Re: [ARSCLIST] Risk assessment tool--off brands

[JOHN HALL <J.HALL11@xxxxxxxxxxx>]

AUDIOTAPE type 51M was the best and longest lasting tape at that time. The 
backing was triacetape it did not stretch when abused it would break cleanly 
thus spliceing was easy. The backing was coated with an alumnised alloy that 
sputtered on the backing before oxide was applied. The al. application 
reduced printhru. If held up it had a zig zag shape. This was due to the 
sputtering being applied in 1in or so strips. Triacetate does not absorbe 
most liquids. I have about 500 7 1/2 tapes that I recorded in the 50's. All 
of the type 51M is still like new. The 111 tape has for the most part shows 
some oxide loss. AMPEX purchased IRISH in the late 50's. There was another 
tape that was packaged in a blue box. We used it to burnish worn heads. At 
OMEGATAPE we used 51M only. I have 6 14in nab reels of it. Also 2 10 1/2 nab 
reels of 1/7in tape. If you can find some old stock use it. My collection 
has been exposed to temp from -17 to 100+ degrees without being affected. 
So. CA to Bingingham, NY. Now in TN.