6/30/2009. June 30, ANSI Standard Y14.2 provides conventions for line usage in technical drawings.

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1 June 30, 2009 Know the basic line conventions for drafting Create and manage drawing layers Set up and use a variety of line types Draw objects on separate layers Filter a list of layers Use the Design Center to copy layers and line types between drawings Make prints of your drawings. Hidden Lines Section Lines ANSI Standard Y14.2 provides conventions for line usage in technical drawings. Line qualities, (type, width, etc ) are assigned in Autocad assigned in Autocad. Line types may be modified to accommodate different scale drawings. Object Line Center Lines Hidden Line, Used to show features that are obscured in a view. This line is a.3mm thick, dashed line, ideally it will be composed of q/8 long dashed with 1/16 spaces. Object Line, Used to show visible features, and are the most commonly used type of line. They are.6mm thick Extension Line, Used to show the extent of a dimension. It is a continuous,.3mm thick line which should always have a 1/16 gap between the object and its start. 1

2 Center Line, Used to locate cylindrical features Cutting Plane Line, Used to locate a cutting plane, from which a section view will be created Short Break Line, Use to show a broken out detail. This is an irregular shaped,.6mm Phantom line, thick line Used to show projected paths, repetitive features, and alternate positions Layers are used in Autocad to organize the drawing s components and assign the appropriate line types. By default a new drawing will only contain one layer. The Autocad user will create new layers for the various line types used Layers when used correctly will increase productivity Layers may be used to assign different colors and different line weights for each line type. Changes can be made to a given layer to affect all objects on the layer, but leave the other layers unchanged. Layers may be turned off or frozen to display information as needed Each layer may be plotted, (or not), in different colors or line weights Information may be grouped on different layers, (Example: Electrical wiring might be on one layer, while plumbing information might be on a different layer, and framing information on yet another layer Mechanical, Civil, Architectural and Electronic drawings will all be organized with different types of layers For example, on a mechanical drawing object lines might be black,.6mm thick and located on a layer named Object. Hidden lines might be green,.3mm thick and located on a layer named Hidden. Architectural and Civil Engineering drawings may contain hundreds of layers. Separate layers might be designated for plumbing systems, HVAC systems, site plans, plumbing fixtures, etc Different firms will have different conventions. 2

3 Properties to include: Color Line Type Line weight Name On / Off (Frozen) Locked New Layer Button Set Layer Current Use to access Layer Properties dialogue box Layer Properties Delete Layer Once a new layer is created the layer properties dialogue box will appear and the new layer may be named, the line type and color chosen. By default new layers will be on, unlocked and unfrozen. A yellow light bulb indicates that the layer is on and the layers contents may be viewed. The gray light bulb indicates that layer is off and the contents may not be viewed. New Layers will by default be named Layer 1, Layer 2, etc Layer Properties On/ Off Layer toggle Freeze/ Thaw Toggle The sun icon indicates that a layer is unfrozen and it may be made current, and objects within it maybe selected and modified. The snow flake icon indicates that the layer is frozen. The layer may not be set to current, and the objects contained within the layer may not be selected and modified The objects created will be contained within the layer that was current at the time they were created. Layers may be made current from within the Layers may be made current from within the layer properties dialogue box, by selecting the layer and clicking on the green check box. 3

4 Green Check will indicate which layer is current The Layer control pull down box may be used to change the current layer and change its properties. Simply select the layer that is to be current from the pull down menu Layer Control Pull Down Box The default layer color is black Different colors to allow the user to easily distinguish which objects belong on a given layer To change the color simply click on the black color icon and select a new color Select a Color Click on Line type listed for layer Select load from the select Line type dialogue box. Note: All of the line types used in the drawing will be listed in the select line type dialogue box Click on Load Button to select a different line type The standard hidden, dashed, phantom, fence, center lines are all available within the standard installation. Default Selection of Line Types Customized sets of line types are available for special applications To select a line weight click on the line weight icon, and choose the appropriate weight line from Lineweight dialogue box Note : Typing Lineweight, Lweight,or LW at the command prompt will also open the lineweight dialogue box. 4

5 The Line weight scale option is used to increase or decrease the number of dashes or spaces for a particular layer The default line weight scale is 1. Values for line weight scale greater than 1 will result in larger dashes and longer spaces Values for line weight scale less than 1 will result in shorter dashes and shorter spaces. Line Type Scale may be changed by typing LTSCALE at the command prompt or accessing the objects properties The Line weight settings may be accessed by typing Lineweight, or Lweight at the command prompt. Units for line weight are usually millimetere, but can be set to inches. Typically the lines displayed in the Autocad work area are not shown to the true lineweight, but are plotted to the set line weight. The line weight settings can be set to display the true line weight in the Autocad work area or to a percentage of the line weight Create a new drawing Create a new layer named object, black -.6mm object Create a new layer named hidden line, blue -.3mm hidden Create a new layer named center line, red -.3mm center line Create a new layer named phantom line, green -.3mm phantom line Plot Icon The plot style column of the layer properties dialogue box lists the poly style that is assigned to the layer. By default the plot style setting is disabled and all lines will b plotted. The Autocad user may set a given layer to no plot, to prevent it from being plotted. To set the layer to not plot double click on the printer icon in the Plot Style column. No Plot Icon 5

6 By default new layers are named Layer 1, Layer 2, etc. It is helpful to name the new layers appropriately, (Wall, Electrical, etc ) It is also helpful to provide a layer description. To provide a description double click on the space provided under the description column When the description area becomes highlighted type in the description. Note: The description may be changed at anytime by double clicking on the existing description and replacing the text. The layer s name may also be changed at any time, by double clickin on the existing name and typing the replacement text. The width of the columns in the layer properties dialogue box, are narrow, and often cut off a portion of the layer description or name To maximize a column, right click on the column heading and select maximize column from the short cut menu To resize the columns,move the cursor over the vertical line dividing the columns and drag to resize and widen the column Layer Properties Dialogue Box Drawing Templates may be used to save time, by providing the needed drawing limits, layers, units, line weight symbols, and title information. To create a custom template, simply save the drawing with the correct layer settings, limits and text as an Autocad *.dwt file When starting the next new drawing simply browse for the template file. The Design Center will be found at the far right of the Blocks and Reference Tab May also be accessed by typing ADCENTER, or ADC 6

7 The Design Center is used to access blocks, line weights, layers, and dimensioning styles from other drawings. This is a time saving tool. Open New Drawing Access Design Center Browse for Autocad File created in last activity Select Layers folder Select each layer seperatly to add ot too the newly created drawing. When a drawing contains many layers it may be difficult to display the long list and quickly view all of the information A filter may be used to limit the amount of information displayed. Filters are created to group related information together New Layer Filter Properties Icon New Group Filter Button, Accessed from the Layer Properties Dialogue Box Click in each category to set the status for the layer to be included To create a group filter, click the new group filter button and name the new filter. Add the required layers to the group. 7

8 The layer s state is used to determine if a layer may be viewed, plotted or edited To create a new layer state clickon the Layer States Manager Icon The new layer state will be represented in a column Typically the designer will draw in model space, but plot from paper space. The Autocad user may toggle from model to paper space by clicking the model buttonon the status bar Paper Space will allow the Autocad user to view the title block, and border. It also allow the user to scale the object in the paper space so it is to correct scale and centered. Drawing Problems, Page 171, Problems 5.1,5.3 and 5.9 8