Open it up. OptiNest - creating a cutting map for curved parts The best program for cutting sheet materials
Cutting – a program for cutting sheet materials: particle board, glass, etc. The program for cutting chipboard allows you to reduce and optimize material consumption; it records waste, including “business” waste, which is not taken into account when calculating the cost of the order. The utility can be used in enterprises engaged in the mass production of cabinet furniture; for this purpose, the concept of ordering has been introduced into its functionality. All completed orders are automatically entered into the order database, and subsequently it is possible to repeat or change them. You can download Opening for free on this website.
To start working with the utility, you need to set the dimensions of the sheet and the parts that will be cut from it. Next, the program will independently select best option cutting with the least amount of waste. If necessary, you can use the material database available in the program, which contains standard sizes of sheets or rolls. In this case, it is enough to specify the material to be cut, and the utility will automatically calculate according to the standard parameters of the sheet.
The cutting program works according to two main algorithms for optimizing chipboard consumption - reducing total waste and increasing continuous cutting. Reducing overall waste means cutting with a minimum amount of scraps. The continuous trim increase mode, in addition to reducing waste, is used to create a maximum trim that can then be used for another order. You can also save on material by combining two orders if they use the same material.
The main advantages of the Cutting utility
- Two cutting optimization algorithms.
- Database standard sizes sheets.
- Working with two types of edges.
- Works with both sheets and rolls.
- Database of completed orders.
During cutting, all cuts are made from one edge of the sheet to the other - either horizontally or vertically. The material consumed for cutting and other technological operations is taken into account when calculating cutting. The utility allows you to work with two types of edges. The program allows you to optimize the consumption of not only sheets, but also rolls. If necessary, it is possible to use Cutting in online mode.
Economical linear cutting of materials (cutting moldings) is relevant for many industries and in construction. This is cutting logs and boards in woodworking, cutting rods, reinforcing bars, angles, channels, pipes, I-beams into blanks...
In the production of metal structures and mechanical engineering, cross cutting of rolls of paper and fabric in the pulp and light industries.
Despite its apparent simplicity, solving linear cutting problems is not an easy task, but a worthwhile one. The introduction of a scientific approach to cutting molded materials can sometimes reduce costs by more than 10%! Read the article to the end and make sure these words are correct.
The topic under consideration relates to linear programming problems. To solve such problems, scientists have come up with several different methods over the past 70 years.
Index method L.V. Kantorovich and V.A. Zalgallera with a certain skill allows you to “manually” without using computer technology Effectively perform linear cutting. I recommend that curious readers familiarize themselves with this method by reading the book by the above-mentioned authors, “Rational Cutting of Industrial Materials.”
Simplex method based on the ideas of L.V. Kantorovich, was described and developed in detail by a number of scientists from the USA in the mid-20th century. The MS Excel add-in “Solver” uses this algorithm. It is with this method thatExcelIn this article we will solve the problem of linear cutting.
Later, genetic, greedy and ant algorithms appeared and were developed. However, we will limit ourselves to listing them and get down to business without getting into the jungle of theories (although there, “in the wilds,” it is very interesting).
Let's turn on Excel and simple example cutting metal rods into parts, let's get acquainted with one of the solutions practical problems linear cutting. Mathematicians often call this problem the “cutting problem.”
I did not invent the initial data for the example, but took it from M.A. Pokrovsky’s article. “Minimization of inevitable losses of materials in industrial production when cutting them into piece blanks” published in No. 5 (May 2015) of the electronic scientific and technical journal “Engineering Bulletin” published by the Federal State Budgetary Educational Institution of Higher Professional Education “MSTU named after. N.E. Bauman" (link:engbul. bmstu. ru/ doc/775784. html).
The goal I pursued was to compare the results obtained from solving the problem.
An example of solving a linear cutting problem in MS Excel.
