Today, let everyone get to know the most basic and important aspect of the
leather goods industry. Section: Paper pattern making (if you are a master, please ignore it). Whether it is industrial mass production or personal
handmade production quality, paper pattern making is a must , it depends on whether the paper pattern is made by hand or by a computer CAD system. Before officially starting the tutorial, let me show you some photos:
This is a backpack I made that I have shown you before. Among purely handmade leather goods, relatively few people make backpacks like this. The structure and craftsmanship are very complicated, and for some people Even for people who have some experience in making leather goods, it will be difficult because there are many things involved. However, I want to tell you that although it is complicated, it also starts from the most basic paper pattern making, but the shape of the paper pattern is not so regular. The basic principles are the same, so as long as you start from the most basic paper pattern making, Slowly digest, practice, understand, and summarize, you can do anything more difficult than this. Do not believe? Follow me and read down patiently:
These are the most basic tools for paper pattern making, from left to right: 24-inch steel ruler, 12-inch steel ruler, compass, pen (it is best to prepare an extra pencil), knives, and awls , diamond chopper (optional, but it is best to have stitched handmade leather goods patterns), punch (optional, choose according to process needs), yellow soft ruler, cardboard (upper right corner, preferably 250g or 350g single-sided white card), and of course green plastic board (required for both paper pattern making and leather cutting). The following two pictures show the basic skills of using a knife:
Whenever the vertical surface of the knife must be perpendicular to the plastic board, this is true for pattern making and material cutting. This is particularly important and should be paid special attention to. Otherwise, the pattern you make will not be standard. The opening of the cut leather must be diagonal.
Cut straight lines or When bending edges with a large arc, it is best to control the angle of the knife edge at 35 to 45 degrees, so that the cut edges are smooth and burr-free; for curved edges or round holes with small arcs, it is necessary to gradually increase the angle of the knife edge. Corners, sometimes even need to be vertical.
Let’s do it first Make a large paper pattern for a wallet. First, cut a piece of white cardboard that is larger than the size of the wallet (2-3cm larger on each side) and set aside.
The picture above is Find the lengthwise center of the piece of cardboard and mark it with the tip of a knife. (First add some common sense: Any engineering drawing or structural drawing must be made without coordinates. The same is true for paper pattern making. If we want to determine the shape of the cutting piece, we must first establish a cross coordinate for it, which is the cross-vertical X-axis and Y-axis. axis, and then determine the edge and cutting edge of the piece in the four quadrants separated by the two axesThe location of each component inside the chip. This may sound a bit lofty, but it actually means having a position reference line. )
Steel ruler The edge of the paper is close to the midpoint, and use a knife to gently scratch the surface of the cardboard. (Never use force to scratch through the cardboard.) As shown in the picture above
Then fold it inward along the drawn center line to get the longitudinal Y axis. As shown above
Fold in half Finally, use the same method as above to find the midpoint of the X-axis. Use the tip of the knife to poke through the two layers of cardboard.
Open the folded Cardboard, you can see that the two points that you click through when folding are symmetrical to the Y-axis. Use a steel ruler to connect the two points, and the edges are aligned with the two points. As shown above
Similarly Use a knife to gently scratch the surface of the cardboard along the edge of the steel ruler. As shown above
After breaking the epidermis, the transverse X-axis is obtained. Fold inward along this line. As shown in the picture above, theoretically the X-axis and Y-axis should be absolutely vertical at this time, but it may not be the case when actually making paper patterns.Deviation occurs. We use the following method to check whether the cross coordinates we made are perpendicular to each other. First, fold the cardboard with the cross coordinates just made in half along the Y-axis. At the X-axis near the edge of the cardboard, pierce the two layers of cardboard vertically with the tip of the knife facing the X-axis. As shown below
Knife Don't remove the tip first, turn the jammed paper over to see if the tip of the knife is on the line of the X-axis on the other side. As shown in the picture below, it is just on the line, which means that when we make the cross coordinates, they are perpendicular to each other. Otherwise, they are not vertical and the cross coordinates need to be made again. As shown below
Cross The coordinates are vertical and correct, and we can proceed to the next step. Determine the length and width of the cut piece. First, measure half of the widest dimension of the cut piece vertically outward along the X-axis, and pierce the cardboard vertically with the tip of the knife at half of it. (You can also determine the longest side size first) (as shown below)
Then fold the cardboard in half along the Y axis, find the piercing point in the picture above, and use the tip of the knife to vertically pierce the folded cardboard on the other side (that is, symmetry this point to the Y The other side of the axis has gone. (As shown below)
Open the cardboard, then fold the cardboard inward along the "text-align: center;">
Along the steel ruler, the tip of the knife Vertically, use appropriate force to remove the jammed paper on the outside of the steel ruler.By cutting out, the widest dimension of the piece is determined. (Note that the fingers must be pressed on the inside of the steel ruler to prevent the knife edge from hurting the hand. The force is appropriate, as long as the steel ruler does not move.) As shown below:
Use the same method to determine the longest size of the cut piece. Measure half of the longest side of the piece vertically outward along the Y-axis, and pierce the cardboard there with the tip of the knife. (As shown below)
Fold the cardboard inward along the That is to say, this point is symmetrical to the other side of the X-axis. (As shown below)
Open the cardboard, then fold the cardboard inward along the Y-axis, use a steel ruler to connect the two punctured points in the picture above to the edges, and cut off the cardboard outside the steel ruler. (As shown below)
In this way we determine the longest and widest piece. Get the following rectangular piece.
At this time The corners of the cut pieces are all right angles. If you want rounded corners, you have to cut off the right corners. Let’s first get to know a self-made tool. Corner filler (set of arcs with different radii, from radius 1mm to radius 25mm)
Usage is as shown below: Align the two straight edges of the rounder with the two straight edges of any corner of the cutting paper.
Use the tip of the knife along the circle Use the arc edge of the corner cutter to cut off the corners of the cardboard. (As shown below)
Round the corners, and then use this corner as a template to cut off the other three corners.
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After repairing the four corners, the following picture is shown:
Next, we use diamond chop to determine the suture position. First , determine the margin of the suture, and use a compass to measure the margin of one minute (metric unit is about 2.6mm). As shown below
Use a compass with adjusted margins to mark the edges on the cutting pattern: as shown below
After marking the edges, first use six holes Ling Zhan hits from the midpoint of any side to both sides.Kong, the first chop of Ling Zhan is aligned with the midpoint: as shown below
After making the first cut, the first hole of the second cut coincides with the last hole of the first cut, so as to avoid inconsistent stitch length and line bending as much as possible. As shown below:
When making the last cut, use the diamond cutter to get close to it and see if there is a half-stitch phenomenon at the end. If there is a half-stitch phenomenon, either fine-tune the stitch length in advance or trim the edge length of the pattern appropriately. As shown below
Half side After drilling the holes, fold the paper pattern in half along the axis and copy the hole locations to the other side. As shown below
Use the above method to punch holes on the remaining edges that require stitching, and finally get the following pattern:
In order to prevent confusion in management when there are too many paper patterns, we code a style number and cut name for each pattern: as shown below
Finally, you can use it to cut leather. .
For more cutting pieces, use the above method Just make them one by one.
Paper pattern
