Window Fogging

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rwidman

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We usually operate our boat from the flybridge, but if it's cold or raining, we operate from the lower helm. The problem is, the windows fog up, especially if we've been sleeping on the boat with it closed up.

I've tried a portable fan aimed at the windows and it helps a little but it's just blowing humid air at the windows.

Are there any products that can be applied to the glass to minimize fogging? Do they work? Any other suggestions besides electrical defrosters?

-------------------

Second question - The outside of the windows. The wipers work after a fashion but they don't cover as much area as they should and they leave streaks. I tried Rain-X on them a while back and it seemed to cloud the windows so I did my best to remove it. Is it a good product and I just didn't get the windows clean first or didn't use enough, or is it a waste of time and effort?
 
If you need to see short term.

Use some dish washing liquid on a paper towel. Smear it around the fog will go away. Works for quite a while.

I keep a squeegee on the dash. That works great. You just have to keep squeegeeing

If you use a fan you need a really strong one. You really gotta blow some air at them.

Sd
 
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I also use a squeege, I have an automotive cigarret lighter plug small 12V fan /heater combo which helps a bit.
Rainx make a anti fogging wipe but it hasn't been a big help. A couple of months ago I bught a small Carafamo fan 12v but pushes a lot of air I'm hoping it will do the trick.
sorry no real answer
Steve W
 
We usually operate our boat from the flybridge, but if it's cold or raining, we operate from the lower helm. The problem is, the windows fog up, especially if we've been sleeping on the boat with it closed up.

I've tried a portable fan aimed at the windows and it helps a little but it's just blowing humid air at the windows.

Are there any products that can be applied to the glass to minimize fogging? Do they work? Any other suggestions besides electrical defrosters?

-------------------

Second question - The outside of the windows. The wipers work after a fashion but they don't cover as much area as they should and they leave streaks. I tried Rain-X on them a while back and it seemed to cloud the windows so I did my best to remove it. Is it a good product and I just didn't get the windows clean first or didn't use enough, or is it a waste of time and effort?
Ron, we have the same problem. I use Rain-X rather than wipers and it works well on the outside. I'm not sure why your's turned milky, although I believe Rain-x is not recommended for other than glass, so that might be the problem. For the inside during winter cruising, we just keep the Dickinson on all night with the pilot house hatch vents cracked and that gives the moisture someplace to go. The water vapor will condense no matter what you do I think, unless you can blow hot air on them to keep it in vapor form, I think the only solution is allowing for air removal to take the moisture with it.

If your glass isn't glass, they make a Rain-X like product for aircraft you can get from Sporty's that should work. I used a cleaner on the glass of my airplane and moisture beaded up well after applying it. Marin can probably make a current recommendation.
 
We usually operate our boat from the flybridge, but if it's cold or raining, we operate from the lower helm. The problem is, the windows fog up, especially if we've been sleeping on the boat with it closed up.

I've tried a portable fan aimed at the windows and it helps a little but it's just blowing humid air at the windows.

Are there any products that can be applied to the glass to minimize fogging? Do they work? Any other suggestions besides electrical defrosters?

-------------------

Second question - The outside of the windows. The wipers work after a fashion but they don't cover as much area as they should and they leave streaks. I tried Rain-X on them a while back and it seemed to cloud the windows so I did my best to remove it. Is it a good product and I just didn't get the windows clean first or didn't use enough, or is it a waste of time and effort?

Ron: We have 2 Hella fans, one in each corner of the helm windows. When in the PNW we'd point the fans toward the windows and they worked as great defrosters. When it is hot, we turn them around so to get the air moving in the pilot house (sorry for the poor pic quality).

Other then new wiper blades, I have no idea on the streaks. We have never tried Rain-X..
 

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Ron: We have 2 Hella fans, one in each corner of the helm windows. When in the PNW we'd point the fans toward the windows and they worked as great defrosters. When it is hot, we turn them around so to get the air moving in the pilot house (sorry for the poor pic quality).

Ron, we have the same set up as Larry. It works. On cold mornings we run the heat and the fans for a good while before starting out. That dries out the air, and the fans have time to get the windshield clear.
 
We usually operate our boat from the flybridge, but if it's cold or raining, we operate from the lower helm. The problem is, the windows fog up, especially if we've been sleeping on the boat with it closed up.

I've tried a portable fan aimed at the windows and it helps a little but it's just blowing humid air at the windows.

Are there any products that can be applied to the glass to minimize fogging? Do they work? Any other suggestions besides electrical defrosters?

