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Demotech News


News Sat Feb 10 (2007) -- Fri Apr 22 (2016)
News Tue Jan 25 (2005) -- Mon Sep 25 (2006)
News Fri Jan 09 (2004) -- Tue Jan 25 (2005)

Technology for Democracy

Tue Dec 16 (2003)

True democracy needs some help from technology. Democracy is about making your arguments heard, also when your arguments differ from mainstream ideas. Or worse, when the media are used for propaganda by ruling groups.
Technology should give backing to people who differ with the official policy. So technology should back up the people who differ with the 'Anti Terrorism policy of the OVSE.
The idea behind the DemoCamp units is to offer relevant technology (= tools) to people who want to make their arguments heard. A crew from Landbouwbelang used the DemoCamp units to do so. People along the route of the OVSE-demonstration, as well as people on television could watch it.

The message

Publishing

Display page # 1

Broadcasting

Display page # 2

For me, working for Demotech, this demonstration offered the opportunity to see and record how the DemoCamp units worked in practice. The crew of Landbouwbelang had no difficulty in assembling the tower. To carry the tower proved to be easy and facile to do by three people.
From the video footage I'll take snapshots to make a manual, available in this website. Demotech's video instructor Erik Holthuis will help to edit the tape to make a video as an other tool to assist instruction.

How it works in Maastricht

Mon Nov 24 (2003)

A group of squatters use a deserted factory in Maastricht to put some pleasure and social responsibility back into this world. The pleasure comes from the parties they organize in this factory, that proves to be very fit for this kind of joy. See Landbouwbelang for details.

They wanted to find out if they could empower their social responsibility with the DemoCamp-units. Last Saturday I brought them some of the sticks and cross wires that have been laying unused for a far to long time. It really gave me good feel to see how easy they mastered the composure of towers and tents with this system. They demonstrated again how much fun it is to dance with a ten meter high tower or to create a spacious shelter. Neither took it long for them to see where and how they could make good use of the DemoCamp-units at short notice.

One technical construction detail proved to be inadequate: the interconnection of the four half cross wire parts in the center with a piece of cord. This asked for a better solution and such a solution offered itself soon (details coming). Swift action, swift results, that is how it works in Maastricht.

Constructing the tower

Up in the air

Dancing ten meters high

BrickStove testing

Mon Oct 27 (2003)

Blue and reddish gas flames where sucked into the flame tunnel

At the workshop of Hans Baarslag in Wierden, the BrickStove waited for a test. New to be tested were three items:

  • the lining of the fire box made from thin stainless steel sheet (0,5 mm),
  • the new set up of the conical funnel, the 'catch' where the wood from the container gets stuck, while sliding into the fire box,
  • the ash tray, also folded from sheet metal, that takes part in guiding the burning gassified wood into the "flame tunnel".

Thanks to the link we got from Sasha I now understand better the two phases of wood burning: first the gasification of the wood, followed by the burning of the gas. Air (oxygen) for such secondary burning is still available in the gas mix or streams in through a second opening.
Actually these two phases could well be observed through a glass window: wood, while it was burning and smoking remained stuck into the catch. From time to time charred peaces fell off, lining the ash tray with burning charcoal. Blue and reddish gas flames where sucked into the flame tunnel. (see top picture)
The steel sheet lining for the bricks, the shape of the 'catch', the ash tray and the entrance to the flame tunnel, all seemed to function as foreseen. However not so the in-flow of air.

So we reconsidered the idea of pre-heating air, similar as is done in steel furnaces. As the BrickStove is build now, cold air from outside is pre-heated when it flows along a metal separation in the flame channel. It then flows under the ash tray and enters the fire at the front, the place where the window is positioned.
This functions only partly. Because the fuel (wood) container still has a very rough fit in the top of the BrickStove, a part of the air sucked in by the ventilator, leaks in through this bad fit.

rough scheme of the new setup

Joel Fransen, Demotech's new intern from the Design Academy in Eindhoven, suggested to make this accidental air leak the one and only entrance for fresh air.
This is a nice kind of break-through idea, upsetting the present basic set up, but giving another simplistic layout in return. With Hans I planned to build a second stove in this way (see rough scheme of the new setup).

  1. Fuel container, filled with anything solid that will burn.
  2. The conical funnel, the 'catch' where the wood from the container gets stuck, while sliding into the fire box.
  3. Flame tunnel and interior space where the burning gasses transfer their heat to the stone exterior.
  4. Exhaust to ventilator. Forced draft sucks in the air at the fuel container, blows it outside.
  5. Brick exterior heats up while the fuel container feeds the fire. Its outside radiates its heat outwards for a long period after the fire is extinguished.
  6. Top of metal sheet can be removed for inspection and repair.

