Metric of solid

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When calculating the dimensions of solid parts (Solid 3d), my plugins calculate and preserve the so-called metric of solid. The metric allows you to distinguish the details from each other and find the parts mirror to each other. If all the data in the metric is the same - then the program will assume that it is the same part. Although in fact there may be a mistake, because the accuracy of the calculations is limited.

Use the Lay, Saw, AVCNum or SolSize commands to measure solids. All these commands will record the results in xData of solids and you will see them in the Metric section if you install the A>V>C> Properties Palette. The metric consists of three sections, each of which can be collapsed in the panel if it is not needed: Calculations, Covers, Edge Bandings.

Calculations

All these properties - read only. And they will all be zero, until the solid measurement is made. Call one of the commands: Lay, Saw, AvcNum or SolSize. Then the solid will be measured and the dimensions will be retained within the solid (in xData).  Now program can show the metric. Any change in solid, as well as in moving and copying, metrics will be reset to zero. And again you will have to call the measurement command. Automatic measurement is not implemented because it strong loads AutoCAD and takes a long time. After you change the properties of the SWEEP as required manually call one of the measurement commands too.

Covers

The section contains a list of covered faces. The list always contains the front and rear of the part. The remaining surfaces are listed only if you have already assigned them a cover material. There are three columns in the list:

The program can highlight the surface in the drawing that the mouse pointer is hovering over in the table. However, this resets the highlighting of the selected solids. If this bothers you, you can turn off the highlight.

Edge bandings

The section contains a table of the edges of the part. When measuring solid, the program bypasses the outer perimeter of the front plane and compiles a list of faces adjacent to it. These faces are excluded from the list of covers.The edges are always listed in traversal order, starting from the bottom left point of the contour. That is, the left side of the rectangle is edge number 1. This means the left side of the part laid out by the Layout program (LAY). The position of the edges in the initial assembly does not matter; the LAY usually turns the parts over (depending on the settings and order of the surfaces in the internal structure of the solid). The rotation of parts with texture = “across” and the mark “mirror” are also taken into account. The number of edges is not limited, it will not necessarily be 4. The program is not designed to work with complex parts, in which the front surface is cut into parts by dadoes, etc. Only faces adjacent to one main front face will be included in the list, even if this is the edge of the dado. In Common Options, you can enable and configure the letter names of the ends (L-left, T-top, and so on). Then the ends at the edges of the contour, directed strictly along X and Y, will receive a letter instead of an index. If you select more than one part in a drawing, the program usually shows only these 4 main edges. Since the part in the assembly is unfolded differently than on the layout, it is better not to rely on these names, but to look at the highlighting of the surface in the drawing when moving the mouse over the table.

There are 4 columns in the table:

Edge numbers are used to index substitutions. If you need to write the material of the longest edge to the table, then use index 1 - %edgemat1% substitution. Read more here.

Metric measurement rules

The measurement program is made for use in the design of sheet material parts. These parts always have a main plane, on which it is determined how to lay out the part. This algorithm does not work for spheres, tors, shafts and sculptural details. The program can measure the simplest sweep of bent parts, but they must be specially marked. To do this, you need the Names plugin.

The program is looking at each solid front (main) surface. This surface should be in the XY plane on the LAY command. When choosing a front side, surfaces are given an advantage in the following order of priorities:

Color marking and top-side priority can be turned off in Common Options.

In addition, the part rotate around Z so that the longest edge of the solid extends along the X axis (or Y if the Texture property is = Across). When searching for the longest edge, the priority of the right angles is taken into account. Those a rectangular triangle will not be laid along the hypotenuse. Only after laying and rotating the program measures the smallest box, which will fit solid. Dimensions of this box along the axes XYZ are considered the dimensions of the part. The largest dimension is length, medium - wide and least - thickness. The volume is also calculated only after the layout. AutoCAD can give different volumes when you rotate the same solid. The distance from the center of the box to the real center of mass of the part is considered an indicator of asymmetry. For simple boxes, this distance is zero. If the parts have identical metrics, but different directions of asymmetry - then it is considered that the parts are mirror to each other.

Note that the area and perimeter are not calculated for the entire solid, at the same time for one largest flat surface, which the program considers the base. Usually this is the area of the facade of the part.