Let's agree that:
1. Blanks are the starting material in the form of rods, strips, rods, etc. the same length.
2. Parts are elements that must be obtained by cutting the original workpieces into pieces.
3. The width of the saw, cut, and cut is assumed to be zero.
The task:
To complete one of the orders, the procurement area must be cut into combined scissors from identical billet rods 1500 mm long, three standard sizes of parts:
151 pieces 330 mm long
206 pieces 270 mm long
163 pieces 190 mm long
It is necessary to find the optimal cutting plan that uses a minimum amount of material and, accordingly, produces a minimum amount of waste.
Initial data:
1. Length of the original blanks Lh in millimeters we write in the combined cell
D3E3F3: 1500
2. Assigning numbers i all standard sizes of parts, starting from the longest to the shortest in the cells
D4; E4; F4: 1; 2; 3
3. Part lengths Ldi in millimeters we write in
D5; E5; F5: 330; 270; 190
4. Number of details Ndi in pieces we enter in
D6; E6; F6: 151; 206; 163
5. Let's get down to very important stage– filling out cutting options.
Must be remembered and understood 2 principles for doing this work.
1. Waste lengths must be less than the smallest part ( 0< Lo j < Ldmin ).
2. We begin “stacking” parts into a workpiece with the largest parts and the largest number of them, consistently moving towards reduction.
If there is no standard size of parts in the cutting option, then we leave the cell empty, we will not write a zero to facilitate the visual perception of the table.
Cutting option No. 1:
Trying to cut 5 parts No. 1 from one blank is impossible, so we write in the cell
It is also impossible to add part No. 2 or part No. 3 to the cutting, so we leave the cells empty
Cutting option No. 2:
We reduce the number of parts No. 1 by 1 from the previous option and write it in
We try to add 2 parts No. 2 - it doesn’t work, so we add in
It remains possible to supplement the cutting with part No. 3. We put it in
Adhering to the stated principles, we fill in by analogy all 18 possible cutting options in this case.
Having made a couple of tables of cutting options yourself, you will understand the logic of the actions and will spend a few minutes on this work.
If the first principle is not followed during cutting, then the cell with the waste length is automatically painted red. Conditional formatting applied to cells G7...G24 will clearly help you in this work.
We don’t write anything in cells H7…H24! They are used to display the result of the solution!
Preparing for the solution:
* In cells G7...G24, the lengths of waste (cuts) remaining as a result of cutting are calculated using the formula
Lo j = L z —Σ (Ldi * Ndij )
6. The number of parts of each standard size, manufactured using all applied cutting options, will be calculated in cells D26, E26 and F26 using the formula
Ndicalculation = Σ (Ndij * Nhj )
The number of parts in the cutting plan found at the end of the solution must fully correspond to the specified number of parts!
7. The required number of workpieces to complete the optimal cutting plan will be determined in the combined cell D27E27F27 using the formula
N z calc =ΣN hj
8. The total length of all blanks required to perform linear cutting of all parts will be calculated in the combined cell D28E28F28 using the formula
Lh Σ = L z*Nz calc.
9. The total length of all waste obtained when executing the found cutting plan will be calculated in the combined cell D29E29F29 according to the formula
LO Σ = Σ (LOj * Nhj )
10. The share of waste obtained when executing the optimal linear cutting plan from the total amount of material used will be calculated in the combined cell D30E30F30 using the formula
Ωo = Lo Σ /Lз Σ
Solution:
The preparation is completed, 18 options for the most optimal cutting of one workpiece into parts have been identified and all the necessary formulas have been entered. Now the main task remains to be solved: to determine optimal cutting plan - how many blanks, and what cutting options to cut to eventually get everything necessary details in the right quantity with a minimum of waste.
1. In the main menu, select “Service” - “Search for a solution...”.
2. In the “Search for a solution” window of the same name that appears, we make the settings.
2.1. Assign the target function to the total length of waste Lo Σ and enter the link into the target cell window.
2.2. Set the “Equal:” switch to the “minimum value” position.
2.3. Specifying cells with variables Nз j in the Modifying Cells window.
2.4. We enter restrictions in the window of the same name. As conditions we indicate the need for equality of the given Nд i and calculated Nd icalc number of parts, as well as variables Nз j– the estimated number of blanks according to cutting options – we impose a limitation: these must be integers.