Roller development

Sat Oct 18 (2003)

Prototypes: strips, rings, disks

The test rig of the rope pump has many new components. In fact only the electric engine, its drive disk and the big two meter diameter wheel, that it drives remain from the first setup. As the big wheel is not round at all (it has 12 corners), it needs a roller to keep the tension on the rope steady, specially the unloaded part, moving back to the electric engine.
In the old setup a sort of lightweight pulley folded from thin aluminum sheet did the tensioning. This worked fine, but the pulley was to difficult to make.

How the strips fit into the disks

Together with Bram de Vries I tried to simplify the making of this tensioning roller. We started out with a cylinder of bamboo slats, woven into a strip (left in picture). We found this too heavy and side ways flexible. For the bearings we had a woven construction in mind. Sideways stability was achieved with less bamboo by tying it zigzag on two rings wound from wire. Stability was perfect, but the woven bearing was difficult to make. (middle position, woven bearing removed).
Amazingly easy it proved to be to insert the bamboo sticks in a zigzag way into disks cut from a bucket. Six small square holes and an shallow slot in the bamboos did the trick. The lower picture shows this detail
Puncturing the disk in the middle with a piece of wire results in the creating of the bearing as well as of the axle.

Games with heat and air

Sun Oct 12 (2003)

Mail contact with Sasha Mrkailo, Serbia brought me to this link on small gassifying woodstoves:
First of all it shows the feasability of the idea of forced draft through the oven, as tests show. This encourages, as Demotech explores this principle in experimenting with the Brick Stove.
Second it shows how helpfull it is when information exchange really centers on the issue at stake. It saves everybody a lot of valuable time.
The picture indicates how the draft through this small stove results in gassifying wood and burning this gas in the top part of this stove. It looks like a very smart game with heat and air. How it works is explained in this article.

Layout test

Sat Sep 20 (2003)

Why *This is a layout experiment to find out how the layout should be of the listing of the records in the category page. I want to see how it looks if I use the same method as with making the layout of News. so please do not look at the text that is just a dummy
* Progress within poverty depends on improving conditions for education for 1 billion students world wide.
* Poverty reduces the capacity of young people to study at home. Cramped interior space used by too many and insufficient interior lighting are negative factors to be overcome.
How * Education ask for time to study. Four hours each day after sunset can be used for study with a proper reading light, called the NightReader, that fits conditions of poverty.
* A box with batteries to which two LED's are attached is placed on the page or paper to be read. The LED's only illuminates a few lines of text, not attracting insects.
* A NightReader can be constructed with the help of a construction manual by its user or people around from local scrap material.

Second layout test

Sat Sep 20 (2003)

Why *This is a second layout experiment with a smaller picture, to find out how the layout should be of the listing of the records in the category page. I want to see how it looks if I use the same method as with making the layout of News. so please do not look at the text that is just a dummy
* Progress within poverty depends on improving conditions for education for 1 billion students world wide.
* Poverty reduces the capacity of young people to study at home. Cramped interior space used by too many and insufficient interior lighting are negative factors to be overcome.
How * Education ask for time to study. Four hours each day after sunset can be used for study with a proper reading light, called the NightReader, that fits conditions of poverty.
* A box with batteries to which two LED's are attached is placed on the page or paper to be read. The LED's only illuminates a few lines of text, not attracting insects.
* A NightReader can be constructed with the help of a construction manual by its user or people around from local scrap material.

Getting ready for Cameroon

Sun Sep 14 (2003)

A NGO in Cameroon contacted Demotech by mail. They had a sincere interest in many of the designs, related to rural as well as to urban conditions. It would be nice to be able to serve these people better. Still not even the old manuals of the rope pump are properly visible in 'Make It'. It just is an amazing amount of work, taking a amount of time destructive for other projects that should be done as well.
However on behalf or these people in Cameroon I organized the 'Make It'-manual for the construction of the Bathroom/Toilet unit better. This became possible after the reorganization of the images was done. Also my answer to the demand of Leonora and Petz for a bullets in 'How' and 'Why' extends now into 'Presentations'.
The demand of these intern girls resulted into a sceme to present a few short items marked with bullets in 'Why' and 'How' , these two fields as presented for each record in the 'Category' page. Together, these items can be read as a summary that is covered more extensively in "Why' and 'How' as visible in the design page. This proves to be a workable structure.
The same structure now applies also to the first page of a presentation, such as Manual for the Bathroom/Toilet unit. Each chapter of such longer manuals is in short described in one sub-record of 'Presentations', hyper-linked to this page. I made sure the chapter descriptions together could be read and understood as a summary of the total manual.
The net result should be easier navigation through Demotech's website. Our new contact in Cameroon is the first who can tell us if this works. I sincerely hope they will use our discussion page to air their findings!

