Cob: Smooth Cob Walls

[Mafalda Stock]

On Mon, 1 Oct 2001, nigella1 wrote:

 > Hello everyone, nigella here, I was a member sometime ago and had to leave
 > due to time restraints. Anyway , I am back :)
 >  I have a question. I have seen some cob structures (pics) that are smooth
 > as glass and some that had straw sticking out everywhere. I imagine at least
 > some of this is for intentional texture but how do you get the straw pieces
 > smoothed off , if you want them off?

The smooth as glass look in photos is almost certainly a cob plaster
over the surface of the completed wall, and straw sticking out everywhere
is the normal look of a freshly completed unplastered wall.  To achieve
this look, a cob plaster mix is made using fine fibers such as manure
and/or really short straw fibers.  Usually, it will be a high sand mix and
all ingredients (sand, clay, straw) will be run through a sieve to remove
any large chunks and other junk.  When you apply the plaster you can use
a thin piece of flexible plastic (such as the cut out center of a cottage
cheese container lid) to float the surface, the longer you work it, the
better it will look.  You may want to experiment with this a bit, I
working from memory and it has been several years since I did any cob
plastering.  You could search the coblist archives for related postings,
it seems like I wrote one or two on plastering:

     http://www.deatech.com/natural/coblist/

If you have trouble accessing the web site, let me know, I'm having
trouble with my primary internet feed, and at times about 1/4 of the net
has connection problems.


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