Re: [ARSCLIST] Ampex 456 and Shamrock 041 Manufacturing Specs?

[Michael Biel <mbiel@xxxxxxxxx>]

Sarah Norris wrote:
> Hello,
>  
> I'm looking for any manufacturing information available about Ampex 456 and Shamrock 041 tape.  Anything would help, including manufacturing dates and anything known about materials or formulations used.  All information and references are much appreciated.
>  
> Thanks,
> Sarah Norris
>
>
>   
These were made in the former Orradio Irish Tape factory in Opelika, 
Alabama which Ampex bought in the early 60s.  Shamrock 041 is 1 mil, 031 
is 1.5  mil, and 051 is 1/2 mil.  Shamrock, also found in Radio Shack 
Concertape boxes among many other brands, came in many different 
varieties.  You could find brown oxide, standard non-backcoated black 
oxide, polished black oxide with carbon backcoating, and brown oxide 
with lubricated graphite backcoating that was normally used for winding 
continuous loop tape cartridges.  When the  boxes were shrinkwraped you 
had no way of knowing what you would get.  I used to buy shrinkwrapped 
Concertape in discounted quantities of 10, and never did I get ten of 
the same type!  In the early 70s I used to go to the main mailorder 
warehouse of Olson Electronics in Chicago which let me go thru the 
factory cartons of  un-shrinkwrapped Shamrock 041 and pick which reels I 
wanted if I bought them in multiples of 50.  Types were mixed in every 
one of those factory cartons of 50. Unfortunately I went for the quality 
stuff -- black oxide carbon backcoated.  DAMN.  So thre is nothing 
consistant about the 0X1 series.

Mike Biel  mbiel@xxxxxxxxx