[Cob] Soap & Alum Recipe

[Megs Testarmata]

I'm rather intriqued by the thought that soap scum may actually
have a POSITIVE use!  And since I can't seem to find anybody
with hands on experience or any specific alum/soap recipes, seems
like some good old fashioned experimenting is in order.

Wandering off to don the lab coat now....

Kathy

Well, Kathy, here's a recipe for you.  I was down in southern New Mexico
last spring at a Kutunza Natuaral building workshop and we were introduced
to a master plaster man, Pat Taylor, who is devoting his life to restoring
old buildings on both sides of the border in traditional lime plaster.  He
has learned much from the meistros of Mexico.  Right now he is working on
Socorro Mission just a little south of El Paso and welcomes volunteers.  I
spent a few days there, learned alot. His assistant gave me this recipe in
English and Spanish, but I am not sure they ever used it.  I do remember
Pat saying that the type of alum required couldn't be found in this
country and had to come out of Mexico.

Impermeabilization of lime plaster roofs:
Cut slices of lye soap, the smaller the better.
Boil 100 liters (26. 4 gallons) of water in metal container (such as 55
gallon drum) and add 16 kg (35.5 lbs) of sliced soap stirring until it
completely dissolves.
Apply hot solution with the mop over the entire roof surface; allow to dry.
Grind the rocks of alum (alumbre in Spanish)with hammer.
Following the same boiling procedure in another metal container, boil 100
liters (26.4gallons) of water and add 8 kg (17.8 lbs) of ground alum.
Apply in the same manner over the dry coast of soap.
Six applications of each of the coats should be applied, ending with alum
coat.

That's it.  Megs in Nome, Alaska