The purpose of making the canvas is to block the pores, smooth the texture, block the penetration of linseed oil, add white paint to make the canvas more difficult to absorb and brighter; increase it to be denser and thicker, so that the artist can better achieve its purpose. And make the work durable, and play the function of adhesion, support and protection to the work.
The purpose of the foundation
oil painting uses dry vegetable oil such as linseed oil to form a film to fix the paint. Linseed oil will penetrate on the cloth, wall, wood block, and other reasons. To create oil paintings on this kind of material, a layer must be made to prevent the penetration of linseed oil.
Canvas production is to solve the following problems of the linseed canvas base fabric through the foundation:
1: Blocking the pores and grains of the grain to solve the flatness problem of the canvas;
2: Blocking oil absorption and oil penetration to solve the absorption problem of the canvas;
3: Forming a compact, thick, strong and dimensionally stable base to solve the durability problem of the canvas;
4: Cover the base fabric color and add white paint to solve the problem of bright canvas.
1: The fixing of the canvas should be straightened and tightened, and the surroundings should be fixed on the board or frame with dense nails; you can first brush the cloth around with glue, and then it will harden to reduce the bending deformation; 2: The scraping of the primer Do not mix the primer with water or a very small amount of water. Use multiple thin scraping methods, and each layer should be thinned evenly. Seal the pores of the texture, and there is no bright light point under the light. Sometimes burrs are produced and need to be repaired and polished. The force should be light, fast, fast and uniform. If the local force is too large or the squeegee is uneven, or if too much water is added, it will penetrate to the back and form thick and hard spots. After the glue dries, it will foam and bulge. Fix tightly. 3: The painting canvas of the base material is stable and flat after the base is blocked, the base material can be brushed, and the base material can be brushed evenly several times, and it is white and bright. 4: The thickness and smoothness of the base, the thickness of the handle is controlled by the amount of scraping glue, and the bottom surface is smoothed by sanding. The painter likes the smooth and not greasy dry feeling of egg crust. 5: Absorbency control The professional canvas factory has different absorbent base materials. The self-made base material itself absorbs oil, so I had to add an appropriate amount of linseed oil to the base material to control the absorption. The so-called oily, semi-oily foundation. After thorough drying, it can block the further penetration of linseed oil. But take time to wait for the foundation to dry naturally. 6: Durability Choose durable primer, and the primer should contain enough glue. The paint layer must be adhered to a strong enough substrate to be preserved for a longer time.
Oil canvas must be equipped with frame strips, and add cross braces, and use the tenon and tenon structure to make the frame. Prevent the picture frame from curling, beveling, curved and shaking. The cloth nails should be evenly and tightly distributed. If the frame surface is deformed due to shrinkage after the coating is dried, heavy nails need to be adjusted to make the frame surface flat and tight. Before cutting the cloth, measure the size and make a mark, and use a sharp pen to draw a line along the cloth pattern at the mark, and then brush a few centimeters of primer at the mark, and cut it after drying. This will ensure the squareness of the canvas and no yarn loss. It is also good to stretch the edges of the frame surface to prevent the cloth pattern from bending and causing the foundation to crack and fall off in the future.
Pine: Hard and heavy, dense wood grain, bright yellow in color. Not easy to deform, high-quality frame.
Paulownia: fast-growing wood, hard cartilage, lighter, gray color and sparse wood grain. Not easy to deform, suitable for commonly used frames.
Shanmu: Hard, brittle, cracked, bright yellow wood, clear grain, many knots, not easy to deform, suitable for commonly used frames.
stretch frame method
Professional canvases, whether back or side nails, have a regular pattern to make the canvas "flat and straight". The manual nail frame can only be tightened one by one, and then nailed. Then the nail position and order are very particular.
The first step: First, nail the canvas in the middle of a frame (such as the one on the left). Then nail the canvas tightly in the middle of the opposite frame (the one on the right). Then nail the canvas in the middle of the lower border strip, and nail the canvas tightly in the middle of the upper border strip. The oil canvas forms a fixed "cross" on the frame.
Step 2: Stretch a corner of the canvas along the diagonal of the frame (such as the upper left corner), select the end of the left or upper frame to temporarily nail the canvas. Fix the four corners of the canvas in this way. The oil canvas is fixed in the shape of "m" on the frame.
Step 3: In the middle of a frame (the canvas has been nailed in the middle), nail the oil painting plazi once (for example, one on the left) with a distance of 2-4 cm on both sides. Then nail the canvas tightly on both sides of the opposite frame (the one on the right) with a distance of 2-4 cm. Then nail the oil canvas at the middle position of the lower border strip 2-4 cm apart on both sides, and nail the oil canvas tightly at the middle position of the upper border strip 2-4 cm apart on both sides. In this way, the four frame strips gradually advance from the middle to the ends to fix the canvas.
The fourth step: Finally, fold the four corners of the canvas back and nail it. (When it is fast to fix to the four corners, the nails that temporarily fix the four corners of the canvas in the second step may be in the wrong position and must be lifted and adjusted)