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

[Shannon C. Dealy]

On Thu, 15 Jan 2004, SANCO Enterprises, LLC wrote:

[snip]
> and Shannon wrote
>
> <heavily snipped>
>
> < (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. >

> My dear friend---it would appear that you have not used or have
> experience with a skid steer, tractor or loader for mixing.  I have a
> 2-1/2 yd loader that is not a skid steer and works extremely well and as
> noted by Barbara and Glen, you can control the depth of the cut.

Paul, you have misunderstood my statements, as I noted previously, there
are many techniques that people have used for mixing (and I attempted to
qualify my statements to the approach I am talking about), and you are
apparently not familiar with this approach (which I have personally
used for a number of batches, and which is how all the cob in the building
I am sitting in was mixed).  This approach has been used by a number of
people (though in every other case I am familiar with they mixed on a
cement/concrete or asphault base) and gives a better mixture consistency
than the pure bucket mixing approaches that I have seen to date, which is
why I use it, however, that does not mean that there aren't other
approaches to a pure bucket mix that don't work better than the ones I am
familiar with.

> Typically, the spinning of skid steer tires, gives the illusion that
> they are the ones doing the mixing.

With the approach I am talking about, the skid steer tires are pointedly
used for mixing the cob, by running the machine up on top of the pile and
spinning around continually through the mix, only using the bucket to walk
the machine out when it high centers, and to push the pile back together
as it spreads out.  When doing this, the machine and tires are effectively
a giant blender, very effectively churning the cob mixture.

> It is the bucket that is used to do
> the mixing by breaking up the clumps with the weight of the machine,
> then folding--continuously-until you get a uniform mix.

This is a different approach.

> As for water running out of the mix, quite the opposite is true.  By
> using the wieght of the machine and down pressure on the bucket, the
> clay creates a seal or barrier between the work and base material that
> it was placed on.

This is very much going to depend on your base material, though with the
mixing approach you describe I would expect it might be less of a
problem than with the approach I use (given the soil and moisture here, I
would not assume that it will work better here without trying it).

> If you keep the blade out of the barrier, your water
> tends to want to run off if you have a heavy clay content-absorption is

This is going to depend very much on the soil you are working on and it's
mositure content prior to mixing (and you are in a much drier place than I
am), on the ground where I am working, the simple act of turning a skid
loader (because of the way their skid steer mechanism works) makes a
significant cut into the surface of the ground (breaching the "barrier"
you describe), which creates ruts and high spots right in the middle of
the mixing area that even with your bucket mixing approach will have to
result in either picking up soil from the mixing site, or else leaving a
substantial amount of mix on the ground (essentially filling in the ruts
with the cob and leaving it).

You need to keep in mind that there are many approaches to mixing, and
many different soils for working on, the soil here is basically very
soft most of the year, so any equipment working on this ground outside of
perhaps one or two months in late summer is going to potentially have
problems with carving up the ground.

Shannon C. Dealy      |               DeaTech Research Inc.
dealy at deatech.com     |          - Custom Software Development -
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