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Normanj
12th June 2011, 12:20 PM
I'm not sure my post belong here but it seems the closest to my problem.

My garden shed (I do my woodwork elsewhere) is used to store a range of tools, together with paint, solvents and pool chemicals. I've noticed that some of the tools are corroding much quicker that I would expect (they are usually wiped don with WD40 after use).

I'm wondering if perhaps one of the chemicals is causing this, perhaps paint stripper or hydrochloric acid (for the pool). All the chemical are kept in supposedly sealed containers. There is no pool chlorine.

Can anyone suggest which specific chemical(s) might be causing this, and is there a better way way to protect the tools after they have been cleaned up? The shed is waterproof but everything is exposed to any atmospheric dampness (in Sydney).

Thanks

BobL
12th June 2011, 12:36 PM
What is the floor made of?

I found a big difference in corrosion between storage in a shed where the floor was made of paving and one with a sealed concrete floor. The paved floor shed was always much damper than the concrete floor

So called air tight containers are rarely that. As atmospheric pressure rises and falls air tight containers act like little pumps and leak out small amounts of contents.

Solvents should be no problem, water based paints are a small problem but the acid will be your biggest problem. Hydrochloric acid really needs to be stored in glass - it slowly leaks through plastic over time :o - certainly enough to corrode tools.

I don't think of WD40 as a long term anti corrosive, it's prime purposed is as a water repellent (WD stands for water displacement) but unfortunately it evaporates away over time.

RETIRED
12th June 2011, 12:42 PM
Use Inox, it hangs on a lot longer than WD40. It evaporates as Bob said.

Normanj
12th June 2011, 01:08 PM
Thanks for the suggestions. The shed floor is pavers laid on earth, so its no sealed. I'll review how the hydrochloric acid is stored. Perhaps we need to put the bottle in an outer container to reduce any leakage.

Thanks again

soundman
12th June 2011, 01:43 PM
Mate I guarantee you that moisture will be the #1 offender, any other chemicals may be a contributer...but the moisture will be the problem.

you have 3 solutions and they will all only be partial cures on their own.

seal the floor.....this will reduce the amount of moisture commin up from bleow.

Ventilate..preferably forced ventilation....this will reduce the amount of moisture in the air inside a large Dc computer fan and a small solar pannel would be a sart if the shed is not close to power.

Heat, this will dry the air and reduce condensation, and you need less than you may think...a 100watt bulb may be sufficient but that is poloitiacly incorrect isn't it.

I have done quite a few outdoor concerts and stuff over the years...when we tarp up over night even inside tents, we always put a 60 to 100 watt lamp under the tarps to keep the condensation away.

there is also a 4th...insulate.......if the inside of the shed is full of warm moist air...as the temperature dropps water will condense on all metal surfaces.

but you have to face facts that sheds are not clean dry enviroments......you need to cover anything you do not want to corrode...even a single sheet of news paper can make a huge difference.

cheers

BobR
12th June 2011, 02:54 PM
Since moving to Laurieton 18 months ago I find that any tools left out for any length of time start to rust. Anything in a drawer or cupboard seems to be OK. Mine is an insulated shed. So as Soundman said, cover everything up.

BobL
12th June 2011, 03:01 PM
Thanks for the suggestions. The shed floor is pavers laid on earth, so its no sealed.
I agree with sound man. That will be 90% of your problem. You could consider relaying the pavers over plastic


I'll review how the hydrochloric acid is stored. Perhaps we need to put the bottle in an outer container to reduce any leakage.
Put the acid container and a piece of polished steel inside a plastic bag - no need to seal the bag - just fold the top over. Place another piece of the polished steel as far away from the HCl container and plastic bag and compare the corrosion after a few weeks.

Bushmiller
12th June 2011, 04:24 PM
My garden shed (I do my woodwork elsewhere) is used to store a range of tools..



Norman

Am I right in assuming that you don't have a better place to store your tools such as where you do the woodworking? That would be the simplest answer.

If some tools are not used frequently a temporary measure, until you do any of the forementioned suggestions, may be to coat them with a heavy oil. I remember at school when we were the last class of the term our job was to go around every tool and wipe a coating of oil over them, because sure as hell if we didn't they had a coating of rust on our return. I don't know what oil it was, but my memory is it was similar to engine oil in thickness.

I understand the problem you have in that my shed has an open side:oo:. However, I do have another area to store the majority of my tools.

Regards
Paul

Normanj
12th June 2011, 04:36 PM
Bushmiller,

Thanks for this. You are correct. I do my woodworking in a brick carport which is covered but open. These tools come indoors when the jobs is done. The garden shed is used to store the things I mentioned and while its enclosed, it essentially just sits on pavers so it stays dry but is not insulated, and I don't think its practicable to do this. On a damp day like today the air in the shed will be damp. Can't be helped.

