Silica Gel + Tupperware as dry box?

[ortega]

but hor, if you study it

it does nothing except,

1. contain selica gel
2. once selica get turns pink, you plug it in and it will heat up the selica gel and it will turn blue again, ready for use.

IMHO not worth it.

 

[Canew]

Yes, that is EXACTLY what it does. :bsmilie:

 

[cjtune]

Yes, that is EXACTLY what it does. :bsmilie:

I think that's all how all dry cabinets work... except it is continuous and probably self-regulating...

 

[wetmarket]

This topic sounds interesting... I wonder if adding Thirsty Hippo into a big-size tupperware will work??:think:

 

[Snoweagle]

Silica gels CAN regulate PH.
Put enough of the beads inside a container, and you'll see them reach a certain equilibrium RH (relative humidity) with the air, usually on the low side like 30-40% RH.
They can be used -supposedly indefinitely- by reheating them in ovens, microwaves. That is also the major hassle. Have to reheat them on low power to avoid damaging them and this can take quite a long time (nearly an hour if for a lot of silica beads!).

I have just put together a 40+ L plastic tub (S$10) with a hygrometer (S$14) and currently a large pack of Thirsty Hippo (S$2.50), because I don't feel like paying nearly S$200 for a similar-sized regulated dry cabinet to keep my camera bags inside. Where I live, it can get humid enough that mold can start growing even on the bags. I have been using silica gel for my clothes wardrobe and in a container where a mildly-fungus-infested lens is in 'solitary confinement'.

I keep the camera body, lenses, and flash inside a proper 40L dry cabinet though.

Silica gel's RH depends on how much u put so it's not stable. If u want to reach your desired RH usually it's more troublesome.

 

[cjtune]

Silica gel's RH depends on how much u put so it's not stable. If u want to reach your desired RH usually it's more troublesome.

So put more than what you need...
There's a rule of thumb when sizing the amount of silica gel to use: silica gel can hold as much water as its own dry weight.

Agreed, you cannot reach a desired RH just by having a packful of silica gel without any controller mechanism. But it will usually peter out and stabilise at the low 30% or so RH. Reason being a thermodynamic balance: drier air resists the adsorptive force of the silica gel more (dry air also has its own affinity towards moisture), and no container ca be perfectly sealed -ie. fresh moisture will still continually leak in from the outside.

So will very dry air cause grease and oils to dry out faster? I asked this at a lubrication seminar recently. Yes, but it is a very much smaller factor than having your greased/oiled item in a hotter environment, ie. temperature is still the major driving factor.

 

[Snoweagle]

So put more than what you need...
There's a rule of thumb when sizing the amount of silica gel to use: silica gel can hold as much water as its own dry weight.

Agreed, you cannot reach a desired RH just by having a packful of silica gel without any controller mechanism. But it will usually peter out and stabilise at the low 30% or so RH. Reason being a thermodynamic balance: drier air resists the adsorptive force of the silica gel more (dry air also has its own affinity towards moisture), and no container ca be perfectly sealed -ie. fresh moisture will still continually leak in from the outside.

So will very dry air cause grease and oils to dry out faster? I asked this at a lubrication seminar recently. Yes, but it is a very much smaller factor than having your greased/oiled item in a hotter environment, ie. temperature is still the major driving factor.

That's y dry boxes with hygrometers are used in this case.

 

[ipin]

From the Material Safety Datasheet of INDICATING SILICA GEL (Cobalt Impregnated) states :

"Carcinogenicity:
Cobalt and its compounds have been shown to cause cancer in laboratory animals."

I don't find any reason to subject myself and others in my household to this kinds of risks. IMO, since one has already spent that much on a camera system, what is another S$100-S$200 on a dry cabinet firstly to protect the gear, 2nd to protect his/her loved ones? :dunno: Just plug it into an electrical socket, set it to the desired %RH (Mine's between 45-50 %RH) and let the digi cabinet do the work. :lovegrin:

Besides, the trouble of having to re-generate the silica gels on a regular basis is time consuming and tiring. :sweat:

 

[doyqw]

Thanks to all who've contributed! I just bought a Digi-Cabi DB-036 today to replace my tupperware.

 

[Snoweagle]

Thanks to all who've contributed! I just bought a Digi-Cabi DB-036 today to replace my tupperware.

Gd choice! :thumbsup:

 

[ipin]

Thanks to all who've contributed! I just bought a Digi-Cabi DB-036 today to replace my tupperware.

You wun regret it :thumbsup:
(Until you start building up on your gear and soon it'll be time to upgrade! :angel: )

 

[Artosoft]

I think that's all how all dry cabinets work... except it is continuous and probably self-regulating...

Different, dry cab and dry box are using different way to achieve low humidity inside the box. Dry cabinet doesn't use silica gel to absorb humidity. Modern dry cabinet dehumidifier use peltier/thermocouple principle to move 'water in the air' from inside dry cabinet to outside. It is safe because no cobalt chloride used in dry cabinet.

Regards,
Arto.

 

[cjtune]

Different, dry cab and dry box are using different way to achieve low humidity inside the box. Dry cabinet doesn't use silica gel to absorb humidity. Modern dry cabinet dehumidifier use peltier/thermocouple principle to move 'water in the air' from inside dry cabinet to outside. It is safe because no cobalt chloride used in dry cabinet.

Regards,
Arto.

