Is using a set of scales to measure wheel bearing pre load a good system?

Hi Lex

thanks for info

so the spring reading just needs to be 10-38 more than what ever the 1st reading was?
I asume the N is Nm for the spring? can this be converted to just plain kilograms for a std set of scales?

Regards
GN

N is newtons.
I believe the conversion required is (from onlineconversion.com)
1 newton = 0.1019716213 kilogram-force

10-38N = 1-3.8 kilogram force.

Thanks again Lex

so the 1 - 3.8kg is the amount above the 1st reading as you say so your reading may well be similar to the below system?

This seems to be similar to what i found with google as follows

Torque inner nut to 40-45 ft/lbs.
Rotate hub a couple of turns each way by hand and then re torque to 40-45 ft/lbs.
Then loosed til finger tight, then retension to 10-17 ft/lbs.
Then check pre load with scales on a wheel stud and should be about 6 – 12.5 lbs (2.5 to 5kg) to make the hub rotate.

Does this seem right?

Regards
GN

ps i have had enough of "experts" who cannot remember to tighten bolts or do the whole job properly, which is unfortunate as i would rather not be doing this my self but atleast i know it will not fall to bits up hthe bush because they leave nuts loose etc etc etc

Seems about right but that retorque 40-45 is about 50-60 Nm. Seems tight but I guess it varies for different bearing etc.

mmmmm you may be right on the bit tight, i will keep any eye on this.
The info i found was a bit confusing as at times it was quoting the vehical as a "mini truck" and at other times a "landcruiser" so this is also why i was sus on the specs, but did like the system of measuring to determin pre load.

Many thanks for your help Lex

GN

Hi Pete

You are probably right but have seen a couple of bearings fail and on vehicals that were "supposedly" well maintained, have been told that a bit of play will soon lead to issues on seriously rough corregated roads.

This is why i am wondering if maybe a bit of pre load is a better way to go?

What do you recon?

Regards
GN

Bearings are hardened steel surfaces running together. Play in the bearings allow them the hardened surfaces to hit together. This can eventually lead to failure.
Google "bearing preload" and have a look at some of the bearing manufacturers sites re bearing life and preload.
Heres a sample SKF
There are several more available.

eg Timken

If you are applying a torque on the nut you need to bring into the calculation the length of the spanner otherwise you'll over torque the nut.
The force applied to a lever multiplied by its distance from the lever's fulcrum, the length of the lever arm, is its torque

That's why you use a torque wrench.

Exactly