Project 3 — Working with Wood and Bamboo

Wood is one of humanity's oldest materials. In India it is in the carved pillars of old temples, bullock carts, the wooden ladle stirring dal, school benches, cricket bats, fishermen's boats and oars, and the handles of kitchen knives. Many famous buildings are made largely of wood: the Hidimba Devi Temple in Manali, Rumtek Monastery in Sikkim, Vishrambaug Wada in Pune, and the Padmanabhapuram Palace in Tamil Nadu, one of Asia's largest wooden palaces, about four centuries old and spread over some six acres. Wood is also used for houses, furniture, packaging, paper and artwork, and in some areas as fuel.

Wood and bamboo are still chosen even when concrete and steel are available. Houses built with them stay cooler in summer and warmer in winter because wood does not conduct heat easily. They are strong for their weight, which is why bats, hockey sticks and even small bridges and playground equipment use them.

Is wood renewable? Trees can be replanted, so wood is called a renewable resource. But it is sustainable only if we plant at least as many trees as we cut. In some places, such as high Himalayan slopes, trees grow back very slowly or not at all, so a cut forest may be lost for good. The wisest practice is to use wood from trees that have completed their natural life, rather than felling young trees. This respect for the earth is old in Indian thought: a well-known hymn of the Atharva Veda asks that whatever is dug from the earth may grow back quickly, and that we may not wound her vital places.

Substitutes for solid wood

• Engineered wood is made by pressing and gluing wood layers, particles, fibres and sawdust, often from recycled wood. Plywood is made of thin wood sheets glued with their grain at right angles; MDF (Medium Density Fibreboard) is made of fine wood fibres pressed with glue.
• Bamboo is not a tree but a giant, perennial grass. When cut, it sprouts again from its underground stem and grows very fast. India has many species, growing in most of the country except the hot Rajasthan desert and cold Ladakh desert, with the most in the north-eastern states.

In this project you will work with softwood, plywood, recycled wood or bamboo, so that your learning costs the forest as little as possible.

Wood from different trees behaves very differently, so a carpenter's first decision is always which wood for which job. Wood is broadly grouped as hardwood or softwood.

Hardwood comes mostly from broad-leaved trees. It is usually dense, heavy and strong, and lasts long. In India:

• Babool and mango wood are used in construction, window frames and flooring.
• Jackfruit wood is used for furniture and small items such as pooja stands and handicrafts.
• Teak (sagwan) resists water and insects, so it is used for ships, outdoor furniture and fine doors.
• Sal and sheesham are used for heavy furniture and beams.

Softwood comes mostly from cone-bearing trees with needle-like leaves, such as pine and deodar. It is lighter and is used for light furniture, shelves and packing boxes. Fast-growing eucalyptus (nilgiri) is widely grown for paper pulp and poles.

The names describe the usual feel of the wood, though there are exceptions. For your project what matters is that hardwood is difficult to cut and shape and needs sharper tools and more skill, while softwood is easy to saw, plane and finish. Bamboo is also easy to work. Plywood and wood recycled from old furniture or packing crates are good beginner choices too.

The fingernail test. To check a piece quickly, press your thumbnail firmly into the surface and drag it along. If it leaves a clear dent or scratch, the wood is soft. If it leaves almost no mark, it is hard. Try it on several objects at home and school: a pine packing crate, a teak door, a plywood shelf, a mango-wood chopping board. Test on a hidden spot so you do not spoil a finished surface.

Grain. Look closely at any plank and you will see lines running along it. These are the wood's fibres, called the grain. Wood splits easily along the grain and resists across it. Sawing, planing and sanding all go more smoothly when you work with the grain, and joints and screws hold better when placed with the grain in mind. Before starting, also check your piece for cracks, loose knots and nails left in recycled wood.

Good work begins with knowing each tool's job and using it safely.

Materials you will need include softwood or bamboo, nails, screws, wood glue or synthetic resin adhesive, sandpaper, varnish or paint, cardboard and cellophane tape.

