[Cob] Alum and Soap over horizontal Lime Plaster surfaces?

[littlehouseantiques at att.net]

-------------- Original message from "Quinn" : -------------- 

> Wouldn't the soap just... re-suds up and wash away? 


Uh, no, I don't think so.  I use regular ol' liquid dish soap in my 
acrylic water based paints (to extend drying time) and none of it 
has ever "re-suds up".  

> Ingestion of 30 grams (1 ounce) has killed adults. Huh. And you 
find it right next to the allspice.  

Well, I would hope no one would take a bite out of my cob bench - 
lol!  But the point about folks being sensitive to alum (eyes skin, 
etc.) would likely be a problem on a bench where skin would come in 
contact with it....

BUT I was reading earlier today about a patent that was obtained by 
a fella back as early as 1876 (for a mixture that included alum that 
was put on canvas tents and uniforms to waterproof and prevent mildew 
& mold) and there were reports even way back then that the fabric 
treated with this stuff did irritate the hands/skin of some soldiers...
however, the pertinent point was that the fabric didn't irritate anyone 
until they went to cut the fabric when mending, etc.  So, perhaps the 
alum/soap mixture on a cob bench would NOT irritate anybody as long as 
it was properly maintained and not allowed to dry/crack/flake, etc.  

Kathy