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| The Windlass Kit One of the first tasks for our castaways will be to get useful items from the wreck to the place chosen for shelter. This assumes the wreck is washed up on or near the beach. How can the survivors move heavy pieces of material and equipment up a sandy beach? What other problems would they encounter attempting to move materials over both hard and soft sand? A windlass kit (Fig.1 opposite) could be used with children from P3 to P6. In the first instance pulling loads by a handle, and progressing to driving the windlass by pulley and electric motor. All the bits necessary for manual operation are supplied with a kit, as are full construction notes. If need be, we can supply additional parts to motorise the windlass. Once one model has been made, it should be easy to make others. We suggest that you use our design at first before going on to suss its many possible variations. |
Shipwreck Kits It should be noted that the diagrams are only intended as indications of the designs. We reserve the right to make changes in the interests of continuous product improvement! Windlass kit with all parts ready for assembly including teacher's notes. Includes :
£3.00 incl. postage & VAT Windlass kit upgrade with electric motor. Includes :
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| Simple Pulley Block A simple pulley block can be made with a cotton reel, some scrap corrugated plastic (e.g. Corriflute), three wire nails and a length of 25mm ribbon or tape. Figure 2 shows some construction details. Safety note - the pointed ends of the nails should be removed or flattened before the children handle them. Use a 'Junior' type hacksaw or a couple of taps with a hammer. The ribbon or tape should be attached as shown in the sketch. A system of two pulleys should in theory give a force advantage of 2. Alas this does not work in practice. Why not? |
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| Factory Kit This next is a further kit of parts to build a Victorian factory pulley system. Well - perhaps to build an example of changing output speed using pulleys. For an impression of the finished model see Figures 3a and 3b. Once again we offer all the parts necessary to build your first model. We will be delighted to hear of modifications or new designs, or even how easy or difficult the kit was to assemble.
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Factory kit with all parts ready for assembly. Includes :
£3.50 incl. postage & VAT |
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| P1/P3 Forces and their effects :
| Difference between pulling through water and sand on the beach. Difference in stopping on land and on water, why? Using a windlass to move heavy loads. (A system similar to that used in an old fashioned well). |
| P4/P6 Forces and their effects :
| Following on from above investigate the difference the position of the winding handle has to the effort needed to move the load. Positional difference is the distance from the axle. Perhaps a larger diameter wheel? Change the windlass to a block and tackle. Move load over a variety of surfaces. Forcemeters to measure effort required to move load. Introduce friction. Why it is there and how it can be reduced? Try rollers, wetting the surface, wheels or a sledge. Simple pulley systems for speed changes. |
| P7/S2 Forces and their effects :
| From above continue with block and tackle and forcemeter, units of force. Levers as force magnifiers. Simple pulley systems for speed changes. |
Technology in Society :
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Using the Design Process
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| P1/P3 | Moving loads with the aid of a single pulley wheel or windlass. |
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| P4/P6 | Follow on from P1/P3. Building structure to support pulleys in moving loads. Design and build a motorised windlass. |
| P7/S2 | Design and build both a manually operated and motorised crane using pulley blocks. Design and build a motorised buggy using pulleys to effect speed control. |