Safety rules

• Work only with a carpentry instructor, teacher or local carpenter supervising, and watch each tool demonstrated before you use it.
• Clamp the work in a bench vice or with clamps. Never hold a piece in one hand while sawing or drilling with the other.
• Keep both hands behind the cutting edge, and cut or plane away from your body.
• Wear safety goggles while sawing, drilling and sanding, and a mask against fine dust.
• Carry saws and chisels with the blade pointing down; never run with tools.
• Check that hammer heads are tight and blades are sharp; a blunt tool needs force and slips more.
• Varnish and paint give off fumes: use them in an airy place and keep them away from flames.
• Keep the workspace tidy: sweep away shavings and offcuts, and return every tool to its place after use.

A good habit is to set out only the tools you need for the next step. A cluttered bench is how chisels get knocked off and fingers get cut.

Before making anything, watch someone who does it every day. A visit to a carpenter's or bamboo worker's workshop shows you how raw material becomes a chair, a door frame or a basket, and how many decisions a craftsperson makes along the way.

Before the visit, prepare your questions so you can use the time well. Decide who in your group will ask, who will write and who will sketch. Ask permission before taking photographs.

Record basic details: the name of the carpenter or workshop, how many people work there and what training or qualification they have. Many carpenters learn as apprentices; others train at an Industrial Training Institute (ITI).

Questions to ask and observe

• What kind of work is done here: furniture, doors and windows, house construction, repairs, bamboo crafts?
• Which woods do they use for which products, and why? How do they decide?
• Where does the wood come from? Do they use plywood, MDF or recycled wood?
• Which hand tools and which power machines do they use?
• How do they go from an idea to a product: measuring, drawing the design on the wood, cutting, joining, finishing?
• Which joints do they use most often?
• What safety precautions do they take, and have they ever been injured?
• How do they price a product?

Watch carefully for things nobody tells you: how the carpenter checks a measurement twice before cutting, how a saw is started with short gentle strokes, how offcuts are saved for small jobs, how sawdust is cleared away.

At a bamboo workshop, ask how bamboo is selected (mature culms are stronger than young ones), how it is dried and treated against insects, and how it is split into strips for weaving.

After the visit, write up what you learnt in a table with two columns: question and observation. Add a sketch of one product with its parts labelled. Note three things you would like to try yourself, and one thing that surprised you. This record will guide your own design in the activities that follow.

Most wooden or bamboo objects are made of several parts assembled together. The place where two parts meet is a joint, and the right joint decides whether an object is wobbly or lasts for years. Here are four common joints.

Why does the lap joint beat the butt joint? Glue holds best on long-grain faces and poorly on end grain. A butt joint mostly glues end grain to side grain, so it pulls apart easily. A lap joint presses broad faces together, giving much more gluing surface. A mortise and tenon adds a mechanical lock: even without glue, the tenon cannot slide out sideways.

Bamboo joints. Round, hollow bamboo is often joined by lashing with twine or cane strips, by fitting one pole through a hole in another, or by pegs and bolts through drilled holes.

Studying an object. Pick any wooden or bamboo object near you, such as a school bench, a chair, a stool or a photo frame. Sketch it and label every part. Count the parts. For each meeting place, decide: is it a butt, mitre, lap or mortise-and-tenon joint, or is it held by nails, screws, nuts and bolts, glue or twine? Many school benches, for example, have wooden planks bolted to a metal frame, with no wooden joint at all. Write what material it is made of and how well each joint has lasted. Loose or broken joints are clues about which joints were wrong for the load.

Besides joints, parts are held together with fasteners: nails, screws, and nuts and bolts. Each has its own strengths.

Nails are driven in with a hammer. They are quick and cheap, and fine for boxes and light frames, but they can be pulled out more easily than screws.

• Choose a nail about two and a half to three times as long as the thickness of the piece you are fixing.
• Hold the nail near its head with your fingers, tap gently to start it, then move your fingers away and drive it with firm, straight blows.
• Near the end of a piece, or in hardwood, drill a small pilot hole first to stop splitting.
• To remove a bent nail, slip the claw of the hammer under its head and rock the handle back, with a scrap of wood under the hammer to protect the surface.

Screws have a spiral thread that grips the wood, so they hold much better than nails and can be removed for repairs. Make a small dent or pilot hole where the screw goes, then turn it in with a screwdriver that fits the slot exactly, pressing firmly so it does not slip and damage the head.

