Pin Gage Rust Prevention?

Calcium carbonate is limestone. Barn lime is used primarily to reduce slipping on concrete. It is not commonly used as a desiccant.

Years ago we used calcium chloride as a desiccant. It can be oven dried and reused. Cobalt chloride was often mixed with it, as it turned from blue to red when it had absorbed water and was a visual indicator of the need for rejuvenating.

More recently, silica gel is used as it is less corrosive. It is the stuff in the little packets that come inside electronic equipment packages. It can also be rejuvenated by heating in an oven and an indicator like cobalt chloride can be added for a visual end-of-use indicator.

I personally do not rely on desiccants for humidity control. They are OK when fresh but as they absorb water, they are functioning as a constant humidity source. We used them in the lab but we had a regular routine to replace them with fresh desiccant on a weekly basis. We also used desiccators sealed with silicone grease to prevent an exchange of humid air with the interior. Any desiccant which is exposed to outside air will continue to pick up moisture until it is saturated.

A better approach is to use a small oven to maintain a temperature well above the dew point. This is the method used to keep welding rod dry. We also used it to keep phenolic microspheres used in epoxy composites dry. An insulated box with an incandescent light bulb will maintain a temperature of more than 100ºF and is hot enough to prevent any condensation (we used an old refrigerator). 70% RH at 70ºF is only about 25% RH at 105ºF.

If used to prevent corrosion of metrology instruments, you will have to allow them to come to room temperature before use.
 
Even though I live in Wisconsin where the dew point can be near or even below zero F in the winter, my dehumidifier still runs year round. My basement is only 600 sq ft, but I still have a 70 pint dehumidifier set to maintain 35% humidity. I have never found rust on anything in my basement and I make no efforts at rust proofing. Even a fresh clean weld does not rust.
 
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Also in southern Wisconsin, I run the dehumidifier from late May into November. Central A/C also rempves a lot of the moisture when outside temperatures warrant running it. The rest of the year, the wood furnace keeps the humidity low due to its draw of fresh air and keeping the basement warm. I also have about 600 sq. ft. but the 100 y.o. foundation is porous so moisture is constantly coming in. I monitor RH at four different locations in the house so I can do a cold weather dehumidifier activation if needed. The RH ranges from 40% to 65% and I do not have rusting problems.
 
I am fortunate to have recently acquired a complete set of Meyer Pin Gages.
From .011” to .500”.
All the pins are accounted for and they are pristine.
The paper used to absorb moisture is Cortec vapor barrier.
I am a believer. No rust after at least 35 years.8C344D04-6D54-41F1-8EE7-9F04C0FA5917.jpeg248B432B-9AD2-4EB9-8ABC-CFABF0CEE833.jpeg
 
J--I have the Meyers pin gage set and also that Bondhus (sae) hex set.
 
I had sets of pins sitting in the basement for years . Every once in a while I would open the boxes and spray them . They looked great until I pulled the pins out of the bottom box . They were rusted from pulling moisture out of the concrete . :mad: They are since gone .
 
I keep my precision tools in a heated space in winter, no rust problems, but, that's California.
 
Yes, calcium chloride that’s what I meant:oops:
 
I use VCI paper for tools well enclosed in boxes. For steel tools stored in drawers or on shelves in my shop, I use a mixture with 2 parts ATF, 5 parts mineral spirits, and 2 parts anhydrous lanolin. Heat the lanolin gently and until it is completely melted. Add the ATF and mix in. Add the mineral spirits and mix it in. Do not use flame heat. I shake it before each use, but do not know if that is really necessary. I apply a thin wet coat to tools and parts mostly with an old toothbrush, and then let it dry. It leaves a thin coating that is unnoticeable. I have never seen any rust on anything so treated in my unheated shop in Sacramento, Calif. I would not trust it on anything stored exposed outdoors without testing it first on something unimportant.
 
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Where do you get anhydrous lanolin?
What does it do the atf doesn’t?
I know atf is loaded with detergents
Mineral spirits, hugh
I know we get foggy cold days in Sacramento so your recipe should work in most climates.
 
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