The dash sock (silica gel to prevent frost forming on windows)
 

http://ecomodder.com/forum/attachmen...1&d=1295960781

The sock contains about 100g of silica gel. I keep it on the dash for a couple of days and then on a radiator at home over night, this is sufficient to keep ice from forming on the inside of my windshield, saving me from having to idle the car before driving off.

On really cold days i think i'm saving about 5 minutes of idling twice a day. @6 days a week that's and hour, which translates to over a gallon per month. (maybe 1.5)

Very nice solution. I think others have mentioned using silica gel to do the same thing (Pale?). Where does one get a decent quantity of the stuff?

Very interesting ...:thumbup:

However.

I think it may be time for a new sock...:)

>

I don't know, what's in the sock i got from my last job where every gearbox that came in came with a big bag of it. I wish i had saved more, the bags just got thrown away. :(

Maybe, i used to use the microwave to dry it out, sometimes i'd leave it in there a bit too long and the hot silica burned holes in the sock :P

If i find more silica gel i'm going to make another one to use in the rear and try to cut the use of the rear window defroster - that thing is a real power hog.

That is a neat idea! After a month of very low temperatures I had more ice on the inside of my windows than on the outside. Someone advised me to open the windows slightly while driving, but probably didn't take into account that they were frozen shut...
I'm going straight to our collection of old shoeboxes in our basement...
Is radiator temperature (40°-60°C) enough? Wikipedia states

The 120⁰C stated on wikipedia gets all the water out, the radiator just gets much of the water out, which is sufficient for my purposes. (It's an equilibrium reaction)

Edit: saturated the sock weighs ~117g, dried over the radiator it gets to ~107g and dried in the microwave i can get it down to ~104g. (I don't think the extra 3g are worth the hassle)

Silica-Gel-Source and SilicaGelPackets.com
Were some of the first places that popped up when I searched Google. Someone else may have a good source too. Price isn't too bad I guess, it's about $8 for ~100 grams.

Good "modification". :)

Do you know if it also helps to keep the windows from fogging up in warmer weather ?

Without AC - and without robbing the still-cold engine of its heat - my windows tend to fog up in the rain.

I won't use an old sock as a container though ;)

I hate having to run the defroster in winter, knowing it's turning on the A/C. As well, my windows fog up easily once more than one person is in the car. I spend a lot of time trying to keep them clear. I like this idea as well!

...might be an excellent idea down here during the Monsoon Months when temp's are 95-115ºF and humidity is like a "wet sock" slap-in-the-face (pun intended).

Do I see a silica gel group buy coming? ;)

With my LED Fan On indicator, I have noticed that the AC does not run with defrost when it is bitterly cold; like below 20F.

I like the silica defrost sock idea! :thumbup:

Sweet idea! I can imagine using silica gel to prevent the fogging problem in a secondary windshield aeromod.

Check out the kitty litter area at your local grocery or petstore. I've seen a "litter" that's just silica gel crystals. I've used that before for making motorcycle coolant vests (soak in water so the gel picks up moisture but doesn't "drip", which provides evaporative cooling - sort of a like a swamp cooler).

Every pill bottle has silica gel in a little paper packet to keep the pills dry, you can also get silica gel for drying flowers or as was stated, as crystal cat litter.
I was just using some that changes color, blue is dry, pink is wet, it works really well for drying stuff out like cell phones or if you are me, my lap top that I dropped in to standing water... a few hours in a bag of silica gel and it's dry and working just fine!

Personally, I just leave my window cracked open over night, the moist air wants to condense on what is coldest, if the window is open then the coldest thing is the outside as the windshield is still warm, but the windshield is quick to cool so it frosts up quickly.

You can also dry silica gel in the microwave, I don't have one so I used the one next door and found that putting it in for a minute, take it out and stir and cool then put it in for another minute, a flat glass bowl worked best.

what a brilliant idea!!!

as my car doesnt have a/c or a fan!!! i use "fog clear" pretty much isopropyl alcahol or something, it works alright but this is going to have to be product tested :)

Do you know any good brands?

The cat litter crystals I got was just store-brand - just make sure you get the stuff that's *only* crystals (which are a translucent white) and not crystals in clay, because the clay will break down as it goes through wet/dry cycles.

You can also pay for silica gel from gun shops or places online like MidwayUSA. It is used in safes to prevent rust. I pull it from shoe boxes & vitamin/pill bottles also. This way takes a long time to get much gel, unless your wife likes shoes as much as mine does.

Remington makes a "mini-dehumidifier" that plugs into an outlet to get the water out of the silica gel.

There are also some clay products that absorb water out of the air. I believe they are also rechargable. I will have to check on a brand when I get home.

Don

I was thinking about this as an a/c-less option to defrost and then thought silicosis...

Silicosis - Wikipedia, the free encyclopedia
Silicosis is due to deposition of fine respirable dust (less than 10 micrometers in diameter) containing crystalline silicon dioxide in the form of alpha-quartz, cristobalite, or tridymite.

Looks like a simple hepa filter may work. Could be overkill but being overly safe seems like a good precaution...

www.trockenmittel-shop.de sells Silica gel

Example :
240 bags with 60 gram (+/- 4 bags to a pound) silica gel wrapped in Tyvek are 95 euro.


It boils down to 2.5 bags per euro.
Postage would be a deal killer if it had to be sent from Belgium though :(

I have used a gallon jug of water to keep ice off the windshield, as it freezes, it releases heat (latent heat of fusion). I suppose a few liter bottles would work too.

