FBE AutoCAD Page

Stephen Peter, S.Peter@unsw.edu.au

This tutorial has been prepared for students at the Faculty of the Built Environment learning AutoCAD. It has been placed on the Web to facilitate access by those students and because I believe others may find the material of use! Note that throughout this document I am using the character "" to symbolise the [Enter] and [spacebar] keys and the Right mouse button. Stephen Peter, 12 March 1999.

Introduction
	In this fourth (and final) AutoCAD tutorial you will learn how to plot drawings. In doing this you will learn about paper space and viewports. Let me comment before you begin, that in this tutorial I will be telling you to draw things (as much as possible), rather than explaining how to go about drawing them... read through the text carefully!
The drawing is quite simple, to allow time at the end to cover the issues relating to plotting.	You will draw a form study of Robert Venturi's "Fire Station - Number 4" in Columbus Indiana (1966), from Clark and Pause's "Precedents in Architecture", page 122. The drawing is quite simple, to allow time at the end to cover the issues relating to plotting.
	Please note that the dimensions used in this tutorial are neither accurate nor correct! I don't have access to an accurately dimensioned drawing of the building so I've guessed the dimensions...
	Set the drawing limits from 0,0 to 50000,35000; then set the units (set the number of decimal points to 0) and finally do a zoom-all.
Draw the "Construction" Lines
Before you continue, I'd suggest that you display the Object Snap Toolbar. Alternatively, you can get a "pop-up" menu of the snap modes by Shift-right clicking!	Create a CONST layer, set its colour and make it current. Draw a 18800 x 18800 rectangle (starting somewhere near the bottom-left corner of the screen).
	Draw a Circle, using the MIDpoint snap mode, pick the bottom edge of the square, and then using the ENDpoint snap mode, pick the top-right of the square.
	Next you will draw a rectangle to complete the golden rectangle. To do this we can use the bottom-right corner of the square for one corner, but the other corner is more difficult: you will use AutoCAD's point filters to take the x value from the circle and the y value from the original square!
The point filters that I'm introducing here are really useful - they often provide a way to "find" positions without having to type in numbers.	Start the rectangle command, then using the ENDpoint snap mode, pick the bottom-right of the square, then type: .X, using the PERpendicular snap mode, pick the circle to the right of the bottom of the square, then type: .Y, using the ENDpoint snap mode, pick the top-right corner of the square. This technique for drawing objects is very useful!
	Start the line command, then using the ENDpoint snap mode, pick the top-left corner of the square, using the MIDpoint snap mode, pick the right edge of the rectangle, using the ENDpoint snap mode, pick the bottom-left of the square, press to end the command.
Now you will use grip-editing to move the end of the lower line up 1800:	Pick the last line drawn (near the bottom-left corner), then pick the grip-box on the bottom-left corner (to move that endpoint), and type: @0,1800.
FROM snap mode icon The FROM snap mode is really useful for specifying objects that are positioned relative to other objects.	The entry will be shown as a circle about mid-way along the bottom of the square. Start the circle command, then select the FROM snap mode, then using the ENDpoint snap mode, pick the bottom-left corner of the square, then type: @9800,1400 1400. Here you are saying that the circle's centre is to be 9800,1400 from the bottom-left corner!
	Now, explode the original square and then offset the bottom of the square up 600, and then offset that line 1500 up. Then offset the left of the square 10000 to the right.
These are the major construction lines that will be used to set-out the plan. Your drawing should look like figure 1. If you haven't saved your drawing yet, then save it now!	Figure 1     The construction lines.
Draw the Walls
	Create a new layer called WALLS, set it's colour and make it current. Use Zoom Window to enlarge view of the plan.
	The walls will be drawn using the polyline command so that you can set the thickness of the lines after drawing them. But before drawing the walls, you will set a running-snap! The reason for drawing construction lines in the first place is to make it easier to draw the walls. To make it even easier, you will tell AutoCAD to automatically snap to line intersections, this saves you from having to specify the snap mode for every point (though you still need to set the snap mode when you want to use another snap mode or none).
Running-snap icon Be careful not to pick "insertion".	Select running-snap from the Object Snap toolbar (or type: OSNAP), then select "Intersection" from the dialog box and select "OK" to dismiss the dialog box.
	Figure 2     Path of exterior walls.
Polyline icon Note that the arc should be part of the polyline. NEArest snap mode icon	Start the polyline command and pick the first five points shown in figure 2, then type: ARC (the next segment of the polyline will be an arc), type: SECOND this specifies you will enter a "second" (& third) point, using the NEArest snap mode, pick the 6th point, then pick the 7th point to end the arc. Now type: LINE (to go back to drawing straight-lines), pick the 8th point, and finally press to end the command.
	Having demonstrated the running snap, let's now turn it OFF! Select running-snap again (or type: OSNAP), select the "Clear All" button (below the various snap options), and then select "OK".
	Turn the CONST layer OFF.
	Now you will change the width of the external wall to make it a thick line - the wall was drawn using polyline to demonstrate polyline editing! Did you turn the CONST layer OFF?
Many AutoCAD commands have 1 or 2 letter abbrieviatons! PE is short for PEDIT.	Select Modify - Object - Polyline (or type: PE), pick the external wall polyline. Spend a moment having a look at the various editing options - you can even fit a curved (spline) line to the polyline. Type: WIDTH (or simply: W), then type: 250, this is the new line-width. Press to end the command.
	Turn the CONST layer ON.

