22 Oct
2011
22 Oct
'11
11:15 a.m.
Chuck Guzis wrote:
On 22 Oct 2011 at 11:53, Jules Richardson wrote:
That's an interesting idea!
I wonder how critical it is to fill the gap between the CRT and faceplate
with something, though? For the HP 250 it was a non-functional display, but
on a working screen will there be problems if there's any air trapped in
there (blooming or reflections off the back of the faceplate, for example)
My memory of the HP 250's screen is that the faceplate didn't precisely
follow the contours of the CRT face - the bonding compound varied in
thickness to accommodate this (about 1mm around the CRT face's center and
4mm at the edges).
I don't know how the faceplates are/were normally stuck in place at
assembly - did they apply bonding compound to the front of the CRT and then
press the plate into it, or did they suspend the plate in front of the CRT,
seal around the edges, then pour/inject the bonding compound into the
resulting gap?
cheers
Jules
For the HP 250 I used some resistance wire
connected to a 12V PSU to
cut through the bonding and remove the faceplate. As that was just a
static exhibit machine I just reattached the faceplate by sealing
around the edges though - I'm not sure what best practice is to
'properly' re-seal the entire plate (I'd be particularly worried about
getting air bubbles trapped in there!)
If one wanted real implosion protection, it might be worth
investigating some of the mylar window films made for the purpose of
containing fragments:
http://windowfilmdepot.com/protection.htm