Nuts and bolts pass right through a drilled hole and are tightened from both sides. They are very strong and easy to undo, so they suit things that carry loads or must be taken apart, such as bench planks on metal frames or bed frames. A washer under the nut spreads the pressure and stops it digging into the wood.

Joining moving parts: hinges. Doors, windows, cupboard doors, box lids and chests need parts that swing. A hinge joins them while letting them open and close smoothly, and it spreads the strain so the wood does not wear out. Common types are:

• Butt hinges: two small leaves, used on doors and cupboards.
• Piano (continuous) hinges: a long strip, for box lids and folding tables.
• T-hinges and strap hinges: long arms for gates and heavy chests.
• Concealed hinges: hidden inside modern kitchen cupboards.

Fit a hinge so its pin lies exactly along the line of the opening, mark the screw holes through the hinge with a pencil, drill small pilot holes and then screw it in. A hinge fitted slightly out of line makes a door stick or sag.

Before cutting good wood, test your idea cheaply. A prototype is the first model of a product, made to check the design. You make it from cardboard or waste softwood, so mistakes cost almost nothing.

Choosing what to make. Start simple and useful: a coaster, a pen stand, a mobile phone stand, a key holder, a nameplate for your desk or door, a small box, a chalk duster or a bird house. Look at similar objects at home or in shops to get an idea of size and parts.

Steps

• Sketch in 3D on paper. Draw the object as it looks from an angle, then draw each part separately. Write the length, width and thickness of every part in millimetres or centimetres.
• Collect material: cardboard or scrap softwood, a cutter, a pencil and a steel ruler.
• Mark out every part on the material from your sketch. Fit the parts close together to waste as little as possible.
• Cut carefully along the lines, on a cutting board, with the cutter moving away from your hand.
• Assemble with glue or cellophane tape instead of nails. A simple hinge can be made by pushing a bit of old wire through two pieces of cardboard.
• Compare the model with your sketch. Does it stand? Does a phone fit in the stand? Is the angle right?

Why prototype?

• You find out whether a design that looks good on paper can really be built in three dimensions.
• You catch measuring and fitting errors before they waste wood.
• You can change the design cheaply and quickly, as many times as you need.

Review honestly. Were your measurements and cuts accurate? If not, what will you change: a sharper pencil line, measuring twice, a steel ruler instead of a plastic one? How did you join the parts, and was it difficult? Did the model match your sketch? Show it to classmates and note their suggestions. Professional designers, from furniture makers to car companies, make many prototypes before the final product, because a change on cardboard is far cheaper than a change in the factory.

Now make your product in wood. A coaster, a small flat piece placed under a cup to protect a table from heat and water, is a good first project, because it uses every basic skill. You may instead make a nameplate, key holder, phone stand or small toy, following your prototype.

1. Plan. Take your checked sketch and collect material (softwood, plywood or scrap) and tools.

2. Measure and mark. Use a measuring tape or steel ruler and a sharp pencil. Mark square lines with the tri-square. Follow the carpenter's rule: measure twice, cut once. Mark which side of the line is waste.

3. Cut. Clamp the wood firmly in the bench vice with the line just outside the jaws. Start the cut on the waste side with a few short, gentle back strokes to make a groove, then saw with long, steady strokes, letting the saw do the work. Check the cut stays on the line and correct early. Support the offcut near the end so it does not tear off.

4. Plane. A plane shaves thin strips to remove high spots and rough edges and make the surface flat. Plane with the grain, pressing on the front at the start of the stroke and on the back at the end.

5. Drill any holes needed for screws, hanging or decoration, holding the drill at right angles to the surface with the work clamped over scrap wood.

6. Sand. Wrap sandpaper round a small block and rub along the grain. Start with coarse paper (for example 80 or 100 grit), then move to fine (180 or 220) for a smooth finish. Round off sharp corners slightly. Wipe off the dust.

7. Assemble parts as per the sketch, using press-fit joints, glue, nails or screws. Check corners with the tri-square before the glue sets.

