{"product_id":"bridge-school-project-kit","title":"Bridge School Project Kit – Grade 9","description":"\u003cp\u003eA laser-cut wooden kit for the Grade 9 bridge school project: a tied-arch bridge 41 cm long, with two arches, a road deck and twine hangers that carry the deck up to the arches. It shows exactly what a Grade 9 structures report has to explain: the arches are pushed, in \u003cstrong\u003ecompression\u003c\/strong\u003e, while the hangers and the deck are pulled, in \u003cstrong\u003etension\u003c\/strong\u003e.\u003c\/p\u003e\u003ch3\u003eWhat's in the box\u003c\/h3\u003e\u003cp\u003e38 pieces, packed flat:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e3 mm MDF sheets × 4 (200 × 300 mm each), with 26 laser-cut parts, every part labelled\u003c\/li\u003e\n\u003cli\u003eWooden dowels × 10, for the deck joint, the arch feet and the top bracing\u003c\/li\u003e\n\u003cli\u003eCotton twine × 2 (1.35 m each), for the hangers\u003c\/li\u003e\n\u003cli\u003eWood glue × 1 · sandpaper × 1\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eThe 26 parts are two deck plates, two end walls, four side rails, four splice plates, four legs, four beams, four arch halves and two crowns.\u003c\/p\u003e\u003ch3\u003eHow the bridge carries a load\u003c\/h3\u003e\u003cp\u003ePut a weight on the deck and the twine hangers carry it up to the two arches. An arch turns that load into a push along its curve, so the arches work in compression, and their feet push outwards at the ends of the bridge. In a tied-arch bridge the deck holds the two feet of each arch together, like the string of a bow, so the side rails work in tension and the stands only have to carry the weight straight down. The four dowels across the top brace the two arches together, so they cannot lean or buckle sideways.\u003c\/p\u003e\u003ch3\u003eHow to make the bridge, step by step\u003c\/h3\u003e\u003cp\u003eEvery kit comes with a short 3D animation of the whole build, so a learner can watch it once and get it right the first time. It takes the build in eight steps:\u003c\/p\u003e\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeck plates.\u003c\/strong\u003e Lay the two deck plates end to end, road side up, with the straight edges meeting in the middle.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEnd walls.\u003c\/strong\u003e Push an end wall onto each end of the deck so its teeth sit in the deck slots, with a drop of glue.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSide rails.\u003c\/strong\u003e Fit the four side rails onto the deck fingers, tabs on top and the single hole at the bridge ends.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMiddle joint.\u003c\/strong\u003e Put a splice plate outside and inside each rail joint, then push four dowels right across the bridge.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStands.\u003c\/strong\u003e Slot two beams into two legs to make each stand, and set the stands under the bridge ends.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eArch halves.\u003c\/strong\u003e Hold an arch half outside each rail end and push a dowel through arch, rail and leg, across the bridge, at both ends.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eArch crown.\u003c\/strong\u003e Close each arch with a crown on the inside and push the four top dowels through both arches.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTwine hangers.\u003c\/strong\u003e Tie the twine at the first arch hole, zigzag between the rail tabs and the arch holes, and tie off. Repeat on the other side.\u003c\/li\u003e\n\u003c\/ol\u003e\u003cp\u003eLet the glue dry for about an hour before you load it. The full walk-through, with the structures theory for the write-up, is here: \u003ca href=\"\/blogs\/guides\/grade-9-technology-project-bridge\"\u003ehow to build a bridge for the Grade 9 project\u003c\/a\u003e.\u003c\/p\u003e\u003cp\u003eThe whole build is also on the \u003ca href=\"\/pages\/arch-bridge-assembly-video\"\u003ebridge assembly video\u003c\/a\u003e page.\u003c\/p\u003e\u003ch3\u003eTesting it\u003c\/h3\u003e\u003cp\u003eOnce the glue is dry, load the middle of the deck a little at a time with something you can count, such as coins or small books. Watch where the bridge moves first, and stop as soon as anything starts to bend. Write down the load each time: that is your test result.\u003c\/p\u003e\u003ch3\u003eSize when built\u003c\/h3\u003e\u003cp\u003e41 cm long, 19 cm high and 16 cm wide, with a road deck 14.4 cm wide.\u003c\/p\u003e\u003ch3\u003eMaterials\u003c\/h3\u003e\u003cp\u003eEvery wooden part is cut by laser from 3 mm MDF, so tabs and slots meet within a fraction of a millimetre. Each part is labelled. The wood glue is for the end walls, and the sandpaper is for easing any tab that feels tight.\u003c\/p\u003e\u003ch3\u003eTest-fitted before it's packed\u003c\/h3\u003e\u003cp\u003eWe build every kit once by hand before it is packed. If a part doesn't fit, that's on us, not on your learner.\u003c\/p\u003e\u003ch3\u003eBuilt for the CAPS Technology syllabus\u003c\/h3\u003e\u003cp\u003eDrawn in our own workshop and checked against the CAPS Technology syllabus for Grade 9, where bridges come under Structures. See all \u003ca href=\"\/collections\/grade-9-technology-projects\"\u003eGrade 9 Technology projects\u003c\/a\u003e.\u003c\/p\u003e\u003ch3\u003eCommon questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhere can I buy a bridge school project kit?\u003c\/strong\u003e Right here. Order online and we deliver to homes, schools and shops across South Africa from our workshop in Gauteng.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat type of bridge is it?\u003c\/strong\u003e A tied-arch bridge, also called a bowstring arch: the road deck hangs from two arches and ties their ends together.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill it help with the Grade 9 design brief of a bridge?\u003c\/strong\u003e The design brief and the specifications are the learner's own, but the \u003ca href=\"\/blogs\/guides\/grade-9-technology-project-bridge\"\u003ebuild guide\u003c\/a\u003e shows how to write both, with this kit's measurements as the example.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it the whole Grade 9 project?\u003c\/strong\u003e It is the model. The design brief, the drawings and the write-up are still the learner's own work, and the \u003ca href=\"\/blogs\/guides\/grade-9-technology-project-bridge\"\u003ebuild guide\u003c\/a\u003e explains the forces in plain words to help with that.\u003c\/p\u003e\u003ch3\u003eDelivery\u003c\/h3\u003e\u003cp\u003ePacked in one flat box in Gauteng and shipped to homes, schools and shops across South Africa and Namibia. Standard delivery anywhere in South Africa is R65. Delivering to Namibia? \u003ca href=\"https:\/\/wa.me\/27782020786?text=Hi%20Slotbok%2C%20I%27d%20like%20to%20ask%20about%20delivery%20to%20my%20town.\" target=\"_blank\" rel=\"noopener\"\u003eWhatsApp us\u003c\/a\u003e with your town for the cost. Buying for a class or a shop? \u003ca href=\"https:\/\/wa.me\/27782020786?text=Hi%20Slotbok%2C%20I%27d%20like%20to%20ask%20about%20class%20sets%20and%20wholesale.\" target=\"_blank\" rel=\"noopener\"\u003eAsk about class sets and wholesale\u003c\/a\u003e.\u003c\/p\u003e","brand":"Slotbok","offers":[{"title":"Default Title","offer_id":50519519002838,"sku":null,"price":279.0,"currency_code":"ZAR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0838\/8191\/8678\/files\/01_Slotbok_Arch_Bridge_hero.jpg?v=1793637504","url":"https:\/\/www.slotbok.co.za\/products\/bridge-school-project-kit","provider":"Slotbok","version":"1.0","type":"link"}