Posted by gmharris [71.105.35.169] on Saturday, March 16, 2013 at 20:48:05 :
In Reply to: mis-information on the Forum posted by Mike Stone in Idaho [71.39.211.42] on Saturday, March 16, 2013 at 11:10:12 :
Being the source of that "misinformation", I think I will respond.
I too have heard (about 50 years ago) not to use emery paper on a commutator. I also heard never place a lead/acid battery on a concrete floor, but that is another issue.
Emery is just ground up minerals. While I guess the grit could cause some problem if left on the commutator, I really don't see any difference between using it and some sandpapers which are made from metal oxides. Just clean the commutator before reassembly.
Emery is basically an oxide of certain minerals. The problem with using it to clean commutators is that it can be electrically conductive. Not, that the emery will embed itself in the commutator (Are you spreading mis-information?). Any mineral grit would have the same likelihood of being embedded. I just haven't found the conductivity to be any problem on a 6 or 12 volt generator. I'm sure the caution is warranted for high-voltage machines.
I use emery paper because I like the grits that I have readily available and it works. I have never had a problem and haven't (as yet)heard of anybody else having problems.
As far as needing the armature turned, a good analogy is having the drums turned on your truck. There are varying opinions on that too. But, an armature doesn't always need to be turned. Until recently, I had an armature lathe. But, most people don't have the equipment at home to do the job.
I assume you have never cleaned an armature with emery paper. I have, it's fine. But, different people use different methods. The one I advised is based upon my direct experience. So, turn your drums/armatures, place lead/acid batteries on concrete floors and use emery paper as you like, it's your truck. But, until someone shows me the catastrophic results of using emery paper, I probably just keep doing as I have.
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