[Stoves] re-bar size and durability

[rbtvl at aol.com]

Re-bar quality might be quite variable around the world.  We have made grates with a frame of 12 mm re-bar and cross pieces of 6 mm re-bar.   For the particular re-bar we find in Tanzania, the 6 mm re-bar melts in perhaps 6 months.   the 12 mm is very durable.   

We make a "fire box" in our factory mostly out of 2 mm steel sheeting.  We have removed fire boxes that were in use for a year or a year and a half  and located all the places where there was bending or deterioration.    We now weld pieces of 12 mm re-bar into our fire boxes in the manufacturing process to reinforce the places that will bend or fail first and I think this way, have probably added a couple of years to the life of the stoves.

At the conference in Cambodia I was upset to hear, in answer to my question,  the EPA people say there would not be measuring properties of used stoves because it would be "too expensive".    If we don't study our used stoves, we will fail to really change homes.   Of course, women will return to old ways if our stoves don't last.   The Maasai women cook for 30 hours a week, for maybe 7 people.   Durability is very important.   I worry that a lot of the small portable stoves with thin metal parts that we see on display at conferences are not going to last.

Re-bar is very useful to us.  But it has to be used thoughtfully.  And you might have to use thicker re-bar than you thought ideal.

bob

Robert V. Lange
Maasai Stoves and solar
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