3. Click the “Options” button and in the “Solution Search Options” window that pops up, make the settings as shown in the following screenshot. Close the window with the “OK” button.
4. In the “Search for a solution” window, click the “Run” button and wait for Excel to find a solution. This may take several minutes.
5. After saving the found solution with the “OK” button, the results will be displayed in cells H7...H24 on the Excel sheet.
The following picture shows the found optimal linear cutting plan.
What's the result?
Linear cutting in Excel of blanks for tasks similar to those discussed in this article is performed using the method described above in 10-15 minutes! “Manually”, without knowing the method of Kantorovich indices, you will not find a solution in such a time.
Having launched “Search for a solution” several times with different search parameters, we were able to find 5 different cutting plans. All 5 plans require the same number of blanks - 93 and produce waste of only 2.21%!!! These plans are almost 6% better than the plan calculated by Pokrovsky and more than 10% more economical than the “Traditional” plan (see the link to the source in the first part of the article). A very worthy result was achieved quickly and without the use of expensive programs.
It should be noted that the Excel Solver add-in (“Search for a solution”), which uses the simplex method when solving linear programming problems, can work with no more than 200 variables. When applied to the linear cutting problem we considered, this means that the number of cuttings cannot exceed 200 options. For simple tasks It's enough. For more complex problems, you should try using a “mixture” of the “greedy” algorithm and the simplex Solver method, selecting from full list cuttings no more than 200 of the most economical. Next, we stock up on patience and achieve results. You can try to break a complex problem into several simple ones, but the “level of optimality” of the solution found will most likely be lower.
Perhaps the considered option for solving linear cutting issues is not “aerobatics,” but it is definitely a step forward compared to the “traditional” approach in many industries.
The use of the MS Excel add-in “Search for a solution” (Solver) has already been discussed once on the blog in an article. I think that this wonderful tool is worthy of close attention and will again and again help you elegantly and quickly solve a number of new non-trivial problems.
P.S. Links to the best free linear cutting programs I found on the Internet:
http://stroymaterial-buy.ru/raschet/70-raskroy-lineynih-izdeliy.html
http://forum-okna.ru/index.php?app=core&module=attach§ion=attach &attach_id=7508
http://forum.dwg.ru/attachment.php?attachmentid=114501&d=13823277 74
http://www.planetcalc.ru/917/
The programs in the last two links implement greedy heuristics and perform linear cutting in the problem from the article, using as many as 103 workpieces. The use of greedy algorithms is justified in cases where it is necessary to reduce the total time of the cutting operation when there are too many cutting options in more optimal plans.
Below the article in the “Reviews” block, you can write your comments, dear readers.
Sirius is cutting program sheet metal and NC code generation
The program for cutting sheet metal "Sirius" is a highly efficient CAD/CAM that combines the formation of a sheet cutting map for arbitrary workpieces with the generation of optimal control programs for CNC machines. Shaped or rectangular cutting of sheet metal is supported. Operating mode - auto And interactive. The main advantage of using the program is to increase metal utilization factor(CMM) and creation of control programs that ensure the minimum stroke of the cutting tool.
Advantages of the Sirius system
- A powerful specialized graphic editor that provides interactive design of a cutting card with the highest possible metal utilization rate in minimal time.
- Sirius turns on figured cutting And rectangular cutting sheet metal with maximum utilization rate
- Accounting technological features thermal cutting and the capabilities of CNC equipment in the process of generating programs for CNC machines that cut sheet metal
- Interface with other CAD/CAM/CAE/PDM systems via standard data exchange files, import-export of geometry in DXF format
- Postprocessors for generating programs for CNC machines with support for all types of domestic and foreign technological equipment for cutting sheet metal metal. If the required CNC post-processor is not available, then it is developed (see price list)
- Simulator (inverse postprocessor) for verification and editing of control programs for CNC machines
- Optimization of cutting costs on CNC machines, minimization of thermal deformation during thermal cutting
Cutting diagram obtained using the NCL algorithm
KIM = 80%
The NCL algorithm allows you to cut a sheet of any shape (see figure on the right).