Funny, I can't find Peltier elements mentioned anywhere in these dry cabinet manufacturers' FAQs:
http://www.empf.org/empfasis/2006/jan06/mcdry0106.html
http://www.totechamerica.com/articles/drycabinets/print.php

Can you cite some examples of these so-called modern dry cabinets? Perhaps they are meant for industrial use. Removing moisture from air by cooling will hit a limit of the air's capacity at that temperature -it cannot be coerced to go lower than that unless you have an adsorptive mechanism at play, such as those from silica gel or zeolite.

 

[cjtune]

From the Material Safety Datasheet of INDICATING SILICA GEL (Cobalt Impregnated) states :

"Carcinogenicity:
Cobalt and its compounds have been shown to cause cancer in laboratory animals."

I don't find any reason to subject myself and others in my household to this kinds of risks. IMO, since one has already spent that much on a camera system, what is another S$100-S$200 on a dry cabinet firstly to protect the gear, 2nd to protect his/her loved ones? :dunno: Just plug it into an electrical socket, set it to the desired %RH (Mine's between 45-50 %RH) and let the digi cabinet do the work. :lovegrin:

Besides, the trouble of having to re-generate the silica gels on a regular basis is time consuming and tiring. :sweat:

How did they induce the cobalt (II) chloride into the lab animals?
Google around and you'll find the melting point of CoCl2 is about 700'C and its boiling point is 1000+'C. Danger might come if somehow the silica gel impregnated with it gets crushed and reduced to fine dust that hangs around in the air, or if the CoCl2 get diluted into water and gets sprayed around as aerosol.

Anyhow, for a fully picture, you can read a (very) lengthy report here:
http://www.intox.org/databank/documents/chemical/cobaltcl/ukpid50.htm

Note also the report cites a possibility of it being a human carcinogen. There are other chronic adverse effects on humans from ingesting/inhaling cobalt compounds but they seem to manifest themselves mainly so far in workers from the minerals industry. Probably from exposure to floating cobalt dust.

 

[Artosoft]

Funny, I can't find Peltier elements mentioned anywhere in these dry cabinet manufacturers' FAQs:
http://www.empf.org/empfasis/2006/jan06/mcdry0106.html
http://www.totechamerica.com/articles/drycabinets/print.php

Can you cite some examples of these so-called modern dry cabinets? Perhaps they are meant for industrial use. Removing moisture from air by cooling will hit a limit of the air's capacity at that temperature -it cannot be coerced to go lower than that unless you have an adsorptive mechanism at play, such as those from silica gel or zeolite.

IIRC, the diagram on how it work is drawn on the digi-cabi box. Believe me, it is peltier technology/Thermo couple/Thermo electric principle.

Regards,
Arto.

 

[Artosoft]

How did they induce the cobalt (II) chloride into the lab animals?
Google around and you'll find the melting point of CoCl2 is about 700'C and its boiling point is 1000+'C. Danger might come if somehow the silica gel impregnated with it gets crushed and reduced to fine dust that hangs around in the air, or if the CoCl2 get diluted into water and gets sprayed around as aerosol.

Anyhow, for a fully picture, you can read a (very) lengthy report here:
http://www.intox.org/databank/documents/chemical/cobaltcl/ukpid50.htm

Note also the report cites a possibility of it being a human carcinogen. There are other chronic adverse effects on humans from ingesting/inhaling cobalt compounds but they seem to manifest themselves mainly so far in workers from the minerals industry. Probably from exposure to floating cobalt dust.

As stated on many sites, Cobalt Chloride for blue color humidity indicator found on blue silica gel is carcinogen. Silica gel itself is not carcinogen.

If you doubt it, nobody will against you. You are free to buy it and use it as much as you like.

Just let me remind you, it is not for fun when you are near carcinogen agent, while you have an option for dry cab.

Regards,
Arto.

 

[ipin]

I'll say, go for the dry cabinet! Hassle free and Cobalt just isn't worth the risk IMO. :sweat:

 

[cjtune]

IIRC, the diagram on how it work is drawn on the digi-cabi box. Believe me, it is peltier technology/Thermo couple/Thermo electric principle.

Regards,
Arto.

Perhaps it is so, for the heating element? But I seriously doubt it is not based on adsorption by either silica gel and zeolite. In other words, the TEC is not the one that is actively removing the moisture.

 

[cjtune]

As stated on many sites, Cobalt Chloride for blue color humidity indicator found on blue silica gel is carcinogen. Silica gel itself is not carcinogen.

If you doubt it, nobody will against you. You are free to buy it and use it as much as you like.

Just let me remind you, it is not for fun when you are near carcinogen agent, while you have an option for dry cab.

Regards,
Arto.

Agreed, silica gel is inert and harmless. The CoCl2 doping is an animal carcinogen. May be possibly carcinogenic for humans. Plus, the mechanism of ingestion and inhalation is rather limited to extreme cases, in my opinion. Of course, it is your right to fear it as much as you want but note that it has been used for many many decades already in its current capacity.

I am exposed to proven human carcinogens almost every day. It's called Char Kway Teow and french fries, and 2nd-hand smoke.

 

[Artosoft]

Perhaps it is so, for the heating element? But I seriously doubt it is not based on adsorption by either silica gel and zeolite. In other words, the TEC is not the one that is actively removing the moisture.

I hope you know what is peltier element is. That's make easier to me to explain.

Peltier element have a cold and hot side when direct current (DC) run across it. The cold side is inside dry cab. It will condense humidity inside dry cab into water. The water will going down and there is a sponge that act as a water transfer, but will block the air transfer (so the dry cab is isolated to outside air). This water will go outside dry cab and heated by hot side of peltier element, evaporate to environment. Clever idea I always said.

That's how the humidity inside dry cab is move to outside, not by silica gel or zeolite.

Regards,
Arto.