Back to back ball bearing arrangement

[newby81]

I have a simple wheel to which I would like to fit 6205-2RSH bearings. The wheel hub diameter does not allow for a larger bearing OD. This bearings does not have the load capacity I need but the wheel hub is 3.5" long. My thought is to fit 4 of these bearings (2 paired on each side).

I feel I should have a thin bearing spacer between each bearing pair but strictly speaking, is this really necessary? Can the bearings simply be pressed in the the wheel up against one another?

 

[TugboatEng]

It's common to put two bearings in a housing without spacers. The clearance in the bearing allows the inner races to butt without preloading the bearing. I can't tell you if 4 will work. You will need to compare the clearances with the total displacement required to butt the 4 bearings together.

Have you considered cylindrical roller bearings for this application?

 

[geesaman.d]

I would consider using angular contact ball bearings that actually can be stacked 'back to back'.

Stacking deep groove ball bearings should work for a pair (think rollerblade wheel) but adding a third or fourth bearing probably won't help at all.

 

[Tmoose]

The load is over 8000 lbs ? What is a 25 mm axle going to think of that ?

A nice pair of tapered roll bearings might be worth considering.

https://www.etrailer.com/faq-popular-wheel-bearings.aspx

Note a rotating hub and stationary shaft require the bearing ODs be ≈.001" Ø interference fit.
A snug slip fit on the axle is OK, and pretty much a requirement to set the bearing clearance.
Ref automotive front wheel bearings for most of the recently expired millenium.