Now, along with the NCL algorithm, an additional algorithm from Algomate can be supplied, which provides very high CMM (see example)
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Interactive and automatic cutting
The interactive mode of designing a control program in the SIRIUS system is as automated as possible. At the same time, the user can flexibly manage options technological process, to decrease metal cutting cost.
In particular, when preparing control programs for laser, water-abrasive, plasma-cutting and gas-cutting machines, the subsystem provides the ability to set effective technologies thermal cutting such as “combined cut”, cutting with jumpers, cutting groups of parts without turning off the cutter, cutting with multiple supports, etc. The technique of subroutines is supported. All of the above allows you to select the most effective mode that reduces metal cutting cost.
Machines for straight and curved chipboard cutting
Our company “site” produces machines for straight and curved cutting of chipboards in various configurations in agreement with the customer.
CNC milling machines from our company perform straight and curved cutting of chipboards with two types of tools.
1. Cylindrical end mills with a diameter of 10 to 25 millimeters are used for curved and straight cutting of chipboard.
2. Disc cutters on a special corner attachment perform straight-line cutting of chipboard, which is faster and more productive.
Straight cutting Disc cutters were previously performed only on format cutting machines. Modern three-axis CNC milling machines replace a whole line of old machines and create new opportunities to improve product quality, save material and significantly increase labor productivity. An optional disk cutter on an angular drive allows for straight-line cutting at high speed. Replaceable modular cutters allow you to perform cutting, figured bas-relief carving, inserting stained glass windows, and reducing human errors from one sheet installation.
Available software portal milling machines gives a powerful impetus to the use of new technologies. Computer placement of parts on the cutting sheet allows rational use of the sheet area. The efficiency of using our machines is especially high when making shaped blanks for curved contours: computer radius tabletops, armchairs, stair railings, arched body kits, furniture facades. Making rectangular blanks for curved contours using classical machines leads to significant losses of quality material due to scraps.
In addition, it is necessary to use up to three different machines for machining one furniture part.
1. Format cutting machine for producing rectangular blanks.
2. Band saw for cutting the curved contour of the part.
3. Milling machine for cutting out relief decorative design of the plane and edge.
4. Drilling machine for installation of accessories.
On our milling machines, curved cutting and relief processing operations are performed from one installation on one machine with several changes of working tools.
Even if there is a decorative relief, all milling operations of complete processing are performed on just one machine in one installation. The painstaking operations of calculating the cutting sheet for workpieces, marking and adjusting milling grooves, tenons, adjusting the sketch scale, calculating the location of the relief thread are performed on the computer screen instantly and with high accuracy. Using a special software application of the machine, the loaded graphic drawing of the drawing quickly turns into a program for processing the surface of the door with all the idle and working movements of the cutters and tool replacement.
The full cycle of all milling operations, cutting and finishing is performed by a CNC three-axis milling machine with the additional option of spindle rotation by ±90 degrees; spindle rotation is performed either programmatically or manually as an additional option. With program control of spindle rotation, the machine becomes four-axis. The processing tool can be changed manually or optionally via software.
The machine has fifteen units:
1. Program control panel with keyboard and LCD screen.
2. Welded frame made of square pipes according to the maximum size of a standard factory-delivered MDF or chipboard sheet or the maximum size of customer parts.
