View Single Post
Old 07-19-18, 10:13 AM
nfmisso's Avatar
Join Date: Mar 2011
Location: San Jose, CA
Posts: 2,991

Bikes: 1980s and 1990s steel: CyclePro, Nishiki, Schwinn, SR, Trek........

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 383 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
Originally Posted by FBOATSB View Post
OK, before I get more confused, when we say a certain ball bearing is "magnetic", don't we mean that said ball bearing is composed of "ferromagnetic" material, for example steel, but may not necessarily be "magnetized"? I used to use a magnet to position new balls into their corresponding cups until I noticed the new balls were becoming magnetized by my doing so and thus sticking to each other. Hopefully only temporarily, but still I know of a great deal of lubricated machinery having a magnet placed inside in a strategic location, usually a drain plug, to attract and hold any ferromagnetic grit or filings so as to keep it all out of the bearings as much as possible. If magnetizing new ball bearings might attract steel grit to them I thought it prudent not to. If just they lose their magnetic fields guickly, maybe no big deal. I still use the magnet to quickly pull out old balls for disposal though.
The balls will loose their temporary magnetism quickly, faster in the neighborhood of other temporarily magnetized balls and when exposed to mechanical force (bearing preload and loads for example).
nfmisso is offline