Re: ATM 10" help - TDE?

["Tyrone Steele" <atm@pivotmusic.com>]

I am using my tester, of course.
The blind test has, regardless of propoganda, assisted me during the
polishing stage in determining the state of the mirror's edge.


----- Original Message -----
From: "Richard Schwartz" <richas@earthlink.net>
To: <atm@shore.net>
Sent: Monday, September 30, 2002 12:31 PM
Subject: Re: ATM 10" help - TDE?


>
> NO.   The blind test is intended for use during grinding.
>
> If you are figuring, you should use your foucault tester.  The errors you
> are dealing with at this stage are too small to be seen with the blind
test.
>
> . . . Richard
>
> ----- Original Message -----
> From: "Tyrone Steele" <atm@pivotmusic.com>
> To: "ATM" <atm@shore.net>
> Sent: Monday, September 30, 2002 7:08 AM
> Subject: Re: ATM 10" help - TDE?
>
>
> >
> > I performed the "blind Test" as described by Richard Schwartz  And it's
> not
> > TDE!
> > In fact, after looking at the mirror surface using the blind test
(should
> be
> > renamed to the "venecian blind test" for accuracy) I found that the
shape
> is
> > quite near parablola.
> > So, it seems to me that the folly of using a focault test to determine
the
> > edge shape (whether TDE, TUE or otherwise) is that both shapes are
> > interpreted alike.
> > I had recieved so many different points of view and alternating
> > determinations from folks about those tester photos I posted (thinking
it
> > was a TDE), that it was becoming frustrating.
> > So just for the record the blind test can be used effectively just prior
> to
> > the figuring stage, especially when in doubt of the outer edge of the
> > mirror, as well as just prior to polishing.
> >
> > I will be moving on to the figuring stage next.
> >
> >
> >
> > This is the follow of
> > ----- Original Message -----
> > From: Richard Schwartz
> > To: Tyrone Steele
> > Sent: Friday, September 27, 2002 8:20 AM
> > Subject: Re: ATM 10" help - TDE?
> >
> >
> > Try www.megspace.com/science/sfe/i_fa_art.html.
> >
> > Because this test is done at a grazing angle, you can do it during
> grinding
> > of the last two grades of grit.  In the example above, it should be
> obvious
> > that there is a serious turned down edge.   This is the blind test.
> >
> > For the red-out test, ask Bob May.  He has some ideas on it over and
above
> > mine.   I have been doing the red out test for a long time, but was very
> > surprized a couple years ago to see Carl Zambuto doing it.  He was kind
of
> > sneaky, just briefly holding a mirror up to the light and glancing at it
> > edgewise...   I think I alone knew what he was doing.  The red-out test
is
> > described in the attached file. (associated pictures not included)
> >
> > . . . Richard
> >
> >
> > ----- Original Message -----
> > From: "Tyrone Steele" <atm@pivotmusic.com>
> > To: "Richard Ozer" <rozer@ois-online.com>; "Richard Schwartz"
> > <richas@earthlink.net>; <atm@shore.net>
> > Sent: Wednesday, September 25, 2002 8:17 PM
> > Subject: Re: ATM 10" help - TDE?
> >
> >
> > >
> > > Agreed.
> > > I have no idea what you're talking about.
> > > If you mean the sharpie test, yes that was done many times.
> > > What the heck is a 'blind test'.
> > > Is that sarcasm?
> > >
> > > ----- Original Message -----
> > > From: "Richard Ozer" <rozer@ois-online.com>
> > > To: "Richard Schwartz" <richas@earthlink.net>; <atm@shore.net>
> > > Sent: Wednesday, September 25, 2002 2:58 PM
> > > Subject: Re: ATM 10" help - TDE?
> > >
> > >
> > > >
> > > > Can you elaborate on these?
> > > >
> > > > RO
> > > >
> > > > ----- Original Message -----
> > > > From: "Richard Schwartz" <richas@earthlink.net>
> > > > To: <atm@shore.net>
> > > > Sent: Wednesday, September 25, 2002 12:22 PM
> > > > Subject: Re: ATM 10" help - TDE?
> > > >
> > > >
> > > > >
> > > > > How did it look under the red-out test before you started
polishing?
> > > How
> > > > > did it look under the blind test?   Those provide a good check of
> the
> > > > > quality of fine grinding, but I betcha you didn't do any such
thing!
> > > > >
> > > > > . . . Richard
> > > > >
> > > >
> > >
> > >
> >
> >
>