Archive for the ‘CAD Drafting’ Category

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Let’s Go Design in 3D

02/17/2010

2D drafting methods are not able to relay the quality and quantity of design information because 2D methods will always rely on human interpretation or visualization skills to interact with a 2D design.  This is always difficult for non design staff and almost impossible for computer systems to extract this kind of information, because computers do not have the ability to interpret.

As a result, many human errors can occur with traditional 2D design methods.  In the past problems such as component collisions, incorrect quantities or parts that don’t fit, would happen because a designer who works in only 2D is forced to hold much of the information mentally. 

Reducing human error by using the 3D modeling design methods minimizes the need for re-work because the design quality is greatly improved. Using 3D design modeling greatly improves design quality because it is a more complete process than 2D design.  One most important thing about 3d CAD design is that people can have view of the model from all possible dimensions.  It is a highly detailed drawing of what your concept will look like as a finished product. 

Whether you’re designing a new innovative product, creating technical manuals, or requesting quotes from suppliers, 3D CAD design is extremely powerful.  But when a 3D CAD design is transformed into a physical 3D print or job shops’ product prototypes, there is no substitute for the tactile and visual feedback a physical model provides to all participants in the design process.  

Mechanical Designers usually share their work space with drafters or other engineering technicians in quiet, well-lighted surroundings separated from production areas.  Working from drawings, sketches, planning sheets, and other engineering and shop data, tool designers must visualize the Design, do the panning, document and verify every step of the way. 

Because of reductions in defense spending, jobs for mechanical engineering type work will decrease; however, the employment of mechanical engineers is expected to grow about as fast as the average for all occupations through this year due to the demand for new and more complex industrial machinery and tools resulting from the development of more sophisticated automated production processes.

The use of 3D modeling technology is essential when you want to develop a superior product.  Such a product will not be influenced by human interpretation. Furthermore, it will look like the final model.

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The other Solidworks drawings formats.

12/14/2009

Detached drawings:
Detached drawings are designed so you can open and work in drawing files without the model files being loaded into memory or even being present.
You can save regular drawings as detached drawings, and vice versa.
With a drawing open, File>Save As. Change the Save as type to “Detached Drawing (*.slddrw)”.

To save the sheet format:
Sheet format files have extension .slddrt and are located in \solidworks\data.
Custom properties in the document are saved with the sheet format and added to any new documents that use the format. Click File, Save Sheet Format You can overwrite standard formats or create custom formats.

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SHEET METAL

11/29/2009

Article contents:
Sheet metal drawings and fabrication
Characteristics of sheet metal bends
VERY VERY VERY…EXTENSIVE.

http://solidmasters.com/Sheet%20Metal.htm

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convex curve

10/21/2009

A change in the angle of inclination of a belt conveyor where the center of the curve is below the conveyor.

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Dash Number (Part Suffix).

10/05/2009

A number suffixed to a drawing number to identify individual parts or assembliesdepicted and controlled by the drawing.

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Configuration Item.

10/05/2009

 An aggregation of hardware, firmware, software or any of its discrete portions  whichsatisfies an end use function and is designated for configuration management.  CIs may vary widely incomplexity, size and type; from an aircraft, ship or electronic system to a test meter or round of ammunition.During the development and manufacture of the initial (prototype) production configuration, CIs are those itemswhose performance parameters and physical characteristics must be separately defined (specified) andcontrolled to provide management insight needed to achieve the overall end use function and performance.  Anyitem required for logistic support and is designated for separate procurement is a CI.  (MIL-STD-973)

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CI. Configuration Identification

10/05/2009

  The selection of the documents to comprise the baseline for the systemsand CIs involved, and the numbers and other identifiers affixed to the items and documents.  The approveddocuments that identify and define the item’s functional and physical characteristics in the form of specifications,drawings, associated lists, interface control documents, and documents referenced therein. The configurationidentification is developed and maintained through three distinct evolutionary increasing levels of detail, eachused for establishing a specific baseline.  (MIL-STD-973)

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ACI. Allocated Configuration Identification

10/05/2009

The ACI is the technical documentation governing andspecifying the performance, physical and interface requirements for CIs that are part of a higher level CI, typicallya system; this documentation is in the form of specifications, drawings and associated lists, and documentsreferenced therein, and is usually prepared during the validation phase. If there is no validation phase, the ACImay be prepared during the initial part of the full-scale development phase. Like the FCI, the ACI included testprovisions to assure all of the specified requirements are achieved by the developed CI.