-------------------

Second question - The outside of the windows. The wipers work after a fashion but they don't cover as much area as they should and they leave streaks. I tried Rain-X on them a while back and it seemed to cloud the windows so I did my best to remove it. Is it a good product and I just didn't get the windows clean first or didn't use enough, or is it a waste of time and effort?
Ron, the few times that it was cold enough when cruising to use the lower helm- I had to crack the side doors open a bit to keep the windows from fogging. Presumably the lowered the saloon temp enough to be closer to the outside temperature.
 
We use a towel and a small Caframo 747 fan like this
d9671fe269c11ad5e17deae1d037.jpg


to move the air. Works well to keep the crew cool, too. This thing is very low power consumption, moves lots of air and is very quiet, even on the high speed. It comes with a fixed and suction mount.

Here's a shot of the Admiral and me modelling the new shirt given me by Mark Pierce for our Fleet Week/America's Cup Day on the Bay! If you look REAL close, you can see the fan stuck to the windshield on the left edge of the photo.
 

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We use a towel and a small Caframo 747 fan like this
d9671fe269c11ad5e17deae1d037.jpg


to move the air. Works well to keep the crew cool, too. This thing is very low power consumption, moves lots of air and is very quiet, even on the high speed. It comes with a fixed and suction mount.

Here's a shot of the Admiral and me modelling the new shirt given me by Mark Pierce for our Fleet Week/America's Cup Day on the Bay! If you look REAL close, you can see the fan stuck to the windshield on the left edge of the photo.

Just wondering. . . . . . In the San Francisco area how do you guys tell if the fog is on the inside our outside of the window?
 
Rain-x has performed well for me. I found if applied in the heat it would come out cloudy. A sprinkle of water and some buffing seems to take care of that problem. The idea of the Rain-x is to fill the pores of the glass. Another way to make the glass smoother is to polish it. I used a glass polish from Car Care, Detail Supplies, Garage Organization, Car Accessories - Griot's Garage 800-345-5789 and a small random orbit polisher. This serves to smooth out the glass and remove any surface contaminants that do not let the water bead up and roll off.
 
Ron--- We use a fan mounted by a previous owner in the upper port corner of the main cabin that blows air onto the front windows. This works well for us in clearing the three front windows. The fan has a lever that can change it from fixed direction to swivel, so it also works on hotter days to move air in the main cabin.

We have tried the dish-soap-on-the-inside trick on the other main cabin windows and while it works after a fashion you get a soap buildup on the glass and subsequent hazing so it all has to be cleaned off at some point and then you start over.

I am not a fan of Rain-X at all, and I know how to apply it properly. On a car where the speed blows water off the windshield, it works okay for awhile. The use of wipers degrades the Rain-X coating pretty rapidly, however. And it does tend to cause some fogging/glare at night with oncoming lights.

But on a boat, particularly a slow boat like ours, we've found Rain-X to be virtually worthless. It doesn't help at all in fine rain or mist because the droplets don't weigh enough to slide down the windshield on their own. So you have to use the wipers anyway which destroys the Rain-X coating in short order.

Rain-X does work as advertised to move heavy spray off the windshield. But we find that to be able to see well enough to spot debris, crab pot floats, etc. in the water in front of us, particularly if the water is rough-ish, we need to use the wipers, too. So again, the Rain-X coating is gone pretty quickly, particularly in this case when the water being wiped off is salt water.

Regular rain isn't an issue for us as the flying bridge overhang protects the wiindows fairly well unless it's real windy.

Fortunately our boat has excellent wipers. They are the stock units that were installed when the boat was built in 1973. I believe they're API (sp?) although I have no clue as to the model. The only change we've made has been to replace the stock straight wiper arm on the center windshield with a pantograph arm to get a lower arc of clear glass in front of the helm. But we have no complaints about our wipers at all and they do a far better job of giving us a clear picture forward than Rain-X does.

So we no longer bother with Rain-X at all.

Rain-X makes an interior anti-fogging product, too. We've tried it, and while it works to a degree we did not find it effective enough to warrant the effort of putting it on. It's not as messy as using soap. But every situation is different and you might find it works well for you.

So other than the fan on the front windows we simply wipe the rest of the windows down with a towel.
 
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Ron, we have the same problem. I use Rain-X rather than wipers and it works well on the outside. I'm not sure why your's turned milky, although I believe Rain-x is not recommended for other than glass, so that might be the problem. For the inside during winter cruising, we just keep the Dickinson on all night with the pilot house hatch vents cracked and that gives the moisture someplace to go. The water vapor will condense no matter what you do I think, unless you can blow hot air on them to keep it in vapor form, I think the only solution is allowing for air removal to take the moisture with it.

