MANUFACTURING THE DONKEY CART AND AMBULANCE
1. Introduction
For poor people trying to escape poverty, lack of mobility can push them further into physical and economic isolation. Practical Action Sudan works to help poor communities in North Darfur State increase their access to the facilities and services including markets that are essential to improving their lives, opportunities and economic growth.
Picture 1: The water carrying donkey cart
Following the path forged in the Eastern Sudan Integrated Technology Programme, the development of intermediate means of transport (IMT) devices such as animal drawn carts has been promoted. Around 40 metal workers in North Darfur have been trained so far in the use of wheel-making sets and production of carts, trailers and wheelbarrows together with spare parts. Practical Action Sudan has supported the creation of a manufacturer society for the production of these IMTs and maintained distribution channels for the finished products through village development committees. These committees have their own funds for purchasing IMTs and selling them on to local farmers through a credit system. Practical Action has also been helping with the development of the donkey cart ambulance and has worked with
Picture 2: The Donkey Cart Ambulance
Practical Action, The Schumacher Centre for Technology and Development, Bourton on Dunsmore, Rugby, Warwickshire, CV23 9QZ, UK T +44 (0)1926 634400 | F +44 (0)1926 634401 | E infoserv@practicalaction.org.uk | W www.practicalaction.org ____________________________________________________________________________________________________________ Practical Action is a registered charity and company limited by guarantee. Company Reg. No. 871954, England | Reg. Charity No.247257 | VAT No. 880 9924 76 | Patron HRH The Prince of Wales, KG, KT, GCB
Manufacturing the donkey cart and ambulance
Practical Action
manufacturers in both North Darfur and Damazin. Many people living in rural areas find it very difficult to access health centers or hospitals when they are ill. It is hoped that the donkey cart ambulance can act as a means of safe transport to these facilities when no motorized vehicles are available. This manual aims to give useful information to local fabricators and organizations that support them to help them make these intermediate means of transport. Although we have tried to give accurate information there is more than one way of making some of these components and their dimensions may need to change depending on what is available in the local markets.
2. The Wheel Jig
2.1 Background Access to wheel manufacturing technology enables workshops to set up their own facilities to produce a range of good quality wheels from standard steel sections. Wheels can be made to take bicycle, motorcycle, car and solid rubber tires and to suit a range of low-speed vehicles such as handcarts, bicycle trailers, wheelbarrows and animal drawn carts. An assembly jig technology has been introduced by Practical Action Technology to ensure that the wheels can be made to a consistent quality. The equipment can be made in a workshop that has competent metalworking skills and basic tools for cutting, welding, drilling and grinding steel. It can be readily adopted and used by other workshops with basic metal working facilities to produce good quality wheels at low cost and on reach a small to medium scale of production. 2.2 Parts List
Part Material and Notes No off Length (mm) 1000 475 180 40 50 90 120 60 160 Width or cross section (mm) 50 x 50 50 x 50 50 24 30 Depth / Wall Thickness (mm) 4 4 4 4 4 20 12 OD 25 M20 Diameter (mm)
Picture 3: Manufacturing the wheel jig during a workshop in Damasene
A B C D E F G H I
Angle iron (jig base) Angle iron (jig base) Flat Plate (rim clamp base) Flat Plate (rim clamp support) Flat plate (Backstop) Round bar (Backstop) Round Bar (Handle) Pipe (Screw support) M20 Bolt (and nuts)
1 6 8 8 8 8 8 8 8
2
2
Manufacturing the donkey cart and ambulance
Practical Action
J K L M
(Vice screw) M8 Bolts (and nuts) M30 Centre Screw (and 2 nuts) Round flat plate (Locking Disc) Hub Clamp Handles
16 1 2 2
25 160
M8 M30
116
16
2.3 Instructions 1. The purpose of the jig is to hold the wheel rim concentric to the wheel hub so that the wheel spokes can be welded in place. The first task is to the cut the angle iron to the appropriate sizes shown in the material list (Parts A and B). 2. Once the material is cut a number of 8mm clearance holes need to be drilled in each piece of angle iron for the 8 wheel clamps (see diagram 3) which will allow for varied size wheels to be made. It is important that these holes are drilled accurately. The holes in Part A can be drilled first, with the first hole being 115mm from the end. After that there should be 6 more holes 50mm apart. This is also the case for part B where you should start at the end which has not been cut at 45 degrees when marking the holes.
