Homebrew PCBs

In a message dated 10/19/2005 9:29:20 A.M. Central Daylight Time,  
prashantfordwivedi@... writes:

simple  & cheap method 


Use a fine small drill-press, spindle rotating AT  LEAST 3600 RPM, preferably 
12,000 or more!   Suggest a thin  rubber mat on the drill-press work-surface 
so the board will not slip  around.  Use solid-carbide drill-bits made 
specifically for PCB  drilling.  (all have 0.125" dia. shanks.)  Reconditioned bits 
in boxes  of 50 are available nowadays for 1/4 to 1/3 the "new price".  
 
HSS bits will simply not last for more than a dozen holes in  FR-4 
(fiber-glass epoxy).  Carbide will last for 2000 holes before becoming  dull, but they 
are SO  brittle that they will break LONG before they become  dull, 
particularly if you move the work-piece under the drill-spindle "by  hand".  


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