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REVISIONS STATUS APPLIED TO THE DRAWING

09/28/2009

The revision status of a drawing is identified by an upper case letter. The first change issued in the Revision History block or the reference to the Revision Authorization Document (ADCN or DCN) is identified by the letter “A”. Each successive change uses the next letter of the alphabet in sequence, except the letters “I”, ”O”, ”Q”, “S” and “Z” are never used. Upon exhaustion of the alphabet, revisions are identified by letters “AA”, “AB”, “AC”, etc., then “BA”, “BB”, etc.. Revision letters shall not exceed two characters. The letter “X” is reserved for recording revisions to a drawing prior to its release. Changes beginning with “X1” and following with “X2”, “X3” etc for each successive change. The use of a dash “-” shall be used only for the initial release of a drawing. Initial release does not constitute the need for a revision letter and the Revision History block may be left blank

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Reviewing Detailed Drawings.

09/26/2009

Reference ASME Y14.3M. Check the following: Detailed drawings must completely depict the entire part or assembly shown. Ensure that there are sufficient views to adequately define the item. Ensure that all dimensions are taken from physical features. Reference ASME Y14.5M-1994. Detail drawings should not show the dimensions for hidden lines. Reference ASME Y14.5M-1994. Ensure that datum planes are properly defined. Reference ASME Y14.5M-1994. Ensure that mono-detail drawings depict only one item.

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Virtual Condition

09/26/2009

A constant boundary generated by the collective effects of the featuresize, its specified MMC or LMC material condition, and the geometric tolerance for thatcondition.

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Regardless of Feature Size (RFS)

09/26/2009

The term used to indicate that a geometric toleranceor datum reference applies at any increment of size of the feature within its tolerance limits.RFS is the default condition unless MMC or LMC is specified. The concept is now thedefault in ANSI/ASME Y14.5M-1994, unless specifically stated otherwise. Thus the sym-bol for RFS is no longer supported in ANSI/ASME Y14.5M-1994.

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Revision Table

09/24/2009

Insert a revision table into a drawing to track document revisions, including revision symbols. In addition to the functionality for all tables, you can select:

  • Revision symbol shapes
  • Alphabetic or numeric sequence

The latest revision also appears under REV in the lower-right corner of a sheet format.

In drawings with multiple sheets, you can set options to activate a revision table on the first sheet only, link the tables on all sheets, or keep the tables independent of each other.

View a full article

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Text font, edit lines and arcs.

09/24/2009

The operation is called “dissolve sketch text” To dissolve sketch text into separate sketch entities: In an open sketch, right-click the text (the pointer changes to when it is over the sketch text) and select Dissolve sketch text. The sketch text is converted into non-text sketch entities (for example, lines, arcs, splines, and so on).

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K Factor / Set Back

09/21/2009

Set Back (Applicable To Closed Angles Only).  This is the deduction made in the length of a flat pattern development corresponding to the amount of material saved by bending around a radius instead of a sharp corner.

See the full stories on this topic…

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Basic Dimension:

09/21/2009

A numerical value used to describe the theoretically exact size, orien-tation, location, or optionally, profile, of a feature or datum or datum target. Basic dimen-sions are indicated by a rectangle around the dimension and are not toleranced directly orby default. The specific dimensional limits are determined by the permissible variations asestablished by the tolerance zone specified in the feature control frame. A dimension isonly considered basic for the geometric control to which it is related.

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Reference Dimension:

09/21/2009

A dimension, usually without tolerance, used for informationpurposes only. Considered to be auxiliary information and not governing production orinspection operations. A reference dimension is a repeat of a dimension or is derived froma calculation or combination of other values shown on the drawing or on related drawings.

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Virtual Condition:

09/21/2009

A constant boundary generated by the collective effects of the featuresize, its specified MMC or LMC material condition, and the geometric tolerance for thatcondition.

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Maximum Material Condition (MMC):

09/21/2009

The condition in which a feature of size containsthe maximum amount of material within the stated limits of size. For example, the lowerlimit of a hole is the minimum hole diameter. The upper limit of a shaft is the maximumshaft diameter.

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Degrees of Freedom:

09/21/2009

The six directions of movement or translation are called degrees offreedom in a three-dimensional environment. They are up-down, left-right, fore-aft, roll,pitch and yaw.