Thrust bearing for ZeroG Hydra with Stepperonline 42*48 Steppers on Z axis

This is used with Stepperonline 42x48 stepper motor model 17HE19-2004S.

Used with Uxcell 9x20x7 Thrust Bearings purchased from Amazon. Tried another brand from Aliexpress and they were the same dimensions.  

This was printed in ASA, Part cooling was used at 40% as it is a small part and that helped keep it stable.  The shaft may need cleaned out. A 5.1mm drill bit was used . If you do not have that a 13/64 bit is close enough.  The parts fit together tightly a spot of acetone was added to mine to make sure it does not move. Plus some light sanding to clean up any imperfections. Yours might print better since this was printed using a .6mm nozzle. 

This enabled using thrust bearings to keep  bed and other parts weight off the 3 stepper motors. These are a bit more robust than 42x34 steppers but still are not really rated for axial loads.

The bearings used have a larger opening on one side. Place that side to the bottom.  They were lubricated with a lithium based grease.  Finally eliminated a faint banding that was showing up on prints. Added POM nuts first and they did not help so tried this next

Used rigid couplers on the printer. This was the only one available to display.

Was asked on another site why I think the printer needs the axial load supported since the weight is divided among 3 stepper motors. If you go to this website 

https://www.omc-stepperonline.com/e-series-nema-17-bipolar-55ncm-77-88oz-in-2a-42x48mm-4-wires-w-1m-cable-connector-17he19-2004s

Then go to downloads and get the full datasheet you will find the maximum allowed dynamic axial load for this stepper motor is 10Nf. Converted to lbf that works out to about 2.24 lb of dynamic load per motor.  On mine the 10mm thick cast bed plus the z screws, bed heater, top magnet, Pei removable build plate and associated hardware for the Hydra setup exceeds this.

So I felt reducing the weight would be worthwhile. If nothing else to extend stepper motor lifespan. It removing the faint lines showing up on prints was a plus.

Could not find axial load ratings for the 3-17HS15-1504S-X1 stepper motor recommended  but the one sold by Fabreeko LDO-42STH40-1684L470E also has a rated load of 10N 

https://ldomotors.com/products/show/42mm-hybrid-stepper-series.

I chose to buy 5 of the larger since it was less than buying 2 of the larger and 3 of the smaller.