not sure if its normal. If I apply a little pressure to the bottom of the Z axis and lift it up it will move a few mm. Is this normal, could it be the couplers?

Just wondering as my carvings are developing lines across them from where the Z axis isnt returning back to the same spot.

if you bought 1605 screws nuts and bearings from china you may need to add a spacer between the angular contact bearings (all of them) they are mounted as if they are matched pairs that only need pressing together however they are not matched and no matter how much you press them together they do not pinch.

Philly
28-04-2011, 04:16 PM
Right, I've managed to check in the daylight and it appears the coupler is one of those springy type ones and its allowing the whole z axis to move. Going to order a normal coupler, anyone have any recommendations?

Thanks

ptjw7uk
28-04-2011, 04:22 PM
Somethings wrong with the setup as the coupler is there to protect the motor bearings.
Sounds as if the end bearing setup is all wrong, it should turn but have little or no play.
Peter

AdCNC
28-04-2011, 06:24 PM
Show us a photo of your setup buddy

Philly
28-04-2011, 06:40 PM
Show us a photo of your setup buddy


Will do, charging camera now.

Gary
29-04-2011, 05:28 AM
If you are using the coupling to support the load then it is all wrong, the coupling in only used to transfer the torque from the motor to the screw and absorb any radial movement.
They are not desigend to take any axial or radial load, also if you get a solid type then you will also have problems with movement becasue the motor will have a spring washer in the back and this will give about 0.5-1MM of movement.
You need to use a bearing arrangement to take any radial or axial loadings and without this the system will fail.



Right, I've managed to check in the daylight and it appears the coupler is one of those springy type ones and its allowing the whole z axis to move. Going to order a normal coupler, anyone have any recommendations?

Thanks