On Jul 31, 2022, at 9:21 PM, [email protected] wrote:

Mr. Google says: Ammonium bifluoride will react with water to form hydrofluoric acid.

Wayne

WB4OGM

-----Original Message-----
From: Bob kb8tq <[email protected]>
To: Mike Feher <[email protected]>
Cc: Brooke Clarke <[email protected]>; Milsurplus <[email protected]>
Sent: Sun, Jul 31, 2022 9:48 pm
Subject: Re: [Milsurplus] Crystal History Book and tips on etching

Hi

If you are etching crystals in a modern crystal plant, the

“go to” is a solution of ammonium bifluoride. It’s much easier

to deal with in the required concentrations than HF.

Bob 

On Jul 31, 2022, at 5:53 PM, Mike Feher <[email protected]> wrote:

While in college I got a container of HF from our chemistry lab. It came in a plastic container as it would eat glass. I did etch numerous crystals with it. While I was not aware of the hazards, I did use some caution in using the stuff. 73 – Mike 

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Brooke Clarke via Milsurplus
Sent: Sunday, July 31, 2022 5:31 PM
To: [email protected]
Subject: Re: [Milsurplus] Crystal History Book and tips on etching

 

Hi Dennis:

 

My reading of patent 2479286 is that after grinding, quartz crystals have micro cracks that propagate with aging and temperature cycling.  By using an HF etch the cracks are removed thus stabilizing the crystal for both aging and temperature (See Fig 6, 7 & 8 in patent).  The patent also includes a slide rule design (Fig 10) which, for a given frequency change and cut, tells you the etch time.

https://prc68.com/I/Xtal.shtml#Bliley

 

PS I worked in microwave semiconductors and they used HF.  Extremely dangerous stuff since it attacks humans in such a way that they are not aware of it.

https://en.wikipedia.org/wiki/Hydrofluoric_acid#Health_and_safety

 

--

Have Fun,

 

Brooke Clarke

https://www.PRC68.com

axioms:

1. The extent to which you can fix or improve something will be limited by how well you understand how it works.

2. Everybody, with no exceptions, holds false beliefs.

 

______________________________________________________________

Milsurplus mailing list

Home: http://mailman.qth.net/mailman/listinfo/milsurplus

Help: http://mailman.qth.net/mmfaq.htm

Post: mailto:[email protected]

 

This list hosted by: http://www.qsl.net

Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html