Refurbishing a Warco RF 25 mill drill- spindle bearings

[Trevorc]

Hello , i have a mill drill ex China marketed in UK by Warco as RF25, about 15 plus years old.
For past year or so there has been an increasing noise from what i suspected was the spindle bearings.
Have taken the plunge and stripped down the spindle and removed the old tapered roller bearings( they don't seem too bad!!) Whilst i await delivery of the new ones i need to understand how to fit them correctly.
I understand that they need to be under  some level of axial loading once installed. My question is how much axial loading? Just enough to prevent axial movement or more?
Any advice greatly appreciated and any general comments on refurbishing the RF 25.
Thank you
Trevorc

[Stuart]

John Stevenson RIP
Said to me just take up the end float use a dti if possible


That being said you will many different views/advice/WHY as a squirrel has fleas 😳


When I did my sx3 I did as John recommendation and ran the spindle in the lathe to bed it in checking the temp and varying the speed for about 30 mins to 1 hour I then found I needed just a further nip , ran the lathe test again to be sure

It’s been a good few years but it just gets warm at top speed after extended run time ,but I suspect that is heat from the tool migrating up to the spindle

Just in the process of doing the same job to my other mill the cost of the bearings £300 , glad it’s not a Swiss made job else I would be looking at £5K 😱

Have fun , take care and be safe

Stuart

[Jasonb]

Same here, when my X3 arrived the spindle had play, I just nipped up the nuts until it felt right and I could not measure any wobble. Have not had to touch it in the past 12 years since then. Ditto the lathe when I changed the bearings in that.

[Neil-Lickfold]

The 1st sign of being over loaded is a temp increase that you will feel on  the housing. Using a DTI and looking for end float and radial movement. Tighten until all the movement has just gone away.
They can be easily over tightened , and will be damaged if left on the loose side.

[Admiral_dk]

They are in a way similar to conical roller bearings used in wheel axels on cars and steering heads on motorcycles - in both instances there are some very specific torque requirements.

On cars you usually set the torque wrench to the specified torque and then tighten the nut till the wrench clicks.

On bikes steering head you start by doing just the same so the bearings are pulled fully into place, but after this you loosen the nut some 10-20 degrees (specified in the manual) and then tighten the counter nut.
This way you get no play and a very low friction steering - I would guess a similar approach would work nicely here if there are any specifications available ….