3. Two longitudinal guides for the transverse portal.
4. Transverse portal with caliper guides milling spindle.
5. Milling spindle with ±90° rotation function.
6. Two longitudinal guides for traverses.
7. Four pneumatically fixed transverse crossbars with T-shaped longitudinal grooves on the top and sides.
8. Two adjustable pneumatic suction cups on each traverse with pneumatic fixation of the suction cups.
9. Four pneumatically extendable positioners mounted on traverses.
10. As an option, the workpiece laying table can be flat with vacuum channels
11. Air pump with equipment for maintaining stable discharge.
12. Device for chip collection and dust suction.
13. Spindle cooling device with compressed air with a compressor.
14. Stand for fastening interchangeable tools for 10 positions with a special socket for holding the collet when changing the cutter.
15. Special angular drive of the disk cutter.
High quality patterned surface processing is achieved by using an end mill with a tip radius of about 1 millimeter, which in turn requires a large number of tool passes in increments of no more than 1 millimeter. The total processing time is thus increased to 100 or 160 minutes depending on the tool.
Our company’s CNC milling machines compare favorably with competitors:
High productivity, rotation speed of the milling spindle up to 20 thousand revolutions per minute,
Precision drives for processing complex surfaces,
Light and quick replacement programs for patterns and holes for fittings, almost all parts can be exclusive,
Easy and quick installation of workpieces on the machine using four retractable pneumatic positioners,
Instant fixation with vacuum suction cups on movable traverses with pneumatic clamps,
Reducing the risk of human factors in complex processing and design operations,
A huge resource of highly reliable drives, gearboxes, spindles, guides and carriages from well-known manufacturers,
One-year warranty and lifelong support of your machines.
The site company manufactures CNC milling machines for straight and curved cutting of chipboards that meet all agreed customer requirements. Components are purchased directly from the world's best manufacturers in Europe and Asia. During the first start-up of the equipment, customers are trained to operate the machine. The production time depends on the speed of delivery of components and is within three months.
The site company provides warranty and post-warranty service and supply of spare parts. The warranty period for our machines is one year, the warranty for purchased components is in accordance with the attached manufacturer’s passports.
CNC milling machine with a large working field 3700 x 5000 mm
articles and guides on how and what you can do with your own hands. Delivery of goods is carried out throughout Russia. The warranty is provided for and. You can buy or order products at the address: Rostov region, Aksai district, Rassvet village, st. Magistralnaya 7.
Anyone who is more or less familiar with the process of making cabinet furniture probably knows at least one of the programs designed for creating cut cards for sheet materials - chipboard, MDF, fiberboard, plywood, etc. Seven out of ten people, if asked, would name the Cutting program. It is intended precisely for these purposes - it allows you to lay the N number of rectangular parts on the M number of rectangular blanks (from which these N parts can later be cut). I won’t dwell in detail on the review of this program - I think everyone already knows everything. I’ll just say that there are versions of casting 2 and 3. I tried the third one a long time ago and didn’t like it. I don’t even remember why. Version 2 turned out to be more successful.
The main advantage of this program is the ease and simplicity of obtaining a cutting map for rectangular parts. Well, what should you do if you need to tightly place curved parts on a limited piece of material? There are a number of programs that allow you to solve this problem. For example Astra S-Nesting or ProNest
But I won’t tell you about these programs. Eat personal experience communication with OptiNest.
In a nutshell, the difference between this program and Cating. Cutting is intended almost exclusively for the format-cutting machine. This introduces some features into the construction of the cut map. OptiNest is designed for use in CNC machines. Regardless of how exactly the machine cuts the material: laser, water, galvanic or milling cutter. This eliminates the need to be tied to straight cutting lines; it is possible to cut parts of almost any shape, place them straight or reverse, and even one inside another.
As a rule, such programs do not have the ability to create the shape of future parts in their environment. OptiNest, which was a pleasant surprise, has a simple constructor in which you can draw the shape of parts directly in the program. But it is not suitable for our purposes - to create furniture from plywood using CNC, precision cutting is required. Introducing an error even at the moment of drawing the part is an unaffordable luxury - there is no need to use CNC at all. Take a jigsaw and cut it - the result will be the same.
