[ARC5] Crystals in WWII

[Richard Knoppow]

----- Original Message ----- 
From: "Kenneth G. Gordon" <kgordon2006 at frontier.com>
To: "D C _Mac_ Macdonald" <k2gkk at hotmail.com>; "Arc5 mail 
list" <arc5 at mailman.qth.net>
Sent: Friday, March 15, 2013 8:54 AM
Subject: Re: [ARC5] Crystals in WWII


> On 15 Mar 2013 at 8:53, D C _Mac_ Macdonald wrote:
>
>>
>> "HF" ?
>
> Hydrogen Flouride = Hydroflouric Acid.
>
> Very highly dangerous stuff as it can be absorbed through 
> the skin and will
> attack bone under the flesh. It will also burn the flesh.
>
> It is the only acid that will dissolve glass....and 
> quartz...so it must be stored in
> special plastic bottles.
>
> It is, or was, used to "etch" both glass for artistic 
> glassware, and quartz for
> crystals.
>
> Bliley discovered and used it first for crystals. It has 
> been used for centuries
> to etch designs into glassware, like vases and drinking 
> glasses.
>
> As I said, surprising as it may seem, "Whink" has a bit of 
> HF in it.
>
> Ken W7EKB

     One can get a glass etching cream from places that sell 
hobby supplies.  I got some on line. It probably has 
hydrofluoric acid in it but I don't know for certain.  I 
originally got it to make ground glass for cameras.  It 
works for that but I haven't mastered the technique and get 
rather uneven surfaces.  I've also used it to etch the bulbs 
of pilot lamps to get some diffusion. This will improve the 
illumination of some dials and illuminated meters.
     This cream is quite mild so short time contact with it 
does not cause injury, however strong hydrofluoric acid is 
extremely hazardous, it causes severe burns which heal very 
slowly.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com