How to find out what works and what does not work? Only to try gives an answer. Around 1986 Demotech tried to speed up instruction around improved wells and water pumps in Ghana with the Mobile Training unit.
We bought a DAF-truck to get going .. but got nowhere. No support or support that halfway redoing the electric wiring thought of something better. Now the DAF-truck at last is on the road again. I gave it away to a nice guy in exchange for his promise that he would support Hanna's Senegal project with some free transportation when needed.

Drifting apart, creeping together

Mon Sep 08 (2003)

The big cleansing operation of images that relate to Demotech projects and design did not stop at renaming and ordering pictures. It was a painful discovery that the description of designs in our FileMakerPro database had got far behind the description of the same designs in the our website. To make the confusion even bigger, names given at an earlier state did not match the present development. Even worse it became, when names and descriptions in fact partly related to other records.
By now, I have sorted out most of this mess. Giving names to designs is important as they should be descriptive. Each name should be composed out of two short words. The two-letter code that has to be drawn from the first letter of these two word components is used to indicate and sort related images. When the logical name of one design resulted in a letter code that already was taken, I had a problem. It took all my fantasy to think of a different logical name, leading to a two-letter code that was still free. Most of the letter code combinations found at last look familiar, but I am afraid some of them will never stop to confuse me.
To prevent this mess to return, I asked Marc, Demotech's web designer, if the FileMakerPro-database of designs could interact with the MySQL-database of our website. He expects that will not be too difficult to achieve. If this indeed will become possible it will make a big difference. The FileMaker database contains more that a hundred descriptions of designs. Only twenty of them have been transferred to the web. The transfer would made eighty more designs accessible. Though this is of course what I strive for, in practice all this new information asks for translation into English, better pictures and bringing text up to the present level of development. This is a massive amount of work that can only be done over time.
The big advantage however is that work on any record only has to be done once, instead of the confusing two times in the present situation.

Dull administration

Wed Aug 27 (2003)

This website asks for an enormous amount of pictures to clarify its content. Hundreds are already uploaded to the computer of Demotech's provider, AS-Hosting. Many thousands will follow. Many recent mistakes make it clear that a simple and clear system is needed first to size, then to name and finally to store the images.
Coordinating work with volonteers like Leonora and Petz, who produced a flood of most beautiful photo's, also ask for a system that is very easy to explain, as such workers assist Demotech only for a short time, be it days or weeks.
Today I cleaned up only the beginning of the mess that came into being as such an administrative system had not yet been perfected. This is the work drill from now on:

  • Every picture worth to be kept is cut back to a square and saved sized 1000 x 1000 or 500 x 500 pixels, at 300 dots per inch and in a JPEG-format.
  • All such pictures get a name, starting with two letters, indicating the name of the related record for this design initiative. (see picture) They are stored in alphabetical ordered files. A to D, E to J, etc. Later pictures wedge in without a problem.
  • Of each picture a Gif copy is made in the size 120 x 120 pixels, 160 x 160 pixels and 250 x 250 pixels. Apart from the gif-extentions, its name remains exactly the same. Exceptions of this rule should remain seldom. During the process of sizing down color, sharpness and contrast are adjusted. These Gif-pictures are stored in a different file, but in the same alphabetic division.
  • Only when an image is needed for the web page, it is uploaded and properly embedded in the content. When the content is changed, superfluous pictures should be removed.

    This dull administrative work will also lead to conflict with Google, that does not like changes in file names. All by all it is work, a lot of work and frustrating work. I expect there will still many mistakes be made, but once this system grinds itself into our genes, life will be slightly easier.


  • News Thu Aug 14 (2003) -- Tue Jun 03 (2003)
    News Thu May 22 (2003) -- Mon Mar 17 (2003)
    News Mon Mar 17 (2003) -- Wed Dec 04 (2002)
    News Thu Nov 28 (2002) -- Mon Oct 21 (2002)
    News Fri Oct 11 (2002) -- Tue Aug 27 (2002)
    News Tue Aug 27 (2002) -- Mon Jul 01 (2002)