How to properly snug the plain bearing on a running bushing on a horizontal arbor?

[Flynth]

When I got my 3k lbs horizontal knee type milling machine (heckert fw250) it was missing the bronze bushing in the arbor support. Someone replaced it with a non adjustable steel sleeve that contained a cheap ball bearing... Thankfully they used the original nut to retain it.

I've made a new adjustable tapered bronze bearing using the drawings in the manual. I've used it a number of times, but every time I adjusted it I couldn't escape the feeling I might be doing it "wrong" - too tight or too loose.

So I would like to ask here. What is your procedure to adjust the arbor support's plain bearing tightness?

So far I've been doing that:
- initial setup the arbor
- set the spindle gearbox between the gears so I can spin the arbor freely by hand.
- snug the bearing until the shaft just starts to present resistance to rotation!!.
- done

However I'm not sure I've got it set correctly. How do you do it? With an indicator to see runout? Checking temperature by hand? Or somehow else?

Also, does every bronze bearing need oiling channels cut in its circumference or is it sufficient to have a single oil hole and rely on oil getting around the shaft/running bushing via the oil film thickness? The speed will never exceed 300rpm.

Finally what oil do you use for the plain bearing? Way oil?

 

[benmychree]

I would say you are on the right track, in use, there should be little clearance and temperature is a good indicator of clearance, it should get warm, but not hot.