Paper Space
Venturi's building is quite interesting, but we don't have time to draw the whole plan -- and cover plotting....	In these tutorials, you have been drawing in what's called MODEL SPACE. The significance of this is that you use real-world sizes. When plotting, you can either specify a scale factor to plot the drawing at a particular scale or you can use PAPER SPACE.
	During the following step your drawing will disappear, don’t panic...
During this step your drawing will disappear, don't panic... "Tile" on the status area: Note that instead of typing "tilemode" you can type "ti".	Double-click on "TILE" (on the status area at the bottom of the screen), the "TILE" should become greyed-out. Alternatively, type: TILEMODE 0. When this setting is ON, AutoCAD displays multiple viewports beside each other, this allows you to have two views (of different parts) of the same drawing on the screen. When the setting is OFF, AutoCAD displays multiple viewports, but the viewports are allowed to overlap each other; also viewports can be moved, erased or resized like "normal" graphics! Turning tilemode OFF, also changes the "MODEL" space setting (next to "TILE) to "PAPER", indicating that you are now in "PAPER SPACE"!
	The advantage of paper space is that you can have numerous drawings (or views of the one drawing), each at a different scale; and you can draw text using "paper heights" rather than world heights.
Set the Paper Space Limits
Now we set the limits again! This time for the paper. If you aren't sure of a printer's margins do a test plot with diagonal lines that would go to the paper's edge and then measure the margins!	The plotter being used (at the Built Environment’s CADLab at UNSW) is a "HP DesignJet 200 Ink Jet Printer", this plotter has 17mm left and right margins and 5mm top and bottom margins, this is critical! When you lay-out your drawing you must remember that you can’t draw on this part of the page! My solution is to set the drawing limits to the area of the page that can be drawn on (the "plotable area"), and then draw a border equidistant from each of the paper edges.
Don't forget to do a zoom-all after setting the limits.	A landscape oriented A3 sheet is 420x297mm, this leaves a plotable area of 386x287mm. Set the limits to 0,0 to 386,287.
	Create a layer called FRAME, set it's colour and make it current.
	Draw a rectangle 20mm in from the edges of the A3 sheet; because of the plotter’s 17 & 5mm margins, draw the rectangle from 3,15 to 383,272, see figure 3. The rectangle is used to position "viewports" and then its layer can be turned OFF before plotting (if desired).
If you can't see the rectangle, select zoom-all. Figure 3     A3 sheet with limits and 20mm border shown.
Create a Viewport
If you want to change to size of the viewport to make it cover more of the "paper", use grip-editing to resize the viewport. You could use snap modes to "snap" the viewport to the drawing border.	Once in paper space you can create a number of views of your drawing, with each a different scale! But for this tutorial, you will create just one viewport; select View - Floating Viewports - 1 Viewport (or type: MVIEW ), pick a point towards the bottom-left of the drawing (the exact position doesn’t matter at the moment), and then pick a point towards the top-right of the drawing. AutoCAD should show a view of your drawing! This view is at no particular scale.
Return to Model Space
Notice that if you move the mouse cursor outside the viewport it changes back to an arrow!	Double-click on "PAPER" on the status area or select View - Model Space (Floating) (or type: MSPACE), the "PAPER" on the status area will change to "MODEL". Move the cursor around inside the viewport and you will see the normal cross-hair cursor appear. Usually, you want to have the view at a particular scale but sometimes you simply want a particular part of the drawing to plot and you don't care what it's scale is.
