Home > ZWCAD > Introduction and Installation >
Comparing ZWCAD drawing with manual drafting

May 20, 2011

ZWCAD greatly reduces the time and effort it takes to create and revise drawings. Not only can you produce accurate drawings faster, you can also reuse the information in your drawings.

These are the primary reasons for making the transition to CAD from traditional, manual drafting on paper.

 As with any tool, however, to use it effectively, you need to be familiar with some of the special features, functions, and concepts of CAD. If you are familiar with manual drafting, you'll find some conceptual similarities in CAD as well as some differences.


Drawing to scale

In traditional, manual drafting, you usually determine the scale of the drawing before you even start to draw, because you are working with a sheet of paper of a fixed size. You may have to reduce or enlarge the entity you are drawing to fit within the confines of the paper.

When you create a drawing in ZWCAD, you draw everything full size. You determine the type of units in which your drawing is measured. If you are drawing a building, 1 drawing unit might equal 1 inch. If you are drawing a map, 1 drawing unit might equal 1 mile. Your drawing environment and the CAD drawing file itself are not limited to the size of a particular sheet of paper.

\

 

1 drawing unit equals 1 inch.  1 drawing unit equals 1 foot.


As you draw, you can use commands such as Pan and Zoom to work on different part of the drawing and to magnify the display of the drawing to view small details. These commands have no effect on the actual size of the entities in your drawing; they affect only the way the drawing is displayed on your screen. Only when you print or plot your drawing do you need to set the scale so that the printed drawing fits within a specific paper size.


Using tools

In manual drafting, you use tools such as pencils, rulers, T squares, templates, erasers, and so on. When you create a drawing in ZWCAD, you use a mouse instead of a pencil, and you use the mouse to select other tools-commands you select from a menu or a toolbar.

You use some tools to create basic entities, such as lines, circles, and arcs, and other tools to modify existing entities (for example, to copy or move them or to change properties such as color and linetype).


Organizing information

In traditional drafting, you often separate elements such as walls, dimensions, structural steel members, and electrical plans onto separate, translucent overlays. When you want to print the working drawings, you can create several different drawings by combining different overlays.

When you create a drawing in ZWCAD, you use layers to organize elements in a similar manner.

However, the layers feature in CAD offers numerous advantages over physical transparencies.

The number of overlays you can combine to print a manually drafted drawing is limited by the printing process. There is no such limitation in CAD. With ZWCAD, you can define an unlimited number of layers, any of which can be visible or invisible at any time.

You can name each layer and assign each its own color, linetype, lineweight, and print style.

You can also lock individual layers to ensure that information on those layers isn't altered accidentally.

\

Use layers to organize drawing information.


Drawing accurately

When you create a manual drawing, ensuring accuracy typically requires a lot of manual calculations and rechecking. By contrast, ZWCAD offers a number of drawing aids that ensure accuracy from the start. For example, you create and modify entities based on an underlying Cartesian coordinate system. Every location in the drawing has its own x,y,z coordinates. You can also display a grid as a visual reference to your coordinate system.

 \

Each position in the CAD drawing has its corresponding x,y,z coordinates within Cartesian Coordinate System. Point 5,2,0 is 5 units to the right (along the x axis), 2 units up (along the y axis), and 0 units (along the z axis) from the origin (the 0,0,0 point) Settings such as snap and entity snap allow you to draw accurately without specifying coordinates.


The snap setting forces the selected points to adhere to the grid increment or to any other increment you set. Entity snaps let you snap to precise geometric points on existing entities— for example, the endpoint of a line or the center of a circle. Another setting, orthogonal, constrains lines so that they are drawn parallel to the vertical and horizontal axes. Polar tracking and object snap tracking help you draw objects at specific angles or in specific relationships to other objects. When you turn on polar tracking and object snap tracking, temporary alignment paths help you create objects at precise positions and angles. You will discover techniques that make specific design tasks easier.

\

Paper based drawings lack the high degree of accuracy possible when using CAD. Lines often overlap or fail to meet adjacent lines.

\

Snap and entity snap force the cursor to adhere to a specified increment or attach to key geometric points on existing entities. You can also constrain lines to vertical and horizontal axes.


Drawing efficiently

In paper based, manual drafting, you often have to redraw the same entity several times at different scales or from different vantage points. You may also need to redraw the border and title block on each new sheet.

One of the most powerful features of ZWCAD is that when you create a drawing, you can reuse individual entities, borders, and title blocks as often as you want. You need draw an entity only once; the final printed drawing can show the entity at several different scales and viewpoints.

You usually begin drawing in model space on the Model tab, creating the drawing (a floor plan, a map, or a three dimensional part) without regard to the final layout on paper. When you are ready to print your drawing, you have the option to switch to paper space on a Layout tab, where you lay out the drawing as you want it to appear on a sheet of paper.

\

You create the basic drawing in model space on the Model tab.
 

\

 

When you're ready to print or plot your drawing, you can switch to paper space on a Layout tab, where you provide a layout of the drawing as you want it to appear on a sheet of paper.


Reusing CAD drawings and entities

When you create a paper drawing manually, you can draw repetitive symbols by tracing a plastic template. After you draw a symbol in ZWCAD, you can reuse that symbol without having to redraw it. You simply save the symbol as a block. You can then insert copies of that block anywhere in your drawing. You can also save the symbol as a separate drawing for use in other drawings.

\

You can draw a symbol one time, save it as a block, and then insert multiple copies of that symbol anywhere in your drawing.


In addition, you can reuse entire drawings and insert individual drawings into other drawings.

You can also use an external reference, which acts as a pointer to another drawing rather than a copy of the entire drawing. Using an external reference has an added advantage: when you update the externally referenced drawing, each drawing that references it can be automatically updated.


Making changes

To make changes to a paper drawing, you erase and then redraw. With ZWCAD, you use commands to modify entities in the drawing. You can move, rotate, stretch, or change the scale of entities. When you want to remove an entity, you can delete it with a single click of the mouse. If you make a mistake while creating or modifying your drawing, you can easily reverse your actions.

\

You can easily change an entity using commands such as move, rotate, stretch, and scale instead of redrawing the entity.


 

PrintPrint Get a PDF version of this webpage PDF
2013 ZWCAD Software Co., Ltd. All rights reserved. | About ZWSOFT | Privacy Policy | Terms and Conditions | Contact us | Site Map