Axles, just a thought

[garyaodell]

After you drive the car between 25 and 50 miles retorque the axle nuts, notice how much torque you have lost. You may want to retorque again after a couple thousand more miles.

[Chris in CT]

[QUOTE=Joe K;1040312]The question of lubricating machine tapers has been discussed in the machine taper world. See http://www.practicalmachinist.com/vb...tapers-233868/ for a three post entry regarding why or why not to lubricate morse or other machine tapers.

Quick overview: tapers are generally lubricated lightly on even self locking machine tapers primarily to allow disengagement without galling after the work is done.

I'm not so sure I would be that generous. Maybe a small amount of WD40 or other light lubricant? Maybe for no other reason than to exclude water and prevent rust? [Quote]

Hi Joe, I note that the link you posted above contains the opinions of guys like ourselves who are basically hobbyists, and not experts on taper design and application. Permit me to give a loyal and friendly opposing view to the proposition that tapers should be lubricated:

Tapers are designed to be "work holding" apparatus, used to extend or connect shafts in such a way as to maintain full strength of the assembly without introducing any free play, lash, or lost motion into the extended assembly. They need to be clean and dry, and free of rust or any surface contamination in order to function as they were designed. Many are held in their fixed positions by drawbars (or push-nuts in the case of the Model A).
Certain Morse Tapers are only connected by the force of pressing the male taper into the female taper receptacle, relying on a "tang" or rectangular tab at the end of the taper as insurance against rotation if the tool should "hog" into the workpiece, or vibrate loose.

Any form of lubrication will only work to break the integrity of the bond between the male and female parts of the joined taper assembly.

What causes galling is the rotation of the male taper inside of the female portion. Tapers are designed to be separated by direct linear force pulling the male away from the female taper, frequently assisted by a sharp rap to the male end of the taper (or to a loosened drawbar, or to an ejection pin).
There will be no galling to a properly removed taper if it is clean and contamination free.

And...no jokes about male and female tapers, please!

Chris

[Joe K]

Originally Posted by Chris in CT

And...no jokes about male and female tapers, please!
Chris

Funny. You google "lubricate tapers" and you get several web pages on "earcandling."

We mess with machines, they do strange hot things to their ear canals?

As I said, I wouldn't necessarily buy into the Practical Machinist Forum argument and your overview a cogent look.

Confirmed by https://books.google.com/books?id=F9...0taper&f=false which states "don't oil the taper shank of the centers, spindle-adaptor sleeves, and drill-chuck shanks, as a film of oil prevents them from seating properly."

Notice the wording. "A film of oil." I still like the thought of a quick wipe and wipe off with a light oil - if for no other reason than to remove perspiration and the oil from one's skin that one might otherwise leave on the taper.

And in defense of a little lube, there might be something to establishing that "stretch" of the hub radially we discussed earlier, a necessary part of "putting on" a hub. One can't establish a pressure psi without stretching the hub below it's yield point, or possibly above. One imagines that without ANY lubrication that pressure would be highest just under the nut, and in decreasing levels of psi as one approaches the axle full diameter.

This phenomenon reason that a post-driving recommendation is made to "touch up" the hub nut torque. One imagines that the rolling action tends to "even out" pressure across the taper and in doing so, relieves some of the tension under the nut. Tension that is restored in the re-torque.

And a lubricant may help this "evening out" to occur faster? And more positively to it's final tension/pressure?

MANY ways to look at this.

One has to be careful in use of the Internet as a reference source. Just about ANYTHING has been said given enough time and discussion.

Sort of like the mind-exercise considering monkeys randomly typing at a keyboard: eventually, given enough time, they will type ALL known documents?

Including the incorrect ones?

Joe K