Re: [ARSCLIST] ET help!

[George Brock-Nannestad <pattac@xxxxxxxx>]

From: Patent Tactics, George Brock-Nannestad


> I have strong, pushy fingers.  A dental tool helped.
> 
> Steve

----- all nailed down, I'd say!

George

> 
> ----- Original Message ----- 
> From: "George Brock-Nannestad" <pattac@xxxxxxxx>
> To: <ARSCLIST@xxxxxxxxxxxx>
> Sent: Wednesday, August 20, 2008 2:31 PM
> Subject: Re: [ARSCLIST] ET help!
> 
> 
> > From: Patent Tactics, George Brock-Nannestad
> >
> >> I recently did a job where I was able to create tracking through with
> >> plastic clay.
> >>
> >> Steve Smolian
> >
> > ----- wow! Was that a lacquer record? The layer is awfully thin. My main
> > use
> > of plastic clay has been to exclude oxygen on cracks cemented with
> cyano-
> > acrylate (shellac-base record), because it can be removed from the
> grooves
> > afterwards without damaging them.
> >
> > Kind regards,
> >
> >
> > George
> >
> >>
> >> ----- Original Message ----- 
> >> From: "George Brock-Nannestad" <pattac@xxxxxxxx>
> >> To: <ARSCLIST@xxxxxxxxxxxx>
> >> Sent: Wednesday, August 20, 2008 12:16 PM
> >> Subject: Re: [ARSCLIST] ET help!
> >>
> >>
> >> > From: Patent Tactics, George Brock-Nannestad
> >> >
> >> > Matt Sohn recalled:
> >> >
> >> >
> >> >> >> I've a pretty good hand at transferring ETs, but the
> >> >> >> cracks in the lacquer
> >> >> >> make this one a real challenge.  Is there any way of
> >> >> >> restoring these
> >> >> >> grooves?  I thought of prying off some of the lacquer in
> >> >> >> chunks to glue back
> >> >> >> in place, but I'm not sure the grooves would line up even
> >> >> >> then.
> >> >>
> >> >>
> >> >> I recall talking to someone a long time ago who said he used
> >> >> clear nail polish to fill in the cracks. I don't remember
> >> >> who it was or how exactly he did it, or what possible damage
> >> >> to the disc might result from such a procedure, but I
> >> >> thought I'd pass it along..
> >> >
> >> > ----- I would not recommend nail polish. While the softening agent is
> >> nice
> >> > and makes for a tough coat, the solvents are the same as for
> cellulose
> >> > nitrate - because nail polish is mostly cellulose nitrate! This means
> >> that
> >> > you would eat into the edges of the lacquer layer. This makes for 
> >> > better
> >> > bonding but also rounded curves. And you still have to cut a groove
> to
> >> > carry
> >> > the stylus from where it leaves lacquer to the correct place at the 
> >> > other
> >> > end
> >> > of the gap. And, as I said, nail polish is tough!
> >> >
> >> > I have had good results with waxes (low-melting micro-waxes). BUT, 
> >> > waxes
> >> > usually implies heating and applying it in liquid form. On an
> aluminum
> >> > base
> >> > the heat of solidification will be distributed to other areas,
> causing
> >> > differential heating, and who knows what damage that might cause. On 
> >> > glass
> >> > it
> >> > is safer. Using a solvent for the wax that is not also a solvent for 
> >> > the
> >> > cellulose nitrate (paraffin would work for some waxes) would permit
> >> > application of the liquid and then wait for the solvent to evaporate.
> >> You
> >> > need to cut grooves under the microscope to connect correctly, but
> that
> >> is
> >> > simple - the worst crack I have come across was 3.5 millimeters 
> >> > (narrowing
> >> > to
> >> > zero over 40 mm, and a ruler to support the scriber was quite 
> >> > sufficient.
> >> > And
> >> > the wax is very easy to cut.
> >> >
> >> > But you have to remember that the shrunken lacquer also has a
> shrunken
> >> > time-
> >> > base, so it is not just a question of removing the clicks of silence,
> >> > but
> >> > of
> >> > stretching time, perhaps 5%, perhaps less, of the sound you do
> obtain.
> >> >
> >> > Again, like Eric said, it takes experience, and whose lacquer record
> is
> >> to
> >> > suffer?
> >> >
> >> > Kind regards,
> >> >
> >> >
> >> > George
> >> >
> >