[Cob] Re: was tree-sculpted...now tractor cob

[Shannon C. Dealy]

On Wed, 14 Jan 2004, Barbara Roemer and Glenn Miller wrote:

[snip]
> people with tractors.)  On bare dirt, at least in the summer, it's pretty
> easy to see and feel with the tractor when you're down to the soil level
> rather than in your mix.  It follows that careful measuring/mixing will
[snip]
> Spending plenty of time mixing will assure integrity of the mix.
[snip]

People have used a variety of techniques for mixing cob with tractors,
skid loaders, and other equipment and the problem (at least with the skid
loader / tire mixing approach), is that with the tires doing the mixing,
they will cut right down to ground level and below, without any way for
you to tell, and the water from the mix will work right into the surface
of the ground.  The result is that all your careful measuring of
ingredients will be blown if this occurs, additionally, the longer you
work the mix with the skid loader, the worse the problem becomes, so if
you are trying to get a good uniform mix, you will likely make the problem
of extra soil in the mix much worse.  The basic lesson here is if you are
going to mix your cob with the tires of the machine you are using
(particularly if they are going to be counter rotating the way skid
loaders do), on bare earth, work out your ratios first, then mix all your
ingredients dry using the bucket to scoop and dump repeatedly to get the
dry ingredients (sand, clay, straw) as thoroughly mixed as possible, then
add the water and mix as quickly as possible to minimize churning up
the soil below.

Shannon C. Dealy      |               DeaTech Research Inc.
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