	Select zoom-window (or type: Z), enclose the entry circle in a selection rectangle, type: REGEN - this should force AutoCAD to recalculate the circle (and therefore display it better). If your drawing is like mine you will see that AutoCAD has made a mess of the line widths of the polyline around the arc...
Zoom-previous icon	Select zoom-previous (or type: Z P), this is a particularly useful zoom option, because it's very common to zoom in on a detail and then want to zoom back out. Of course, you could use zoom-in and zoom-out, or zoom-dynamic if you’re panning as well as zooming.
Setting the View Scale
Zoom-scale icon You could also type 0.01xp. Pan icon	To set the viewport to a particular scale, you need to express the scale, relative to the paper. If you want the view at 1:100 you use a scale factor of 1/100 (or 0.01). Select zoom-scale from the zoom flyout (or type : Z S), then type: 1/100xp), this will produce a view at 1:100, the "xp" means "multiplied by the paper". Select pan (or type: P), and drag the view until the "golden rectangle" is centred within the viewport, then press .
Paper Space Revisited
You may need to re-size the viewport to get the building fitting comfortably on the page - if you haven't already snapped the viewport to the border.	Return to paper space by double-click on "MODEL" on the status area or select View - Paper Space (or type: PS this is short for "PSPACE").
Text
	Select Format - Text Style, in the top section of the dialog select "New", click on OK (to accept the default name) then choose a font from the Font Name drop-down list - choose a true-type font (look for the TT icon), for example Arial, set the Height to 10, select "Apply" then select "Close".
	Create a TEXT layer, set it's colour and make it current.
Text icon The Text command can also be used to add text in MODEL SPACE, but the height of the text must be the text height x the plot scale, for example if you want the text 5mm high and the drawing at scale 1:100, the height must be 500.	Make sure you're in Paper Space, then select text (or type: MT which is short for MTEXT), you will now enter two points that will define the "boundary" of the text area. When you to type a paragraph of text, AutoCAD will wrap the text to fit inside the boundary! Pick a position below the bottom-left corner of the building, and a second point near the right edge of the 20mm border try to make sure there's enough height for the text...
Depending on the way AutoCAD is configured, you may enter the text into a dialog box or the word processor. This section assumes you are using the "Multiline Text Editor" dialog box.	Type: Robert Venturi’s Mother’s Fire Station #4!
	You can change the properties of the text (within the dialog box) by selecting the property that you want to alter: select "Mother's" then select the colour drop-down list (it should show "ByLayer" at present), select a colour, then click on "OK" to dismiss the dialog box.
	This text is obviously wrong.
Properties icon	Select properties, pick the text and press , AutoCAD will display the Modify MText dialog, take a moment to look at the various options available...
	Click on the "Full Editor..." button (beside the text), highlight "Mother's" (include the space after the word), press the "Delete" key, select "OK" twice - to dismiss the Editor and then the Modify dialog.
You can also use Grip Editing to change the text area!	If the text has wrapped onto 2 lines, select properties and then the text again, then increase the Width (try adding 10 for each letter on the second line), then dismiss the dialog.
If necessary, move the text so that it is better centred under the "Golden Rectangle".	Figure 4     The Completed Drawing.

