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

[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
>
>
>
>
>
>