Cat litter absorbent crystals.

mldee (Mike) · #1 26-02-2010, 02:18 PM

I was roaming through Coles this morning and noticed bags of "New" cat-litter absorbent crystal, with the labels saying they contained silica gel. This stuff is not the clay or paper stuff normally sold for cat poo use.

The texture of the crystals was very similar to normal silica gel desiccant and colour (bags were transparent) was mix of clear and blue crystals about the size and consistency of rock salt.

Good price; 2Kg for about $5 if I recall. Cheap and also convenient to buy, the convenience being a major factor for me.

I was just wondering if anybody has tried it as a dessicant in scope and EP boxes, etc?

I know there are cupbord and boat dehumidifier products around, but they seem to be of a disposable nature whereas this stuff looks like it would be reusable after heating.

erick (Eric) · #2 26-02-2010, 02:24 PM

Yes, I saw a recommendation for this material and bought a packet about 2 years ago! Have never got around to opening it

allan gould · #3 26-02-2010, 02:29 PM

It is silica gel and works just the same as the one with the colour indicator.

Barrykgerdes · #4 26-02-2010, 03:07 PM

Don't forget that when it is pink it is full of water.
Dry it out in the oven till it goes nice and blue. Then store it in a dry air tight container.

It is good for keeping taking moisture out of a confined space but it won't be very effective unless you can seal the equipment. Eg. a small cloth bag of it stuffed in a SCT that can be sealed will keep it dry.

Baz

DavidU (Dave) · #5 26-02-2010, 03:10 PM

Yes it sounds great however, It may also have a deodoriser in it and that would be a real disaster for fine lenses !!!! be careful.

Terry B · #6 26-02-2010, 03:26 PM

I foud that it stinks when used for it's intended purpose in a litter tray compared to the normal granules.

allan gould · #7 26-02-2010, 04:23 PM

Quote:

Originally Posted by DavidU

Yes it sounds great however, It may also have a deodoriser in it and that would be a real disaster for fine lenses !!!! be careful.

Bake it several times for 1.5 hr and at 180 degrees C each time should remove all traces of any "deodouriser".

space oddity · #8 26-02-2010, 10:19 PM

Indicating silica gel is best. Although expensive, it is essential to know when saturated. When saturated (typically pink) it releases the water vapour back- putting the humidity back to help fungus grow.

stephenb (Stephen) · #9 26-02-2010, 10:41 PM

Where can you buy those little bags of silica gel from? Anyone?

JethroB76 (Jeff) · #10 26-02-2010, 10:42 PM

Ebay. Camera store?

mldee (Mike) · #11 26-02-2010, 10:44 PM

Plenty on Ebay or online yellow pages.

I'm going to buy a bag of the cat litter crystals and dump some in water to see if the blue crystals turn pink as per comment above.

I'll post the result.

Waxing_Gibbous (Peter) · #12 27-02-2010, 01:57 PM

I'm sniffing some now!
There is a faint floral whiff.
There is also a slightly slimy, liquid residue on the bottom of the container.
I wouldn't be getting it anywhere near a telescope, but a litter-tray in the bottom of your storage area might be OK.
I find a combo of Silica gel, baking soda & generic kitty litter handles most things that don't require a de-humidifier.
If you're spending big $$$ on your gear why scrimp on dessicant?

Tandum (Robin) · #13 27-02-2010, 02:03 PM

I've been using these, they are rechargable and price includes postage.

mldee (Mike) · #14 27-02-2010, 02:26 PM

-"If you're spending big $$$ on your gear why scrimp on dessicant?"-

Thanks for the update Peter, doesn't sound too promising. I was mainly attracted to the convenience of picking it up in Coles during my regular shopping forays, rather than ordering, etc.

mldee (Mike) · #15 27-02-2010, 02:36 PM

Quote:

Originally Posted by Tandum

I've been using these, they are rechargable and price includes postage.

Thanks Robin, The website looked like it's in the US, so initially I thought 'postage cost'.

On reading closer, (as I should have done first), it's on the Gold Coast and as you mentioned, price includes postage. Sounds like a good solution. I'll order some painlessly on line.

OneOfOne (Trevor) · #16 28-02-2010, 10:06 AM

Quote:

Originally Posted by Waxing_Gibbous

...
I wouldn't be getting it anywhere near a telescope, but a litter-tray in the bottom of your storage area might be OK.
...

Jut make sure the cat doesn't find it

gb_astro · #17 28-02-2010, 11:27 AM

Quote:

Originally Posted by Tandum

I've been using these, they are rechargable and price includes postage.

These do look convenient but their recommended 3 hour time in a oven to reactivate sounds ridiculous considering you can zap 40 gms of loose silica gell in a few minutes in a microwave.

Maybe you can do these in a microwave as well??

gb.

mercedes_sl1970 · #18 28-02-2010, 11:46 AM

Quote:

Originally Posted by gb_astro

These do look convenient but their recommended 3 hour time in a oven to reactivate sounds ridiculous considering you can zap 40 gms of loose silica gell in a few minutes in a microwave.

Maybe you can do these in a microwave as well??

gb.

Not trying to sound smart but the aluminium case may be a slight problem in the microwave. Not sure if it is easily dismantled.

Andrew

Tandum (Robin) · #19 28-02-2010, 02:18 PM

Quote:

Originally Posted by gb_astro

These do look convenient but their recommended 3 hour time in a oven to reactivate sounds ridiculous considering you can zap 40 gms of loose silica gell in a few minutes in a microwave.

Maybe you can do these in a microwave as well??

gb.

To be honest, I've never had to reactivate one yet

I just have them in a pelican style case along with my cameras.
It is a tin and doesn't look like it wants to come apart.

gb_astro · #20 28-02-2010, 05:09 PM

(There are lots of metal objects that are microwave-oven compatible.
Just checking that this might be one of them.)

Hi Robin.

In typical Brisbane (where I see you are) humidity, silica gel if exposed
to the atmosphere will absorb as much water as it is going to within the
hour or so. After that it is useless unless reactivated.

That indicator spot on the can should change from blue to pink in a
similar time under similar conditions.
If you have never reactivated yours because the spot has never changed
from blue to pink you would have to think that something is wrong with
the indicator and the crystals inside have saturated long ago.

gb.

For everyone else, after a bit of Googling, found this Qld based lab supplier (ProSciTech) that sells bulk silica gel e.g. 500g:$12, 2kg:$29.
That should last a lifetime.

http://www.proscitech.com/cataloguex...age=c8#c81-005

They also have a good Silica gel FAQs page:

http://www.proscitech.com/cataloguex....asp?silicagel

gb.