Re: [Phono-L] Edison Bearing

2013-01-29 Thread Don Mayer
I tried making sintered bronze bearings when I started machining, maybe 35 
years ago now. Possibly because of less-than-adequate machining technique, I 
found that sintered bronze produced greater friction on the mandrel shaft than 
did plain brass. I consequently continue to use brass and have the ritual of 
oiling to contend with, but do that happily in exchange for a mandrel which 
rotates with less effort, important when motors have lost some of their oomph 
due to worn gear shaft pinions, gear teeth and the like. I may have thought at 
the time that oiling the mandrel shaft was part of the cachet of acoustic 
phonograph technology. I would enjoy hearing if others with better technique 
have a better experience with sintered bronze than I did.

Regards,

Don Mayer

It is important to note the difference between bronze bushings and 
 sintered bronze bushings.  The former require regular lubrication as does 
 any other plain bearing.  But the sintering process produces a material that 
 is porous and will hold lubricant in its pores which significantly reduces 
 the need for regular oiling.  Here's a description of proper and improper 
 machining of sintered bronze:
 
 http://www.lm-tarbell.com/machining_sintered_bronze.htm
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Re: [Phono-L] Edison Bearing

2013-01-29 Thread Rich
There are specific cutter angle recommendations for machining stintered 
bronze and I do not have them readily at hand. Having this info is a 
requirement for DIY bearings as you are actually attempting to cleanly 
cut each very small ball without smearing it.


On 01/29/2013 03:15 PM, Don Mayer wrote:

I tried making sintered bronze bearings when I started machining, maybe 35 years ago now. 
Possibly because of less-than-adequate machining technique, I found that sintered bronze 
produced greater friction on the mandrel shaft than did plain brass. I consequently 
continue to use brass and have the ritual of oiling to contend with, but do that happily 
in exchange for a mandrel which rotates with less effort, important when motors have lost 
some of their oomph due to worn gear shaft pinions, gear teeth and the like. 
I may have thought at the time that oiling the mandrel shaft was part of the cachet of 
acoustic phonograph technology. I would enjoy hearing if others with better technique 
have a better experience with sintered bronze than I did.

Regards,

Don Mayer


It is important to note the difference between bronze bushings and
sintered bronze bushings.  The former require regular lubrication as does
any other plain bearing.  But the sintering process produces a material that
is porous and will hold lubricant in its pores which significantly reduces
the need for regular oiling.  Here's a description of proper and improper
machining of sintered bronze:

http://www.lm-tarbell.com/machining_sintered_bronze.htm

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[Phono-L] ron haring

2013-01-29 Thread Zonophone2006
hi
sorry all
ron can you email me privately
i lost your email address
thanks
rob
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