Re: Spinthariscopes, scintillators, etc... (fwd)

[Steven Roys <sroys@xxxxxxxx>]

---------- Forwarded message ----------
Date: Fri, 14 Nov 2003 01:18:49 -0800
From: Richard Hull <rhull@xxxxxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Spinthariscopes, scintillators, etc... (fwd)

Thanks Kevin for the update and details on your screen making.

I tend to use 3M #77 spray adhesive and do the same with the sprinkle, embed
and dump routine.  I gotta' at leat try the RTV method that you outlined
though.

Richard Hull


----- Original Message -----
From: "High Voltage list" <hvlist@xxxxxxxxxx>
To: <hvlist@xxxxxxxxxx>
Sent: Thursday, November 13, 2003 1:51 PM
Subject: RE: Spinthariscopes, scintillators, etc... (fwd)


> Original poster: Steven Roys <sroys@xxxxxxxx>
>
>
>
> ---------- Forwarded message ----------
> Date: Thu, 13 Nov 2003 15:32:44 -0600
> From: Daniel Barrett <dbarrett1@xxxxxxxxxxxxx>
> To: High Voltage list <hvlist@xxxxxxxxxx>
> Subject: RE: Spinthariscopes, scintillators, etc... (fwd)
>
> Hello!
> Just an idea- Instead of RTV, you might try Krylon 'Easy Tack'
> repositionable adhesive. It comes in a small $10 spray can from the hobby
> store and essentially makes a sticky-note out of whatever it's sprayed on.
> db
>
>
> -----Original Message-----
> From: High Voltage list [mailto:hvlist@xxxxxxxxxx]
> Sent: Thursday, November 13, 2003 2:53 PM
> To: hvlist@xxxxxxxxxx
> Subject: Re: Spinthariscopes, scintillators, etc... (fwd)
>
>
> Original poster: Steven Roys <sroys@xxxxxxxx>
>
>
>
> ---------- Forwarded message ----------
> Date: Thu, 13 Nov 2003 09:12:03 -0700
> From: June Heidlebaugh <rheidlebaugh@xxxxxxxxxxxxxx>
> To: High Voltage list <hvlist@xxxxxxxxxx>
> Subject: Re: Spinthariscopes, scintillators, etc... (fwd)
>
> Kevin: RTV can be thinned to a liquid with gasoline and it will set up
after
> you paint it on. I use that to soak paper and cloth to make water proof
> diaphragms.
> ---Robert   H-- Original Message -----
> From: "High Voltage list" <hvlist@xxxxxxxxxx>
> To: <hvlist@xxxxxxxxxx>
> Sent: Thursday, November 13, 2003 8:42 AM
> Subject: Re: Spinthariscopes, scintillators, etc... (fwd)
>
>
> > Original poster: Steven Roys <sroys@xxxxxxxx>
> >
> >
> >
> > ---------- Forwarded message ----------
> > Date: Wed, 12 Nov 2003 18:09:12 -0700
> > From: Kevin Christiansen <kevinc@xxxxxxxxxxxxxxxxx>
> > To: hvlist@xxxxxxxxxx
> > Subject: Re: Spinthariscopes, scintillators, etc...
> >
> >
> > Hello again!
> >
> > I just wanted to send a quick follow-up on the phosphor
> > testing that I did a few weeks ago.
> >
> > Since then, I have broken open two black and white monitors
> > (a Sanyo and a Pelco) and tried their picture tube phosphors.
> > They work quite well - better than anything I had tried to
> > date.  The black and white monitor phosphor is definately
> > brighter than the color monitor phosphor.
> >
> > A few days after that, the P-4 phosphor that I ordered from
> > Richard Hull arrived - a little less than a week after I sent
> > him my check. Not too bad for a snail-mail round trip from Utah
> > to Virginia and back.
> >
> > Richard's phosphor came in a zip-lock baggie inside a zip-lock
> > baggie inside a nicely padded shipping envelope - complete with
> > specification sheets on the phosphor, etc.  The baggies contained
> > 5 grams of clean, snow-white, uniform fine powder - much cleaner
> > and much more even than the junk I have been scraping from the
> > picture tubes.  Richard is obviously selling brand-new material.
> > While 5 grams of phosphor does not make a very big pile (about a
> > teaspoon full???), that's a lot of phosphor. I would probably
> > need to scrape 25-50 picture tubes to get that much. Ugh!
> >
> > I quickly made a little spinthariscope screen out of Richard's
> > P-4 and compared it to the stuff from the black and white monitors.
> > The first thing I noticed is that my eyes did not take as
> > long to dark-adjust before I started seeing the scintillations
> > with the P-4 phosphor.  Richard's P-4 is definately brighter than
> > anything I have tried so far - probably 50% to 75% brighter
> > than the B&W monitor phosphors!  Very nice and bright!
> >
> > So, after spending hours scraping phos out of neon tubes, busting
> > up cathode ray tubes and carefully scraping off the phosphors while
> > trying to avoid the razor lead-glass edges, and peering through
> > a magnifyer in the dark, my conclusion is that I should have started
> > with Richard's P-4 phosphors in the first place.  They are brigher,
> > higher quality, non-contaminated, and at 5 grams for $12 (including
> > shipping), a FAR better use of your time!  :-)
> >
> > BTW, for those who are interested, here is my scheme for making
> > a spinthariscope screen out of a 3x5 inch index card.
> >
> > 1) Take a BB-sized glob of RTV and smear it onto the non-lined side
> > of the card with your finger, moving your finger in a circular motion
> > to spread it out so that it makes a very thin, very sticky layer on
> > the card - a circle about 2 inches in diameter.
> >
> > 2) Dump about 1/8 to 1/4 teaspoonfull of phosphor onto the index card
> > and use a small strip of paper to bulldoze it around until it covers
> > all of the RTV.
> >
> > 3) Dump all of the excess phosphor off of the 3x5 card onto a sheet
> > of clean white paper, which can then be folded and used to dump the
> > excess phos back into the phosphor baggy.  Note that MOST of the phos
> > will come off as excess.  It takes a vanishingly small amount of phos
> > to coat a 2 inch circle of RTV.
> >
> > 4) Lay a piece of paper over the phos-coated RTV and press down, to
> > firmly seat the phos in the (very thin) layer of RTV.
> >
> > 5) Wait an hour for the RTV to dry and you are done!  I used RTV
> > because it's VERY sticky, it can be easily spread into very thin layers,
> > and it stays flexible, so that the phos does not flake off when you
> > bend the screen later.
> >
> >
> > That's my phosphor experience. If anybody has any questions, etc.
> > feel free to ask!
> >
> > - Kevin Christiansen
> >
> >
> >
> >
> >
> >
>
>
>
>