[Boatanchors] Crystal Grinding

[Al Klase]

Dave,

Over the years, I've been reasonably successful grinding crystals with 
3M Wet-or-Dry from the autostore.  400 grit is a good start.

Place the wet paper on a really flat surface, and move the crystal in a 
figure-8 pattern with your finger.  Try to only grind one side.  
Grinding the edges will often restore activity if the crystal fades out 
as you move its frequency.  You can only go upwards.  If you overshoot 
rubbing a bit of solder on the surface can weigh it down and reduce the 
frequency a bit.  That might not be stable in the long run.

Now, some friends of mine advocate etching with ammonium bifioride.  In 
fact I have a bit here that they sent me a couple years ago, bu haven't 
go around tuit.

  There's an article in /Radio & Television/, May 1954 
<https://worldradiohistory.com/Archive-Radio-News/50s/Radio-News-1954-05-R.pdf>, 
page 38 that cover this.

Ammonium bifloride is about $45 a pound on Amazon 
<https://www.amazon.com/Chemsavers-Ammonium-Bifluoride-96-5-500g/dp/B07J5QV4MG/ref=sr_1_1?dchild=1&hvadid=78134057362565&hvbmt=bp&hvdev=c&hvqmt=p&keywords=ammonium+bifluoride&qid=1609864739&sr=8-1&tag=mh0b-20>.

That's all I know,
Al

On 1/5/2021 7:20 AM, David Stinson wrote:
> Some folks have mentioned they grind crystals.
> Never had much success doing so-
> I've killed many a crystal.
>
> If you do have more positive results,
> please detail exactly what you use and
> how you do it.   Old dog seeks new tricks.
>
> TNX DE Dave AB5S
>
>

-- 
Al Klase - N3FRQ
Jersey City, NJ
http://www.skywaves.ar88.net