Cob: Shannon's Building Project

[Shannon C. Dealy]

On Fri, 16 Mar 2001, Rosemary Lyndall Wemm wrote:

> Thanks, Shannon.
> 
> The whole thing looks cute ;-)  One suggestion for next time around  - use
> Becky Bee's suggestion for jar windows:  Tape two same type jars together to
> form a dirt-tight seal.  Paint or lime-wash the outside walls of the jars
> white so that the cob doesn't darken them and the light shines through them
> better.  [Leave the ends clear, of course.]  Then you'll only need to wash
> the outside ends after you've cobbed them in place.

I am familiar with the above techniques, unfortunately, I couldn't use
them.  The walls on this building are very thin for cob because building
codes force me to keep the building footprint under 120 square feet.  In
order to maximize the interior space, the walls are very thin, only about
twelve inches maximum, so doubling up the jars by putting them end-to-end
would have left the second jar sticking way out of the wall, instead, I
opted to make the cob matrix around the jars very thin (as viewed from a
wall thickness perspective), so that less light is blocked by the cob
between the jars.  The cob matrix around the jars probably only extends
into the wall four or five inches from the outside of the building.  I
also used the largest jars I could find in order to minimize the amount of
area blocked by the cob, most jars in the big window are either quart or 
half gallon sized.  As far as paint or limewash, while I had lime on hand
and did consider it, I didn't have any obvious "free" sources for it, 
so using it would have violated the rules of the building.  It is however,
good that you pointed these things out for others on the list whose
buildings don't have my silly rules and building code limitations.

> You could try out my earlier idea of creating glass jar spaces by first
> cobbing around bits of large size polypipe. When the cob shrinks, pull them
> out and replace then with glass jars set in fresh cob.

I don't remember this one, but have you tried it?  When I was doing some
cobbing around a few individual jar "mini windows" during wet weather late
in the fall, it wasn't setting up fast enough to keep from collapsing the
interior opening where the jar didn't quite reach, so I stuck in another
jar (sticking out of the wall) as a temporary measure just to keep the
holes open, and when I went to remove the extra jar a couple weeks later
after that section of the wall dried, I found that I couldn't.
Eventually I will get them out, either by chipping away the cob, or
repeatedly soaking the area until the cob softens enought to remove them,
but given this experience, I would be concerned about counting on being
able to remove the polypipe from your suggestion above.

> Another idea is to color the ends of your glass jars with the craft paints
> used for fake stained glass windows.

I had thought about just using jars of different colors to make it more
decorative (green and brown are readily available, though generally not
in large sizes), but for this building I was more concerned about letting
in enough light since there will be no interior lighting, so I decided to
go with only clear glass.

> When I get my workshop set up [by next month, I think] I am going to
> continue my experiments with methods of cutting glass bottles.  My current
> idea is to clamp a power drill in a vice, put a flat pad in the chuck,
> attach [superglue?]a bottle cap to the flat pad, screw glass bottles into
> the lid, support the bottles in a mitre box, attach a glass/ceramic "blade"
> to a hack saw, rest the hack saw in the ninety degree angle slot of the
> mitre box [with the bottle set at the right length], turn on the drill to
> low speed, put gentle pressure on the hack saw and wait until the bottle is
> sawed neatly through...   I'll let you know if it works in a couple of
> months.

I have a book called "Build-it-Yourself Science Laboratory" by Raymond
E. Barrett which provides a technique for cutting glass bottles consisting
of scoring the bottle with a glass cutter, then using a nickle chromium 
wire mounted in a wooden frame and heated red hot by passing an electrical
current through it to cut the bottle where it has been scored.  Better
wear goggles, and make sure you don't electrocute yourself!  This book has
been out of print for some time, but you may be able to find it at a good
older city library, or possibly at the library in a local school if you
can get access.  I liked the book so much when I was in Junior High School
almost thirty years ago, that I got the library to order a copy for me to
buy.

> Meanwhile,
> 
> is your creation open to the cob-mudding public?

I'm not sure that there is anything worth seeing that the pictures don't
alreay show.  I have more pictures, but they don't really show much that 
the others don't.  Unfortunately, something went wrong with the pictures
for the foundation work and that roll came out blank.  In any case, if
someone wants to see it, let me know and we can set something up.

>  if so, where can it be viewed?

a couple miles Southwest of Philomath, Oregon, USA, which is about 90
miles South of Portland, Oregon.  Of course if you are in this area, you
would probably get more out of a visit to Cob Cottage Company which is
about 80 miles Southeast of my building site, and has alot more to see.

>  and for what price?
>  in what commodity?

If the grass is tall enough, I might set you to work harvesting grass or
making grass twine for the roof structure :-)


Shannon C. Dealy      |               DeaTech Research Inc.
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