Creating the Plot File
	Before plotting, turn OFF the FRAME layer - this is optional, but if your viewport and your 20mm border are not the same, then you’ll have a mess!
Print icon	Select print or select File - Print (or type: PLOT), the Plot Configuration dialogue box will be displayed. This complicated dialog box has six areas: Device and Default Information Pen Parameters Additional Parameters Paper Size and Orientation Scale, Rotation, and Origin Plot Preview
The plotting instructions here are specific to UNSW - if you're plotting elsewhere you will need to ask your "local expert" (and if that's you then read throught the AutoCAD and printer manuals and make some test plots)!	The "Device and Default Information" section will show the currently selected output device, if it doesn't list the DJ200 then click on the button and select "HPGL2 - DJ200" from the list of devices.
	In the "Additional Parameters" section, make sure "Limits" and "Plot to File" are selected. Then click on "Filename", change the Drive to Q: (the print queue), if your drawing name is not distinct the you should change the plot filename to something unique (and short), finally click on "Save" - this saves the filename it doesn't do the plot!
	In the "Paper Size and Orientation" section make sure "MM" is selected, if the plot area is not equal to your limits (386 x 287) then select "Size..." and choose the correct paper size or type the dimensions as a USER size.
	In the Scale section, set the scale to 1 = 1 and make sure "Scaled to fit" is not selected.
	It’s usually a good idea to do a preview! In the "Plot Preview" section, select "Full" and then click on "Preview". The preview should show the drawing! When you are ready, press to return to the plot dialog.
	Click on the "OK" button near the bottom of the Plot Configuration dialog box. AutoCAD will then create the plot file (which should only take a moment because your drawing is very simple). The plot file will be "tut4.plt" or whatever your drawing is called, with the ".plt" extension.
Note that the "paper" in the preview is in fact the drawing's limits, which were set to the area of the paper that the plotter can draw on! If something looks wrong with the preview, check that all the settings are correct and if they are, then cancel the plot and check that your limits are correct. If you still can't work out what's wrong call the tutor!	Figure 5     Plot Preview.
	That's all folks! Save the drawing and exit AutoCAD!
Plotting
In addition to this text, refer to Jim Plume's "Notes on using the HP Designjet 200 iInk Jet Ploter".	Plotting this tutorial is strictly optional. But, hopefully at least one drawing will be plotted from each group. This will allow you the opportunity to see it done!
	Each plot costs $1.00, using your UNICARD photocopy card.
	The dj200 plotter is located in Lab 3 (Rm 3034), the ON/OFF switch is on the bottom-left of the front. If the lights on the right are dark then turn the plotter ON.
	Go to the computer beside the plotter and follow the instructions there!
	Take the paper from the cupboard to the left of the plotter and carefully load the paper into the plotter: hold the sheet with its short edge facing the front of the plotter, the right edge of the paper must be between the dotted lines and exactly straight. Carefully push the paper up into the plotter until the plotter grabs the sheet. If the paper is not straight the Error and Load Media lights will blink, press Form Feed, remove the sheet and try again. If the paper is loaded correctly the Ready light will come on.
	When the plot is complete, carefully remove the paper from the plotter and leave for one minute to dry.
Conclusion
	These tutorials have given you the basics of (2 dimensional) drawing using AutoCAD, I sincerely hope that this knowledge serves you well and that you continue to increase your knowledge and understanding of AutoCAD (and CAD in general).
	The first tutorial introduced AutoCAD and got you to focus on the interaction on the command line between you and the program. In addition, you used toolbars to select drawing commands and learnt a bit about snap modes.
	The second tutorial introducing "real" coordinates; and then focused on editing, using the array command to copy and rotate graphics objects, using explode and erase to modify, and then changing linetypes.
	Tutorial three is the longest and most difficult. It (like the second tutorial) focused on editing, using offset, array and mirror, in addition to fillet, trim, break and extend. It also introduced the concept of layers which is vital to a proper understanding of CAD.
	Finally, this tutorial introduced the concepts of model & paper space, viewports, plotting and text.
	These tutorials cover most of the basics of architectural drawing in AutoCAD, but there is much that is not covered: dimensioning and 3D, for starters(!), and while I have tried to show you how you might approach drawing a building, I haven’t directly discussed this at all!
	If you’re asking where do I go from here? - that's great - read up on the concepts of CAD and AutoCAD. There are numerous books available on the topic and more appearing all the time. In my opinion, keep away from books that seem to be thousands of pages long, you hopefully have access to the AutoCAD manuals, use them as reference materials, if necessary. Look instead for books that give you things not covered in the manuals! By reading books that cover how CAD can or should be implemented or managed in an office, I think you'll learn more about CAD related issues than you'll learn from a thousand pages of reference manual.

FBE AutoCAD Page

Last Update : 26 April 2000 Major Revision : 09 October 1998 SEARCH . FBE SITEMAP		Disclaimer . Webmasters Page Contact : Stephen Peter Email : s.peter@unsw.edu.au