Just like the topic says...and does it help decrease brakedown of the car or increased brakedown elsewear? What is everybody's thoughts on what humidity regardless of sun exposure does to their XK's? Im a goofball..i just dont know... rust? leather damage? the XK shouldnt rust with aluminum right?

Loth

 

Yes, I have one. All the car websites I checked said somewhere around 40-50% was ideal..any less was not good and any more was too humid. I keep mine at 40% and it really keeps the cars nice. Had one in my garage since the late 1980's and it truly helps keep everything fresh.

 

Alu does oxydate indeed.
do you use a negative ion generator? lol its cheap. I used one before in the car and it make me relax.

 

Aluminum is highly resistant to corrosion. The oxide layer that forms on exposed surfaces is protective of the surface and does not progress as a source of corrosion itself. Damage to aluminum is most readily caused by alkaline chemicals, because they damage the oxide layer. If damaged, aluminum immediately forms a new oxide layer, re-establishing the protection. This assumes the source of damage has been removed.

Road grime that sticks to the undersurface of exposed panels, or gets wedged into joints is a primary source of this type of ongoing exposure of dangerous environmental alkalis that will damage the metal (this is called poultice corrosion). Also, Aluminum acts as an anode to most metals when placed in an ionic solution, so trapping seawater or de-icing salts in a joint between aluminum and another metal will cause corrosion there.

Corrosion usually occurs only in isolated (sometimes microscopic) areas that are subjected to these insults, and does not spread the way a small spot of rust will spread over a steel-bodied car. At some point the ionic solution dries, or the chemical is washed away, and a new oxide layer forms, re-establishing the previous level of protection.

It is important to consider the dew point at which water will condense on your aluminum surface. Water condensate in the presence of ions and impurities such as air pollution or road grime will damage the aluminum surface.

Temperature will greatly affect the rate of corrosion. In industry, operation of aluminum machines at slightly above ambient temperature will speed the surface drying process and will shorten exposure times to wet surfaces. But other than that the rate of corrosion will vary depending on the chemical that is doing the corroding. In one graph I found the corrosion rate of sulfuric acid increased from 25 mm/yr at room temperature to 115 mm/yr at 120 deg F (the temperature of a hot garage). I hope your car is not often exposed to hot sulfuric acid, but I could see microscopic exposure from road grime as a potential source of such corrosives.

Filiform corrosion is another type of aluminum breakdown that occurs in warm coastal regions and polluted industrial areas, and is directly affected by relative humidity (between 55% and 95% in highly polluted environments or between 85% and 95% in natural atmosphere). This is a chemical reaction and presents as a bubbling, thin, worm-like progression between the aluminum and an applied coating, such as primers and paints. Airlines see this problem in planes that routinely fly over ocean waters.

In our cars, filiform corrosion may sometimes be seen starting from a scratch made in the paint coating. Auto manufacturers have done considerable testing to choose alloys that resist filiform corrosion. The quality of the pre-treatment surface is also an influential factor in addition to environment.

Source: Corrosion of Aluminum and Aluminum Alloys, Joseph R. Davis.

 

^ I was going to go into more detail, but that's the gist of what I was going to say

 

I have an unattached garage in the northeast with a couple of bikes. I put these under the bikes during the winter to prevent rust.

GoldenRod Dehumidifier Rod Detachable Plug 110v Gold

 

Did I overdo it? Sorry! I guess that was a long way of saying your car's aluminum will outlive you, so don't sweat it. I thought of two other issues:

Mold and mildew: The Texas A&M Ag Extension suggests 30-60% to prevent mold and mildew indoors.

Wood paneling swelling and drying: My friend keeps a climate control system inside his piano which maintains a year-round humidity level of 40% surrounding the sound board. He says it's not the level of humidity so much as the change in humidity that damages the board over time and changes the tuning from season to season as it swells and contracts. One of my pet peeves is cracking in the wood paneling on cars, so maybe just consistency is sufficient to prevent this.

Ok, I'm letting it go now...

 

Actually, I thought your post was great!
I never worry about the body/chassis from the humidity standpoint. Its the interior and leather ect.. I have the dehumidifier in the garage to protect that stuff.

 

Great write up. Just over a question. I had my car undercoated with a wax protection from "perma shine". I live in Canada. I don't drive the XKR175 in the winter but I thought this would help it the long run. Do you see any problems with this treatment?

I had 2 dehumidifiers in my 1800sq ft. garage. During the winter mildew would form on the garage door windows. I removed them because I would also need to keep the heat up for them to be effective.

 

dust collector should be considered too.

 

So you got mildew even with the dehumidifier?

My XK has a rubberized coating on the undersurface of the monocoque already, I guess to protect from rock and scrape damage. There are also some perforated heat shields or something that are bare aluminum, and even these still look brand new. So I think the wax was unnecessary, but I can't see how it would hurt anything, either.

 

My experience: I live in the north east and i tend to get a ton of snow or rain in the car. I originally ordered one for my car which had very high humidity and covered the windows with window plastic. That helped a lot but humidity still not in the 45% range.I put a dehumidifier (I can't say the brand) inside to prevent rust on the screws on the cars, humidity went down to 40% in a matter of a day! These work great if you understand how they work (https://cardehumidifiers.com/car-moi...sture-absorber) and their limitations.

 

Oops, a nine-year-old thread suddenly brought back to life.
I live in a desert, humidity is 30% on a wet day.

 

I do exactly the same thing to my bikes and the Jag. Also in a detached garage.

 

Your nine year old quote of yourself contains a nine year old link. Of course it doesn't work.

 

I've been running a dehumdifier in the garage for a couple of months now. Makes it a much more comfortable space and go knowning the cars are exposed to additional humidity. Why I didn't do this years ago is beyond me!

Next step is to use the pump so I don't have to dump it out daily.

 

It isn't hard to cut a hole into the rear wall of the garage and install a window A/C unit. I keep the temp at 78 and humidity takes care of itself. Almost like parking the car in your living room!