age of lime

[hesam]

does anyone know for how long the lime is aged before being used in plaster?
some company's claim the lime they are using is aged up to five years,but
i don't believe they actually do that.
i'm trying to make my own plaster ,so im gonna need to know that .
and what facilities would i need to store the lime?
does anyone know that?

[Ted]

Look up a guy named Dean Farago. He's from Australia and his family has been making their own plaster and scagliola for generations.

Hope that helps!

[rogerhattman]

There are some variables, but if you are working from modern pulverized quick lime 3 months should be plenty. You need to keep the lime from freezing and from drying out.

[The Plasterers Arms]

[urruela]

The plasterers who want to dedicate to this trade have to have foresight and provision of slaked lime enough so that we can undertake several projects. The Cal must be off at least 6 months before its use, if you are years better, therefore calculate the consumption that we will need is very important. Large consumers make the off in rafts made of bricks with grout or burnishing of reinforced concrete, in a is where the off,n another raft, after leaving screened sleeping the time indicated.
The proportion of calcium oxide (quicklime) must be of 1 kg per 2.5 liters of water. Once made the mixture and with the above precautions is removed with a blender again and again, still hot must be stirred from time to time. This is important because in this way helps to break down the small is that can lead to problems in the future, in addition to facilitate subsequent screening.
The next day when the cal is cold is sifted with a strainer or sieve of 40 meshes per cm2, approximately.
If the shutdown will be made in metal container with the heat certainly lose the paint protection, therefore it is not advisable to leave many days since you will probably release we pigmente oxide and the pure white of the cal. The sieving we will do this on a plastic or steel always that this lacquer and not release rust, or well in rafts.
We will leave until the next day, when already has distilled the calcium hydroxide (slaked lime) the water will be floating, proceeding with care not to remove remove the water, leaving at least a fourth above, to keep it from drying out and unusable.
Once off the cal and sieved the keep, frost-free and of the sun, covered tightly so you don't lose water and dry, although all forms it is advisable to check once in a while you don't need that fourth of water, if that water reduces is sign that continues to absorb or rehydrating. Excess water should not be throwing, as that helps us to be used again in another off, or as we shall see later has other utilities.

The lime is a caustic product by which the burning organic and inorganic tissue, it is necessary to save a series of precautions while avoiding the dangers. For the shutdown of the cal, at which time we have to take more precautions, it is indispensable even for little amount, use gloves, mask, goggles of plastic covering the eye and enough clothes that don't want to miss a possible contact with the quicklime.
If by chance we manchamos with dust to manipulate the sacs best cleaned with a dry cloth as soon as possible, while avoiding the eyes with your hands, if this happens by accident, clean again and again with water, even disappearing the irritation may cause some injury.
The hydration of lime will never get done in plastic container or glass, always in iron drum or raft. The plastic is not suitable, at least the majority does not withstands a temperature of 95 ºC, it is best not to take risks. The container may burst and imbibe of lime with the consequent burns. It is ideal to moisturize to 3 to 3.5 L of water by one kg of lime, still better the excess that the defect, the excess water will have time to remove it.
There is always that pour the water before the calcium oxide (quicklime) once we have the water in the container will be incorporated into the cal little by little, stirring gently so that it does not splash and caring that is not click heap in the water that we dump the cal.
Once the cold lime and for other processes we will have the same precautions as any mortar, by seeking to use gloves for handling. As with the cement is not desirable that it is in contact with the skin on the hands, after work there is to be washed well. Wash your hands with wine vinegar greatly reduces the effect alkaline, after a few minutes are washed with soap and water.
When it reaches a splash to the eye it can be washed with water thoroughly, although at the beginning seems not to have effect, you have to do it, the time may produce irritation and even pain.

I hope this is helpful Hesam.

Oscar urruela.

[hesam]

thanks you guys , this sure was helpful .
there is something i forgot to ask in my previous post:
can you estimate (roughly ) the age of the lime ?
i mean you examine the lime and you say ,its been aged for approximately a year or whatever.is that possible ?
cause i found an italian supplier that sells aged lime for a more or less
resonable price . they say the lime they are selling is aged for two years.

[1st year apprentice]

A great thread. great intro to me in my limited experience with this stuff, lol
Plasterers Arms allways a great contributer to this media.

Thanks peeps Brian

[CarpenterSF]

I don't have any trouble believing that some companies have lime aged 5 years. I have maybe 50 gallons of hydrated lime that's been soaking for 6 or 7 years now. Every once in a while I have a small project where it's the right thing to use, and it is incredibly sticky and plastic and wonderful. And plastering is just a side part of my business, so I have no trouble believing that companies committed to the business have much longer times, with lime slaked by them. When I finish a bucket I start a new bucket soaking.

As far as how long freshly slaked lime takes, I don't know, but hydrated lime gets pretty plastic after a couple months.

[artesano]

Hesam,

I don t know of any way to tell the age of a lime putty. The best thing would be, see how it performs for your application.

The questions I would ask are;

- Does it have good workability? when you add up to 3 parts sand to it does it still work nice and smoothly on your tools?

- Does it hold its water against suction? When you apply it to a moderately moistened absorbant substrate does it immediately dry and become unworkable, or does it stay a little moist and allow you to smooth it.

- How durable does it become after curing? If you do a test wall and cure it for a month or two, does the plaster become sufficiently hard and durable?

- Are there little explosions that happen in your plaster finish in a month, 6 months, a year.... This is the main reason lime putty was traditionally soaked for so long. Often limes have impurities like magnesium inherent in the stone that slake much more slowly than the CaO , If you use the putty before some of these "slow" particles have reacted, they could do so on your wall. These are known as pits or pops and not good! If you have a very pure high calcium lime putty, you will most likely avoid this problem.