Such an ordinary and useful thing as a sketching pencils does not raise any questions – everything is clear and understandable, take it and draw. Nevertheless, it is quite difficult to call a pencil a simple object, because it will take at least 11 days to produce it. At the same time, over 80 operations involved in the production cycle and more than 100 types of raw materials used.
Production technology
The current technological processes are almost the same as those that existed a hundred years ago.
Preliminary manipulations
Smooth, with a minimum number of knots, linden, aspen, cedar logs are first soaked in water, after which a bar is cut out of them. Each workpiece divided into several workpieces and calibrated into identical plates with perpendicular edges. Under the influence of high pressure and steam, resins squeezed out of the boards, and the wood itself is impregnated with paraffin. This measure will give future pencils strength and stability in the fight against the harmful effects of the environment.
Only the boards that are well dried after this procedure can be used in the production of sketching pencils.
Workshop “white pencil”
This is the name of the shop of unpainted pencils. Here, hollows for the rods made in already polished boards. With the help of a special machine, the core falls into the grooves, the filled board is covered and glued to the second one. After that, it is necessary to re-dry in a special chamber at a temperature of 35-45 ° C for 2-4 hours – depending on the fat content of the lead.
The next step is to separate the wood blocks with rods into separate sketching pencils. This work performed by a machine, a double cutter of which bends and saws them in such a way that the output is a ready-made pencil without any paintwork. Depending on the shape of the cutter, graphite pencils become either round or flat, triple or hexagonal.
The finished product undergoes visual inspection, in which defective items selected manually. Defects include chips, traces of wood burns, scratches, roughness, etc. A selected high-quality product or sketching pencils sent for painting.
Dyeing shop
As paints, a powdery chemical composition used, diluted to the desired consistency. Pencils colored automatically: during the passage along the conveyor belt, the coating layer has time to dry. In total, five layers are applied: three layers of paint and two layers of varnish, so the procedure is repeated several times.
Shop for the production of slates
Pencils made from a mixture of graphite and clay, ground into powder and moistened with water. The conglomerate cleaned of impurities and sent under the press. Subsequently, the mass squeezed out through the thin holes of the stamping machine.
The resulting fragile workpieces placed in a special container and sent for drying, after which they undergo a thorough inspection and rejection. Ideal samples fired at a temperature of 800-1200 ° C: it is the selected temperature regime that affects the softness of the pencils. The accepted scale of the structure of pencils ranges from 17 options (from 7H to 8B).
Home stretch
The final look of the pencils given by a thermostatic stamp with a gold or silver coating, an eraser attachment and sharpening with a rotating abrasive disc. The latter operation performed at very high speed and takes literally moments.
Most black lead pencils sold individually, less often in sets of units of varying degrees of hardness. Ready-made sets of colored pencils contain 6, 12, 24, 48 and more pieces per pack.
Ease of use. A schoolbag or backpack for school must have a sufficient number of compartments and pockets (both internal and external). Zippers and fasteners should be easy to open and close. Just because of it that student can quickly get the thing he needs. Also pay attention to the material of the knapsack itself. It is better to give preference to materials that are not whimsical in washing and caring for it.
The bottom of the satchel must be waterproof. As you know, a schoolchild can put a backpack in the snow. For models that have a waterproof bottom. Such contamination is not terrible, and all textbooks and notebooks will remain dry and unharmed.
Appearance. For both a primary school student and a high school student. A schoolbag is not only a bag for carrying textbooks, but also a kind of accessory. When choosing a satchel or backpack for children. Do not forget to take into account the opinion of your child. Nowadays you will find a huge assortment of backpacks and satchels, all kinds of colors. Cartoon characters, cars, butterflies, animals, princesses. This is not a complete list of images on backpacks that you will meet when you are going to buy a school backpack. Do not forget to take into account the opinion of your child. Nowadays you will find a huge assortment of backpacks and satchels, all kinds of colors.