Understanding Plastics, Stone Materials, Ceramics, and Technical Drawing

Plastics

Plastics can be defined as a group of synthetic materials of organic origin, easily moldable with heat and pressure.

Thermoplastics

Thermoplastics are plastics that melt above a given temperature, which allows their conformation. Once molded, they can be recovered; that is, they can be easily recycled because heating them again (between 80 and 100°C) softens them, allowing the process to start again.

Thermosets

Thermoset plastics are characterized by the fact that once molded, they harden and remain unchanged when subjected to heat or pressure again.

Elastomers

Artificial elastomer plastics are materials obtained by chemical synthesis.

Joining Techniques

  • Adhesive bonding: Methods for cohesion using adhesives.

Recycling of Plastics

  • Mechanical recycling
  • Energy recovery
  • Recovery of constituents

Stone Materials

Stone materials can be defined as solid and hard aggregates formed by a group of minerals commonly used by humans as a building material.

Natural Rocks

  • Granite
  • Slate
  • Marble

Artificial Rocks

Artificial rocks are created by humans using small pieces of natural stones joined by cement or mortar.

Ceramics

Ceramic materials can be defined as all materials obtained from previously molded and baked clay. There are two types: porous ceramics and waterproof ceramics.

Standardization in Technical Drawing

Standardization is the set of conditions or rules governing all elements involved in graphic representations.

Dimensioning

Dimensioning consists of general rules and principles designed to clarify and precisely define the shape and dimensions of technical drawings.

Symbols

Symbols consist of all letters, numbers, and signs that accompany the technical drawing.

Lines in Technical Drawing

  • Thick continuous lines: Used for visible borders and edges.
  • Thick dashed lines: Used to represent hidden edges.

Dimension and Reference Lines

  • Auxiliary Lines: Fine solid lines indicate the range to be defined.
  • Dimension Line: Thin continuous line parallel to the element’s edge to be measured.
  • Arrowhead: Located at the ends of the dimension line, indicating precisely the enclosed extent.
  • Dimension Value: The numeric value located in the center and above the dimension line indicates the true dimension of the element. When not specified, the unit of measurement is millimeters.

Dimensioning Systems

  • Series Dimensioning: Dimensions are arranged one after the other.
  • Parallel Dimensioning: Dimensioning by overlapping levels.
  • Dimensioning from a Common Origin: The piece is measured using a common reference point, and it can be done in parallel or with overlapping levels.
  • Combined Dimensioning: Used when both series and parallel dimensioning are present in one drawing.
  • Dimensioning by Coordinates: Used in certain manufacturing processes.

Scales

A scale is the relationship between the magnitude of a design and the actual dimensions of the object.

Scale = Measurement of the object on the map / Measurement of the object in reality

Perspective

Perspective is the attempt to draw, in a single representation and on a flat surface (which only has two dimensions), the fact that objects have three dimensions.

Axonometric Perspective

Axonometric perspective is a representation system that allows you to create objects giving the sensation of volume on a surface that possesses only two dimensions (length and width of the paper). One type is *Cavalier perspective*.