Fran said:[email hidden] said...
Quoted message said:"Fran" <[email hidden]> wrote
Quoted message said:Here's what it says on Field and Trek's website, but what, in plain English, does it actually
mean? *How* and *why* does it work? Assuming, of course, that it does...
Quoted message said:Probably just a bag of silica gel isn't it?
Probably.
Quoted message said:I'd have thought newspaper would have worked better for jobs like drying out wet boots.
Having now read some other responses, and had time to think about it a bit, does the gel have to
be in physical contact with the wet thing? What I mean is, if the gel is itself in a bag of some
sort, then surely the bag has to absorb the wetness from whatever you want to get dry so that the
gel can then dry the bag. It seems an awfully long-winded way of doing things, although I suppose
if you're out in the wilds and get soaking wet... but no, that wouldn't work would it, because
surely the drying process would take too long? You know what? I'm getting further and further
from being convinced of the efficacy of this product. Even if it did come into its own in the
wilds, presumably it would take on all the weight of the original wetitude until it could be
dried out again...
Silica gel works by dehumidifying the atmosphere. Once you get an humidity less than a certain
amount (which is defined by the temperature) then water will start evaporating from any reservoirs
into the air - it's then taken up by the gel.
So to actually use this thing.
1. Dry out the gel. Hot pipe is probably the best way.
2. Remove as much moisture as possible from the wet item.
3. Seal inside a water tight chamber such as a ziplock bag. You don't need to reduce the air inside
but don't use a bage bigger than is needed.
4. Increase temperature modestly. Place near a room heater etc.
The gel effectively tugs water from the air, and the dry air tugs it from the thing to be dried.
It's worth noting that some things may well tug back - natural fabrics such as cotton etc love
to hold on to water due to hydrogen bonding and will take longer to dry, rayon and nylons will
dry quickly.
If you don't overload the system then it will work well, I used to use silica dessiccators at Uni to
get exceedingly dry samples. However the capcity of silica gel for water is not as great as say
cottons capacity for water, so I'm not sure just how much is going to be needed.
--
5.84% of all statistics are made up on the spot. The other 42% are made up later on. In Warwick -
looking at flat fields and that includes the castle.
