[Stoves] Glazed Maputo Ceramic Stove

[Crispin]

Dear Friends

See: http://bioenergylists.org/en/mcsglazed

This is a picture of a glazed MCS 200 (200 mm in diameter) which was made 
this week in Maputo.

The idea is that the stove should not look 'like a ceramic stove' but more 
like a casserole or a serving dish, something perhaps one would find in a 
kitchen rather than out in a shed.

There are several things that need to be improved.  The powdering of the 
ingredients needs to be improved before mixing.  The charcoal in particular 
is not fine enough (cavities too big I think).

The mix was formed on a potter's wheel which is definitely not in the 
manufacturing plan - too wet.  It is an interim measure to get some 
prototypes for marketing surveys.  It should be damp-formed in a press which

will increase density and strength and reduce cracking.

The little 'wings' that the grate sits on are too plentiful - only 4 to 6 
are required.  They are attached after the potter is finished.  Because it 
dried very rapidly (2 days instead of 5-7) they were added a little too 
late.  This led to cracks appearing at the wing-body joints.  Fortunately it

is very strong but still, it is something that can be timed better.

I like the 11 hole grate. We made some with 9, 11 and 13 holes to look for 
differences in performance.  The centre hole is slightly larger than the 
others.

I believe the glazing was fired to 1050 degrees.

The pattern happens to match a dish and plate set.  Conceivably it could be 
made to match other kitchen plate sets for a standard fee (i.e. a marketing 
gimmick).  We might still add handles if research shows they are needed.  I 
measured a maximum temperature at the outside bottom of 110 degrees.  The 
air preheat seems to have been over 200 degrees, and the maximum temperature

at the top of the body was 220 on the outside.  The light colour of the 
glazed one will raise the temperature by reducing radiation losses.  This is

good and bad.  We could put an insulative sleeve around the upper 
sction....lot of possibilities.

Regards from the summer sun in Dakar by the sea.
Crispin 

See more images of the MCS 200 at:
http://bioenergylists.org/en/mcs_8_23_2006