If your glass isn't glass, they make a Rain-X like product for aircraft you can get from Sporty's that should work. I used a cleaner on the glass of my airplane and moisture beaded up well after applying it. Marin can probably make a current recommendation.

My glass is glass. I might try it again after making sure the glass is squeaky clean.

We have no heater other than the reverse cycle AC which can't be used away from the dock. Actually, I have an electric cabin heater from West Marine that I bought when the reverse cycle quit a couple years ago. I actually got it out and used it last year powered by the inverter, but we all know that's losing proposition. All I could do is try to take the chill off while underway.
 
tried the anti-fog goop on the inside windows- works ok for awhile.

The best solution was to plumb a red-dot engine heat radiator with fans to push the warmed air around. Mounted it under the stairway leading forward from the pilothouse which is located just under the center windshield.

This directs enough warm air right to the glass which then defeats the condensation - sometimes will additionally crack a pilothouse door to bleed out the moisture.
 
never use rainex on the inside unless it is their no-fog formula...regular rainex just makes the fogging worse.

if you have a genset...a small cube heater will make short of any fogging.
 
Just wondering. . . . . . In the San Francisco area how do you guys tell if the fog is on the inside our outside of the window?

What fog?

img_107479_0_bed5ade47399edc8f10f0575c0e99eff.jpg
 
Greetings,
The trick is to lower the dew point. Dew point - Wikipedia, the free encyclopedia
Either by raising the temperature with heaters etc. or "diluting" the moisture laden air by mixing with dryer air (fans). If the whole boat is humid, moving internal moist air about with fans will do little to clear fogging from windows. Crack a port or warm the air. Oh, and shut down your bong....
 
RTF is right. We will sometimes open the center window just a crack which in conjunction with the fan clears fogging on the windshield panes very quickly.
 
If I am on shore power before leaving, I would have my portable dehumidifier running overnight. This generally diminishes condensation. When underway, if it is minor, I use microfibre towels and open the top half of my pilothouse door. If it is raining out, I will run my generator and reverse cycle air, which works great as there is a large outlet in the pilothouse. After about 10 minutes there is no condensation. Not much luck at all with Rain X.
 
My boats past and current are in the 6-7 knt class. Upright pilothouse windows, on one and near vertical on the current. I use Rain-X. When the average wind is 15 knts SE one can be assured the rain is blown away to the extent that I rarely use the wipers. As to the inside fogging issue, I to use Joy soap. Yes, occasionally the need to use windex in a full clean up is required, but that is normal housekeeping.
For sure, oil heat or Red Dot is the preferred source over propane. I demand both on any boat I own.
Nice to read of the various approaches. Thanks.

Al Johnson- Ketchikan
27 Marben-
 
But on a boat, particularly a slow boat like ours, we've found Rain-X to be virtually worthless. It doesn't help at all in fine rain or mist because the droplets don't weigh enough to slide down the windshield on their own. So you have to use the wipers anyway which destroys the Rain-X coating in short order.

Could be you're glass is angled the wrong way. :hide:

That said, Rain X works great on my vertical pilothouse ports.

For interior fogging, I have the old school tubular hella fans which work quite well.
 
Could be you're glass is angled the wrong way. :hide:

I asked the mist droplets about that one day and they said, nah, they don't care which way the glass is angled. They said they weren't gonna slide down no matter what.

I said, "But we've got Rain-X on the glass."

They laughed and one of them said, "Rain-X? We're not afraid of your stinkin' Rain-X. We piss on your Rain-X. You want us to move you'll have to sic a set of wipers on us."

So we did.
 
Cut a potato in half , rub the area you want clear with it , then wipe with a paper towel.
 
Cut a potato in half , rub the area you want clear with it , then wipe with a paper towel.

I suppose, but we normally don't keep potatos on the boat. I need something that will keep but be ready for use when necessary.

Some parts of the glass are very difficult to reach.
 
McDonald's fries I hear keep pretty well.
 
GonzoF1 said:
McDonald's fries I hear keep pretty well.

Man, I found a couple of those between the front seats of my pickup...they were as good as when they fell in there last April!
 
Man, I found a couple of those between the front seats of my pickup...they were as good as when they fell in there last April!
Ha! Did you ever see the movie Supersize Me? There were some DVD extras that I watched. One was with several food products including McD's french fries under glass for months. Much of the food began to decay and form mold after varying periods of time. The fries underwent with NO CHANGE! It was like they were made of plastic or something!
 

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