8. Finish. Varnish is a solution of resins, oil and a solvent. Brushed on in thin coats, it dries to a hard, protective, scratch-resistant layer that also brings out the grain. Apply a thin coat in an airy place, let it dry fully, rub lightly with fine sandpaper and apply a second coat. You can paint or decorate the product instead.

Judge your work: are edges straight and corners square, is the surface smooth to the touch with no splinters, does it do its job? Write down the process, the tools used, the difficulties and how you solved them.

Bamboo is strong, light, flexible, eco-friendly and easy to find in much of India. Bamboo workers in the north-east, Kerala, Odisha and elsewhere make baskets, mats, furniture, lamps, flutes, toys and even houses from it.

Parts of the bamboo plant

• Rhizome: the underground stem from which new shoots grow, with roots below.
• Shoot: the tender young stem that pushes out of the ground and grows very fast.
• Culm: the tall, woody stem. It is a hollow cylinder that tapers towards the top. This is the part used to make products.
• Nodes: the solid rings that divide the culm into sections; they make bamboo strong.
• Internodes: the hollow sections between nodes.
• Sheath: a leaf-like covering that protects the young, developing culm.
• Leaves grow from branches at the nodes.

Smooth culms are used for handicrafts and utensils, while thick, mature culms are used for poles and furniture. Mature, well-dried bamboo is stronger and less likely to be eaten by insects. Craftsmen often treat it, for example by soaking, to protect it from borers.

Making a bamboo product such as a pen stand, a cup, a planter, a lamp or a small shelf:

• Sketch and plan with width, height and thickness labelled.
• Measure and mark with a tape and marker.
• Cut the culm with a fine-toothed saw or hacksaw while it is held in a bench vice. Bamboo splits easily, so wrap tape round the cutting line and saw slowly. Cutting just below a node gives a closed bottom, ideal for a pen stand or cup.
• Smooth by scraping off the outer skin if needed and removing sharp fibres at the cut ends.
• Assemble parts using drilled holes with screws, nuts and bolts, pegs, glue or lashing with twine.
• Sand edges and surfaces until no fibres catch on your fingers.
• Varnish or paint to protect the surface and make it attractive.

Safety: split bamboo edges are razor-sharp and fine slivers can enter the skin, so wear gloves when handling cut pieces and sand every edge.

Record which object you made, its sketch with dimensions, the process and tools used, the difficulties and what you did to make it attractive.

Costing. To decide a fair selling price, first find what the product cost to make. List every material with quantity, cost per item and total cost: wood or bamboo, nails or screws, glue, sandpaper, varnish or paint, and anything else. If the school bought or rented tools, include a small share of their cost. Then think about your labour: note the hours you spent and give them a value, for example the local hourly wage for a helper.

Selling price = total cost + profit. Compare with similar products in a local shop or online. If the market price is lower than your cost, ask why: perhaps factories make them faster, use cheaper material or make many at once.

Basic repairs. Wooden objects need maintenance, or their life is shortened. Typical jobs are tightening loose screws and nuts, re-nailing or re-gluing a loose part, sanding rough or splintered edges and repainting or re-varnishing worn surfaces. Use your skills on school benches, desks and cupboards, with your teacher's permission. For each repair record: the task, whether it was fixed and how, whether it now feels strong, and any further improvement needed. For example: a wobbly bench top was fixed by tightening its screws; it now feels strong, but its edges still need sanding.

Going further: make music. Simple instruments are a wonderful next project: an ektara, the one-stringed instrument found across India, from a bamboo neck and a coconut shell or hollow gourd; a bamboo flute with holes drilled along a hollow section; a damaru from two small bowls joined at the centre; a shaker of seeds in a sealed bamboo tube; clappers from two flat wooden pieces; or chipli and ghungroo bells fixed to wood. A class can form a mini orchestra. You can also reuse old wood, turning a broken drawer into a shelf or scraps into gifts.

Reflect: log the periods spent on each activity, what you enjoyed, what you would change and three things learnt from the carpenter. Look for wood in literature and scriptures, too.

Careers linked to this work include carpenter, furniture designer, interior designer, bamboo craftsperson, wood technologist, boat builder, musical instrument maker and forest officer.