[78-L] runout spirals

[Michael Biel]

-------- Original Message --------
Subject: Re: [78-L] runout spirals
From: Dan Van Landingham <danvanlandingham at yahoo.com>
Date: Sat, October 09, 2010 2:28 pm
To: 78-L Mail List <78-l at klickitat.78online.com>

> Can you tell me anything about the recording companies that used
> offset mounting holes?I remember George T. Simon,in reference to
> Billy Eckstines earliest recordings in "The Big Bands" from 1966.I
> have one of his on National but I know nothing about the records
> he recorded for DeLuxe in 1944.


I don't understand this question.  By "offset mounting holes" do you
mean the extra driving pin holes in recording discs we were talking
about?  These are only seen in lacquer coated recording discs, not
manufactured shellac or vinyl pressings like National or DeLuxe
(although there are some red vinyl Silvertone 78s with an extra hole in
them for some unknown reason.  I don't understand what you are referring
to in Simon's book.  (There WAS a company in the 1940s which made home
recording discs which also used the brand name National, but I don't
suppose this is what is being discussed unless what you have is a home
recording someone had made of a broadcast on a National disc if what you
have has driving pin holes in it.)    

Mike Biel  mbiel at Ambiel.com



________________________________
From: Milan Milovanovic <milanpmilovanovic4 at gmail.com>
To: 78-L Mail List <78-l at klickitat.78online.com>
Sent: Sat, October 9, 2010 2:07:43 AM
Subject: Re: [78-L] runout spirals

OK, probably there should be an answer to how they did it...

Maybe later, in factory, right before electroplating?


----- Original Message ----- 

From: Royal Pemberton <ampex354 at gmail.com>
>> No, those are called drive pin holes, and served only to
>> prevent slippage of discs while cutting. 

From: "Michael Biel" <mbiel at mbiel.com>
> If you tried cutting a lead out circle with the disc in a driving hole
> you will find that the swing of the eccentric is HUGE!!!!  Plus the
> cutting of eccentric lead outs predates the use of lacquers by well over
> a decade.  And modern lacquers no longer have the driving holes because
> modern lathes use vacuum suction to hold the disc to the turntable.
>
> Mike Biel  mbiel at mbiel.com
>
>
> On Sat, Oct 9, 2010 at 5:05 AM, Milan Milovanovic <
> milanpmilovanovic4 at gmail.com> wrote:
>
>> Are those eccentric grooves were cut by placing lacquer in those 
>> additional
>> holes (1 or 3 of them) used for stabilizing locking blanks onto lathe mat
>> when cutting? You can put cutting needle anywhere then and make just one
>> simple revolution, and voila...
>>
>> Just a thought...
>>
>>