Thanks for sharing your sock idea. Now I can finally get serious about removing my A/C belt without worrying about the windows fogging up.

One question though : Since I am in Texas, we don't get that white cold stuff that falls from the sky here. My main problem is instant fogging of the windshield on a hot muggy day.
What kind of preparation is needed in my situation, and how long will this thing last if I leave it in my car ?
Thanks again

In that case of hot humid weather, bring a squirt bottle full of soapy water and apply to the fogged up window when needed.

I know where to get ample supplies of silica gel for next to nothing.

Disposable diapers

Just get the unused variety. Sometime recycling isn't a good idea :P

Are they reversable like silica gel ?

They will absorb water, but I'm not too sure they will absorb water vapor.


LMAO !!! :)

Am I the only one that puts wet diapers on the radiator to re-use them later?

I'm about to get my electric car back on the road and due to the lack of A/C and almost no cabin heat it can be hard to keep the windshield fog free so one thought that I had was to install a dehumidifier in the car, behind the seat and plug it in to the spare plug from the charger plug so that it would come on whenever the car was plugged in.
A google search came up with two decent options dehumidifiers for RVs/cars EDV-1100 Eva-Dry Electric Petite Dehumidifier that are also targeted at keeping closets and under sink cabinets dry, the other option is kind of like the silica gel filled sock, only in a fancy plastic case. Amazon.com: Eva-dry EDV-E-500 Renewable Wireless Mini Dehumidifer: Health & Personal Care

Re. safety -
I found this on the Wikipedia page on "silica gel":

Silica gel is non-toxic, non-flammable, and non-reactive and stable with ordinary usage. It will react with hydrogen fluoride, fluorine, oxygen difluoride, chlorine trifluoride, strong acids, strong bases, and oxidizers.[6] Silica gel is irritating to the respiratory tract and may cause irritation of the digestive tract, and dust from the beads may cause irritation to the skin and eyes, so precautions should be taken.[8] Some of the beads may be doped with a moisture indicator, such as cobalt(II) chloride, which is toxic and may be carcinogenic. Cobalt (II) chloride is deep blue when dry (anhydrous) and pink when moist (hydrated).

Crystalline silica dust can cause silicosis but synthetic amorphous silica gel is non-friable, and so does not cause silicosis.

Re. where to get it:

I found multiple versions when I searched for "Silica gel" on Amazon. Below are a few offerings that might be worthwhile for individuals - not necessarily for a group buy:

Amazon.com: 4 pack of 112 Gram Silica Gel Desiccant Packets 6" x 4.5" By Dry-Packs Brand! Prevent Mold, Mildew, Odors, and Corrosion!: Office Products

Amazon.com: Peli Desiccant Silica Gel, 4-Pack: Home Improvement

Amazon.com: Dry-Packs Portable Dehumidifier Box - 450 Gram Silica Gel - Protects 33 CU FT! Can Be Reactivated, Indicator Included!: Home Improvement

Lee Valley sells it as well

Silica Gel Dehumidifiers - Lee Valley Tools

I have that disabled in my mp5.
but I also have to manually (under the dash) change my venting. not sure how the subi is setup, but on the mazda, when you turn the dial to get it over to the 2 defrost settings, it toggles a little switch on the vent table under the dash. Ive thought of a couple different ways to bypass it and still have the use of my ventswitch on the dash, instead of climbing under it if I want to switch where the air is blowing from, but as it stands now it works pretty darn good.
although, I do have to wait a little extra time for the car to heat up to provide dryer, warm air, its not so terrible as to offset that Im not using the AC unit.

Well i went BIG last week and bought 10kg of kitty litter. (I can't believe people spend $20 per month just so their cat can poop)

It was pure silica gel, irregular shape crystals, but it seems just as good as those balls you get in bags. I filled more socks (clean ones without holes this time) and now i can theoretically get 100g of water out of my car per day! And i have to figure out what to do with the other 9kg of this stuff.

Easy: get a cat!

I've found a pet shop with silica gel cat litter, but the balls of silica are bigger than the silica gel in the packets found in packages. If I were to crush the cat litter into smaller pieces would the silica gel be more effective by having more surface area?

Yes, if the balls are solid silica gel.

About 2-3 months ago I traded my neighbor some car work for a sock full of their cat's silica gel (not used, they claimed). You should have seen the expression on their faces!

Anyhow I have 300g of the stuff, which gives up over 20g of water after 2-3 minutes in the microwave (I've measured only 1-2 times). After heating I let it cool down for 30 minutes. Now, should I take it to the car when I get in, or a bit earlier to get a head start? How long does it take the silica gel to "charge"?

I also noticed that a fine dust comes out of the sock when handling it. Could the crystals be deteriorating in the microwave?

Any other advice on using it?

You'd best leave it in there and let it soak up the moisture.

That'd be fine silica dust.
Don't inhale it.

Put the microwave on a lower output - lowest possible - and heat it more gently.
Or preferably put it on the heating.
You're likely blowing up the crystals.
Steam is 1200 times more voluminous than liquid water.
If the steam has no time to escape, it'll blow apart whatever tries to contain the expansion.

Put it in a bag with smaller holes / pores than a sock.

I think that a hygrometer in the cabin is also useful. It is good to see if the sock works and how well.

The sock I have weighs about 575 grams when I bring it home. After 5-10 minutes of warming in the microwave, when the silica gel has more or less "steamed off", it weighs 25-30g less.

How that translates to keeping the windshield dry is another matter - is this 30g of water which didn't condense on the windows, or is it 30g of water vapour which would have been expelled out of the car anyway?