In this regard, almost all curved cutting programs support importing parts from CAD programs. OptiNest is no exception. It supports the ability to import a parts file saved in dxf format.
What will we do next? I will show the process of creating a cutting sheet for curved parts made of plywood measuring 2500 by 1250 mm using the example of a project for a plywood stool model T1. Let's see how many sets of stools can be made from one sheet of plywood.
1. Launch OptiNest. This is what the window of the newly opened program looks like.
2. Create new project – click on the “blank sheet” in the upper left corner. We get:
3. In theory, you would need to set the program settings, but first exporting plywood stool parts. Selecting parts export:
Select the project file in dxf format, we get:
Here you can leave everything unchanged. Just check that the dimension is in millimeters.
At this stage, you can choose which lines need to be transferred to the project and which not.
Click OK. We get the following window
A window for each added detail. You can scroll through them all, entering the necessary parameters for each, or just click OK. Then all the details will be added to the project and only then it will be possible to open the property the required part and change the necessary parameters.
What you need to pay attention to here. By default, in this case, everything suits us. But for the future, you need to understand two main points: the choice of resolution for changing the position of parts on the blank sheet. The part can be allowed to rotate and flip. If the direction of the texture of a part is important to you, you need to prohibit its rotation while calculating the cut map. If you use single-sided laminated plywood as a material, you need to uncheck the Reversal checkbox, otherwise the laminated layer may end up on the wrong side of the part.
Ready. A set of parts for making one plywood stool has been loaded into the program.
4. Let's start setting the dimensions of the workpieces. But before that, let’s add by eye the number of stools that we would like to get from a sheet of plywood. Double clicking on a part opens a window with its parameters - specify the quantity of all parts - 6 pcs. The screenshots below already indicate that we are going to place six parts of each type on a sheet of plywood.
Let's create a blank. Go to the Stock menu and select Panels Stock
A window opens
This is a library of blanks - sheets of material on which we will place the stool parts. I have already created a blank for myself called Plywood 2500*1250. I'll show you how to create a new one.
Click the New Stock button and the line we call appears. Let's just say plywood. Double click on this line (or use the Edit button)
The name has been created, but it does not have any parameters yet. Press the NEW button...
Here we are offered to choose several forms of blanks. We choose the top option - a rectangular shape.
Here we enter the dimensions of our workpiece. Let me remind you that we are going to cut out the parts of a plywood stool on a standard sheet of plywood in the 2500 by 1250 mm format. Click OK.
Ready.
5. Settings for calculation of the cut sheet. We look for a button with sliders in the menu. Click. A window with three tabs opens.
Selecting a workpiece. In Panels Trim Cuts - specify the trimming of the sheet (if necessary) Usually used if the edges of the workpiece are uneven or damaged.
The box just below indicates the cutting width of the tool. If the cutter with which you plan to cut the parts is 6mm, then we indicate this value.
Second tab
Here you need to experiment. The most important is the top slider. If you leave it in its original (left) position, the program will practically not rotate the parts - the simplest calculation. If in the extreme right position, the miscalculation will take a very long time, but will be as effective as possible. Although approximately the same efficiency in our example will be achieved by positioning the slider as shown in the screenshot.
Well, everything is actually prepared to create a cut map. We are looking for a button with two gears - start cutting!
Rendering depth slider is approximately in the middle
There are practically no useful remains (for this stool).
The rendering depth slider is slightly to the right
With this cut, you can place another part of the seventh set on this sheet of plywood
Let's take a close look at what the program has drawn.
There is a cutting line for the workpiece. Cutting line – 6mm. The shaded area is unusable residues. Somewhere in the program settings I seem to have seen the setting of parameters for such leftovers: from what area of scraps is considered garbage.
The creation of a cutting sheet for curved parts for a CNC machine is completed. What to do next. You can just print it out. But we will export it to the same dxf format and transfer it back to the CAD program.
6. Export cut map
Well, from here you can create a control program for a CNC machine to cut six sets of stool parts from a sheet of plywood.
