[Cob] COB MIX DESIGN

[Amanda Peck]

Welcome to the coblist!  I've read a LOT more than I've done, but I believe 
that every time you start work on a new site, or with new clay/sand, you get 
to do tests to figure out how your mixtures are going to work--and tests to 
see what's going to look nice as a wall surface.  So, reinventing the wheel 
is not exactly what you're doing.

Charmaine Taylor uses a lot of sawdust, one of the Australians has been 
testing gypsum in his mixes. Colored sand, mica dust, different colored 
clays, and different coloring agents FOR clay--are used a lot in the surface 
plasters, as are some mosaic effects.

If you're thinking low-impact and sustainable, then that makes a difference 
in what you're going to want to use.  Unfortunately, around here, there's no 
more lime kiln on Lime Kiln Road.  And unless I want to log and bulldoze a 
fair amount of my woods, I get to buy my clay--the mostly likely building 
site is probably silt a good ways down.

And if you're talking your base sand/clay/straw mix that someone is likely 
to want to work with their bare hands or feet, I for one would avoid the 
crushed oyster shells (Guy Clark does sing about tearing up his car's tires 
on them oyster shell roads) and the recycled glass.

Ms Taylor's bookshop is www.dirtcheapbuilder.com and there are links from 
there to what she's doing, other people's home page, and so on.

...............................
Michael LaRoche wrote:

I am thinking about reinventing the wheel so to speak by experimenting with 
materials in cob mixes.

I am looking into adding different materials to a cob/earthen mix and test 
it for durability and structural characteristics.

Some of the materials I am gathering include: sawdust, vermiculite, perlite, 
different sizes/courses of sand, color pigment, colored sand, peatmoss, 
bark, lime, plaster of paris, crushed oyster shells, small pebbles, recycled 
glass, and so on...

I will be building the test clods in 12" or so cubes for material ratio 
tracking.

thoughts/comments/advice?

Michael LaRoche
Floyd, VA



_______________________________________________
Coblist mailing list
Coblist at deatech.com
http://www.deatech.com/mailman/listinfo/coblist

_________________________________________________________________
Say “goodbye” to busy signals and slow downloads with a high-speed Internet 
connection! Prices start at less than $1 a day average.  
https://broadband.msn.com (Prices may vary by service area.)