Diagram 1. Hole positions for the jig base
The table below shows the position of the holes and the different size wheel rims which can be produced (ID) depending on their position (hence the holes in diagram 1 are 50mm apart.
Wheel Rim (ID) 150mm 200mm 250mm 300mm Hole position from end (for wheel clamp) 415mm 365mm 315mm 265mm Hole position from end (for wheel clamp) 265mm 215mm 165mm 115mm
3
Manufacturing the donkey cart and ambulance
Practical Action
4. These parts now need to be arranged as in diagram 2 where they should be welded in position. As can be seen from this 4 pieces of Part B should be cut at 45 degree angles. 5. The next stage is the making of the 8 rim clamps which will hold the wheel rim. Firstly 8mm clearance holes need to be drilled and equal distance apart (150 mm). These holes will allow the jig to make different size wheels.
Diagram 2. Plan view of wheel jig base Part B cut at right angle x4
Part A x1
Part B with two straight end x 2
6. The heads of eight 20mm bolts are cut off and the handles (Part G) are welded at one end. 6. A 20 mm nut is then welded to the end of the tube (Part H) 7. Following this, Parts E and F are welded together and then welded to Part C (see tech drawing WJ – 02 for positioning dimensions). 8. The rim clamps are now ready to be screwed in place on the frame. Obviously in the same position on each leg although it will be quite apparent if one is in the wrong place. 9. The central locking bolt can now be put in the centre of the frame. First of all a hole is burned in the metal with the welder that allows the 30 mm threaded bar (Part K) to fit inside. The threaded bar is then welded in position (90 degrees to the base).
Diagram 3. A 3-D Model of one of the 8 wheel rim clamps Part F Part H Part G Part E
Part D Part I Part C
Diagram 4. A 3-D Model of the Hub Clamp Part K Part M Part L (Note: K, L and M are welded together)
4
Manufacturing the donkey cart and ambulance
Practical Action
10. The final phase is the making of a small device capable of locking the wheel hub concentrically. This of course will depend on the size of the wheel hub you are using. In the cart outlined in this manual the OD of the bearing is 92 mm. Therefore a circular piece of material is required with an OD of 90 -91mm and a 20mm clearance hole in the middle for the locking thread.
Picture 4: A completed wheel jig
This will probably need to be prepared on the lathe unless suitable size washers can be found. This disc is then welded concentrically to the nut. This needs to be made twice to lock the hub concentrically at the bottom and at the top. Finally the handles are welded to the top locking disk as shown in diagram 4. In pictures 4 and 5, instead of using M30 nuts, specially manufactured round bar material has been threaded; as stated in the introduction some of these components.
Picture 5: A completed wheel jig from above (Note: The diagonal parts of the jig base should be at 45 degree angles as shown in the technical drawings).
there is more than one way of making
Note: Please see Technical Drawing Number WJ - 01 and 02 for more details.
3. Manufacturing the wheel
3.1 Parts List
Part Material and Notes No off 2 1 1 Length (mm) 1300 1240 100 Width or cross section (mm) N/A 100 Depth / Wall Thicknes s (mm) N/A 3 8mm (4mm for the bearing surface) 4 5 External 100 Diameter (mm) 15
A B C*
Mild Steel Round Section Bar Mild Steel Flat Plate (Rim) Mild Steel Tube – * see method NO 6 before starting Mild Steel Right angle section (spokes) Mils Steel Flat Plate
D E
5 5
150 60
50 x 50 50
N/A N/A
5
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