[Cob] Lime Slaking

[robert at edgewaterNW.com]

Thanks to everyone who responded to my info request on the technical 
aspects of slaking quicklime to make lime putty. I appreciate the time 
you spent responding. One of the respondents asked why slake lime when 
it is possible to buy hydrated lime and just mix it up with water and 
presto- lime putty and another  respondent suggested that it was too 
dangerous to slake lime-just use hydrated lime.

So- why bother slaking quicklime?- Jane Schofield wrote a booklet 
called "Lime in Building" - a practical guide.
There is a short mention of hydrated lime- aka "bag lime".  To snip a 
few points out of the two paragraph discussion- "although this has some 
uses, and is better than no lime at all, it is inferior to properly 
made lime putty for various reasons ranging from its particle size 
(lime putty is much finer) to its fast degradation in less than ideal 
storage conditions,... it is unreasonable to expect lime mortar to work 
effectively if its setting properties are exhausted before it is used". 
"Hydrated lime has regularly been used as an extender or filler in 
cement mixes, but its use as the principal binder is limited". Even 
with proper preparation " it will not be as good as proper lime putty 
and will be unsatisfactory for limewash".

BTW- I made another 100 gallon batch and it worked out well.

Robert in the upper left corner