Friday, October 01, 2010

Barrel o Lime

We began our Lime Slaking project the other day. The major part of the plaster for the outside of the house (and, we've decided, for the kitchen and bathroom inside) will be lime putty, instead of clay.

To make lime putty, we took 5 50lb bags of hydrated Type-S lime, and mixed it into a barrel of water. This is what 250lbs of lime look like in a 55 gallon barrel, with a little water on top:



They say, the longer this stuff sits and soaks, the better it is. It could be a year before we get this stuff on the outside of the house. I hope it's only a couple of weeks before we start working it into the bathroom and kitchen walls.

By the way, since it was hydrated lime, we didn't really have any of the safety concerns that they always warn about. We prepared for them, but it didn't boil, or give off heat, or act like acid, or anything.

1 comment:

Muddy Gurl said...

Hi- no you will NOT ever have trouble with exothermic reaction with a bagged hydrate-- that ONLY occurs when' hot lime' is being processed by the manufacturer.
It is almost impossible to buy any amount of hot lime to burn (calcine) yourself in the USA - because of the danger in untrained builders handling it. I know specifically of a builder in Canada, and his explosive accident with putting hot lime into a drum that was still moist-- it literally blew up, started a fire! Remember your chemistry, always add lime to water... " do as you oughta, add acid to water"

You are just SOAKING the hydrate lime, slaking already happened before you bought it.

It sounds like you have more lime than water in the drum. My advice is to add as much water as you can, and leave at least 4-6" of water, on top, otherwise the lime will begin to air cure, and harden back to limestone. And having just moistened lime is not giving you the nice mellow putty you are seeking. Better to use 2 or 3 drums, and keep a lot of water in them. The lime water you will get is always useful as a wash, a pre-spray to wet between plaster layers, add to clay plaster, etc. you cant hurt the lime, and it gives you real protection from air curing too early.

if the lime on top is crunchy, & lumpy anyway, just grind it up and use it as aggregate, because it is now limestone again, not a bad thing, but will not soften again for you.

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