Form all the answers so far it seems I need to improve the storage of the hydrochloric acid and perhaps the water-based paints and then protect the tools with Inox.

Off to bunnies in the morning I think. I'm there so often nowadays if I miss a week they call to ask if I'm OK :-)

Master Splinter
13th June 2011, 12:54 AM
The number one cause will be proximity to hydrochloric acid - chlorides are very good at promoting rust. Scrub the rust off well, rinse with plenty of water to remove residual chloride ions, dry with a good wipe of paint thinnners, and apply your choice of inhibitor.

I like the lanolin based stuff.

Lawriet
13th June 2011, 10:24 AM
Absolutely the pool chemicals are your problem. As the chlorine evaporates, it mixes with the moisture in the air to form Hydrochloric acid and rusts your tools and metal. Big problem in Qld. Look at where they store the pool chlorine at your local hardware store - no where near the tools and usually in an outside pergola area. Pool chlorine and Hydrochloric acid should be in a dry but ventilated spot. I don't even store the chlorine in my shed for this very reason.

wun4us
13th June 2011, 11:17 AM
Absolutely the pool chemicals are your problem. As the chlorine evaporates, it mixes with the moisture in the air to form Hydrochloric acid and rusts your tools and metal. Big problem in Qld. Look at where they store the pool chlorine at your local hardware store - no where near the tools and usually in an outside pergola area. Pool chlorine and Hydrochloric acid should be in a dry but ventilated spot. I don't even store the chlorine in my shed for this very reason.

Perhaps this may throw more light on the subject?

hydrogen chloride

hydrogen chloride, chemical compound, HCl, a colorless, poisonous gas with an unpleasant, acrid odor. It is very soluble in water and readily soluble in alcohol and ether. It fumes in moist air. It is not flammable, and the liquid is a poor conductor of electricity. Hydrogen chloride is prepared commercially by the reaction of sulfuric acid with sodium chloride (common salt); niter cake, a mixture of sodium bisulfite and sulfuric acid that is a byproduct of nitric acid manufacture, is sometimes used in place of sulfuric acid. Hydrogen chloride is also produced as a byproduct of the manufacture of chlorinated organic chemicals. It can be prepared directly by reaction of hydrogen and chlorine gases; the reaction is very exothermic and takes place readily in sunlight or at elevated temperatures. Although anhydrous (water-free) hydrogen chloride is commercially available as a high-pressure compressed gas in steel cylinders, most of the gas produced is dissolved in water to form hydrochloric acid (see acids and bases (http://www.factmonster.com/ce6/sci/A0802335.html)), a commercially important chemical. Pure grades of hydrochloric acid are colorless, but technical grades, commonly called muriatic acid, are often yellow-colored because of impurities such as dissolved metals. Most hydrochloric acid produced has a concentration of 30% to 35% hydrogen chloride by weight. The major use of hydrochloric acid is in the manufacture of other chemicals. It is also used in large amounts in pickling (cleaning) metal surfaces, e.g., iron before galvanizing. It reacts with most common metals, releasing hydrogen and forming the metal chloride; with most metal oxides and hydroxides it reacts to form water and the metal chloride. Hydrochloric acid is also used in small amounts in processing glucose and other foods and for various other uses. Concentrated solutions are strong acids and highly corrosive. Hydrochloric acid is not an oxidizing agent but can be oxidized by very strong oxidizing agents, liberating chlorine gas. In dilute solutions of the acid the hydrogen chloride is almost completely dissociated into hydrogen and chloride ions (http://www.factmonster.com/ce6/sci/A0825403.html). A solution containing 20.24% hydrogen chloride by weight is azeotropic, boiling at a constant temperature of 110°C at atmospheric pressure. Hydrogen chloride also forms monohydrates, dihydrates, and trihydrates that are liquids at room temperature.


Also, the gas used in WW1 was chlorine gas, hydrochloric acid being a by product of chlorine.:oo:

Normanj
13th June 2011, 02:48 PM
Thanks for all the suggestions. I think I have enough now to mitigate the problem. The point about pool chlorine is well made although, as I said, I don't store pool chemicals in the shed, though I do have a bottle of hydrochloric acid, allegedly sealed.

There's not much I can realistically so about the floor so the plan is:

1, Get an extra level of containment for the Hydrochloric Acid
2. Clean up the tools and then apply some Inox with Lanolin
3. Look at ways to possibly further protect metal surfaces.

Thanks again for all the advice.