Originally Posted by
prathmann
It says to consult the crank manufacturer's instructions - not necessarily to follow them blindly.
It does not appear that you have read my previous posts. Please do if you wish to engage with me further in this discussion.
Never have I implied, much less stated, that one should follow manufacturer's instructions "blindly." You are arguing against something I never said, and if you continue to do so, I will ignore your posts. My point has consistently been that if you choose not to follow manufacturers' instructions, you had better know what the consequences are.
Originally Posted by
prathmann
Personally, I give preference to those who can give a coherent physical explanation of their viewpoint.
I gave you a coherent (if brief) physical explanation of my viewpoint. But you chose to ignore that. So again, why would it possibly matter to Phil Wood whether cranks from other manufacturers go on their spindles dry or lubed? Their spindles are many times harder than any aluminum crank, and as I said, won't be the least affected by lubrication or not. It's the crankarm that's going to be damaged or compromised by installation procedure. Not their spindle.
But anyway, there's no shortage of coherent physical explanations. How do you decide? A louder voice, or a more complicated or detailed explanation doesn't necessarily correlate to its being more authoritative. The basis of the explanation also matters.
These are a few that I happen to have instant access to. Submitted without commentary. If you have issues with any of them, or wish to know the basis of their explanations, I suggest you take it up with the sources themselves. They might actually respond.
Sutherland's: "The axle end and the hole in the crank must be clean and dry. Do not use oil, grease, or an anti-sieze compound. The tapered square system depends on the crank coming up firmly on the axle.
Any lubrication will cause the arm to go on too far in tightening or to float on the spindle. Either way the arm will be ruined. Grease or anti-seize compound may be used on the threads of the crank bolt." (6th edition, rev. 1995, p. 2-4) [emphasis in original]
Barnett's: "...prepare the arm for installation by cleaning the mating surfaces in the spindle and arm with acetone or alcohol. The purpose of this is to remove any traces of lubricant. Since these two pieces are held together by friction, grease or oil may enable the arm to go on further (not necessarily a good idea.) Further is not more secure if arrived at by lubrication. Crank manufacturers are unanimous in recommending against spindle lubrication of the spindle when mounting the arm. Arguments to the contrary have been voiced,
but never lubricate the spindle flats! If there is a concern about preventing corrosion or about contaminants getting in the gaps between the spindle flats and the hole flats in the arm, then treat the mating surfaces with Loctite 222 or 242.... The Loctite will seal the surfaces from moisture and dirt, reduce creaking problems, will not cause the arms to be less secure, and will allow arm removal with normal effort." (ch. 20, p. 11) [emphasis in original]
JIS: "Affirm that there is no adhesion of foreign matters and the like at the inner wall of corner hole of right crank and right corner face of bracket axle, and fit by coinciding the right crank corner hole with the bracket axle corner face." (JIS 1993, D 9311, table 4, panel 18)
The JIS spec is based on a test of the above assembly. It requires a load of 1200N being applied 1,000,000 times, 60 times per minute, (almost 278 continuous hours of testing) after which "...there shall not occur fissures or breakages in the crank, nor slackening in the fixing part of the crank and the crank spindle." (JIS 1993, D 9415, sec. 4-5)
All of the above recommend accurate torque on the crank bolt. Which (may I say again is Brandt's main point) is really the most important factor in the process. The missing point for most people is that
lubrication on the spindle requires torque settings to be lower to compensate for the decrease in friction between the parts.