HP CRT mould update

[Vintage Computer Festival]

On Sun, 17 Apr 2005, Jules Richardson wrote:

> I've just removed the faceplate on the CRT for an HP 250 that was
> suffering from the dreaded mould. Used a bit of resistance wire as
> someone here had suggested, and it was a remarkably easy job.  Took
> about ten mins to make it all the way across the CRT (although I was
> only running from a 10V DC supply - I expect there's a lot of scope for
> increasing the voltage without risk of damaging the CRT)
>
> The sealant stuff pretty much just peels straight off the front of the
> CRT / rear of the faceplate once the two are separated. A knife blade,
> not water, and washing detergent shifted the rest and cleaned everything
> up.

Jules,

Thanks for the info.  Did you save any of the affected scraps to have
analyzed by a biologist or something?  I don't know if you know anyone
over there who would do it for cheap or free but I know someone over here
who can.

Are you certain it was a mold eating at the sealant or was it, as someone
else put forth, a simple delaminating affect which caused the round spots
to appear when the faceplate was pried away from the CRT?

Until some of this gets actually analyzed and confirmed as a mold or
fungus then I won't fully rely that it in fact is such.

> I'm not sure about trying to re-seal it; that could go horribly wrong
> and leave air bubbles trapped in there. Not even sure what stuff to use.
> Padding the faceplace out as necessary right at the edges (where it
> won't be visible when everything's back together) is probably the best
> course of action and it'll look as good as new when back together.

If you don't introduce some sort of filler you might have a shadow or
annoying opitcal affect.  Possibly.

> Next interesting task will be getting the paint off the 250's console
> desk though - seems like when they were scrapped someone just went
> around with a spray-can and put big X's on anything that was being
> disposed of...

Gasoline (or petrol as you might want to call it :) is supposed to be able
to dissolve spraypaint without affecting the underlying paint.  Also, a
naptha solvent should work but only if used carefully (don't apply
directly, apply to a cloth, and work it very lightly and slowly).

-- 

Sellam Ismail                                        Vintage Computer Festival
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