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Growing Rochelle Salt crystals?? - Printable Version

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Growing Rochelle Salt crystals?? - Guest - 02-23-2009

Hi ya Syl, hopin' you might answer this one, or anyone else that has any experience with or has experimented with this.
Can you make a Rochelle Salt crystal? Sure you can, they are one of the most common crystals for the hobbyists that grow crystals. I’ve grown them a couple of times in the past, but there are problems with using them. They are very fragile, not hard like a ceramic or silicon crystal. I’ve never found a way of cutting them; they just crumble with every effort that I have tried. Would love to learn how they were cut in the factories like at C.T. S. Knights when they were in business here in Sandwich, IL.
And why grow Rochelle salt crystals, well the experienced old timers know that they put out the highest voltage of any of the crystals but for the new comers like me they will output 3v.
So, I’d like to here any stories about your try at it.

Denny Graham
Sandwich, IL


Re: Growing Rochelle Salt crystals?? - FStephenMasek - 02-23-2009

Denny, you might want to contact Gib at West Tech, as he told me something about obtaining the crystals, or a source for them, or some such thing.


Re: Growing Rochelle Salt crystals?? - Syl - 02-23-2009

Darn, I typed a long post and it vanished. Here's a short one, too lazy to type it all again...

In short, you can't., other than growing your own for curiosity.

You can use cheap crystal mikes elements salvaged out of 1$ a pop mikes from a well known online electronics surplus
store. Or find donor cartridges with encapsulated crystals.

Syl


Re: Growing Rochelle Salt crystals?? - Guest - 02-24-2009

Well Syl, I guess that's, that. but it sure would be a kick if someone could figure out how to grow/cut/acquire crystals. And boy do I love a challange. I did here from someone who knew someone that worked at C.T.S Knights and he said they would cut the soft crystals with a thread that was weighted on each end. Not much to go on but it's a start. When I worked at Fermilab we cut silicon with a diamond disk flooded with a coolant, a slow process. Of course you can't use a coolant with the Rochelle crystals so we tried it dry and even with the lightest pressure they would just crumble. Gotta think about that thread a bit. I'm would think that an electrical connection could be made with a dot of conductive epoxy, I don't know any other way one could do it in a home shop, that is if he could get a crystal properly cut.
And would those "1$ a pop mikes" be ceramic with maybe 1v or less output?

Is Gib one of the owners FStephen? I thought West tech was in the business of rebuilding cartridges, I would be very surprised if they were giving away their secrets. I've found that most of the guys that have developed methods for rebuilding old radio or phono parts are kind of secretive about it, that is except Syl, he's given freely of his work. Even with his instruction I'll bet 95% of the guys that try it end up failing. That looks like some very delicate work.
Denny Graham
Sandwich, IL