Cob Re:

[SANCO Enterprises <Paul & Mary Salas>]

"Janice.Exline[xline"@thegrid.net] wrote:

Snipped.

> Does anyone have a formula for earthen plasters that HAS been pushed by a
> pump during application..

We finally got our custom designed pump up for a test run two weeks ago and
used just pit run soil with some stones as large as 1" in the mix.  The
material passed through the pump just fine and the texture of the of the
mixture was like butter--smooth and thoroughly mixed. We wanted a  a #2 slump
and were able to stack the pump mix 16" high. Not formula per se, just added
enough water to get the material to go through the pump.

The original pump design works great and the 4 cyl Isuzu diesel has more
power that is need for all functions. After re-assembly, we only had one
problem, a hydraulic hose sprung a leak.  Not bad for building a machine from
scarp and surplus including the hoses and fittings.

We will be running a longer test today for a group from the UNM materials lab
and NSF staff who are supporting the project.  We will screen the material
just to see what we get this time.

> Have received numerous request for using our mortar gun to apply earthen
> plasters and am concerned with plugging the pump using native materials
> that haven't been screened etc....

Using a Mayco piston hydraulic such as yours will probably not work well
especially with stones over 3/8".  This is the primary reason we decided to
build our unit using a 6" cavity pump rather than a "piston-hydraulic" that
rams the material through the hose.  The cavity pump pushes or conveys the
material through the pump rather than ramming against a ball check.


> are there any bagged clayproducts that are economical enough to use ???

>From our experiences with "piston hydraulic" pumps, the mix has to be fairly
rich to keep the hose lubed--4 sack is min for this pump.  Try a closed loop
test with a soil mix that you want to use.  If you have a short 10' whip
piece of hose, just run the material right back into the pump and see if it
will pump it.  Worst case you only have a few cubic feet of material to clean
out if the pump packs.

We purchased a new digital camera that down loads directly to the PC--haven't
used it yet, but at least now we can get some photos of our machine out on
the web.

Paul Salas
SANCO Enterprises, LLC
Albuq. NM