HATCH (poché)

This is an exercise in using the semi-automatic dimensioning process in AutoCAD. It will require starting a new AutoCAD drawing file using a template drawing as a base drawing, drawing a plan of a simple room and "hatching" the walls, drawing lines and circles, working with layers and text, and using the dimensioning commands. The end result will be a drawing which will be printer plotted on the HP Laser Jet printer.

  1. Open a new drawing using the Triton A template.
  2. Immediately save it to your folder on the M: drive with name of "today's date <your initials> 3." Like this 2006 02 18 FEH 3.DWG
  3. Draw a room with internal dimensions of 20 feet wide in the east-west direction and 15 feet deep in the north-south direction with one corner diagonally cut off, and with a wall thickness of 8". You will be dimensioning the interior of the space.
  4. Draw a single left-hand reverse bevel 3'-0" wide door 1 3/4" thick at the center of the diagonal wall on the "A-DOOR" layer.
  5. Draw a circular table in the room on the "A-FURN" layer with a radius of 3'-0".
  6. Make A-WALL-PATT layer current. Draw lines from the corners of the diagonal walls, as shown on the example attached, to separate the diagonal sections from the orthogonal sections of the walls during the hatching. Type Bhatch <RET> or select the hatching icon from the Toolbar (it is the icon that looks like a trapezoid with a diagonal hatch pattern in it). Click on the "Type" pull-down box and select "User Defined". Change the angle to 45.00. Change "Scale to 3. Select the "Add:Pick Points " button. At the "Pick internal point" prompt, pick a point inside the lines defining the orthogonal walls. AutoCAD will examine the enclosed area and if it finds that there are not openings within that area, AutoCAD will automatically place a temporary polyline inside the boundaries enclosed within the wall thickness. When you see the dashed line and agree with AutoCAD that this is the boundary within which you want the hatch pattern to appear, hit a <RET>. Then click on the "Preview " button. When you are done being amazed at AutoCAD's functionality, hit another <RET>. Hit another <RET> to bring the "Bhatch" command immediately back so that you can now hatch the diagonal portions of the walls. To hatch the diagonal wall area, do the same thing as outlined above, but re-set the user-defined hatch pattern angle to 0 degrees (that is "zero" degrees), and when prompted for "Select internal point" pick inside the walls on both sides of the door. Then <RET>. Then "Preview ". Then <RET>.
  7. Set the current layer to the "A-ANNO-DIM" layer. This is the layer on which dimensions should be drawn.
  8. Fully dimension the interior dimensions of the room, using the semi-automatic dimensioning feature of AutoCAD. To dimension the horizontal lines select from the Pull-down menu "Dimension" then "Linear" then OSNAP to the left-most point you want to dimension from (the "First extension line origin"), and then OSNAP to the right most point you want to dimension to (the "Second extension line origin"). Then pick a point through which you want the dimension line to pass. The vertical dimensions work the same: use the "Dimension" then "Linear" sequence from the Pull-down menu. The dimension of the diagonal wall also works the same, but use the "Dimension" then "Aligned" sequence from the Pull-down menu, and OSNAP to the endpoints of the diagonal line.
  9. To do two dimensions continued in a string, first draw the first dimension the usual way, then select "Dimension" then "Continue" from the Pull-down menu. Pick the next origin point to dimension to. AutoCAD will assume that the First extension line origin for that continued dimension is the second extension line origin from the previous dimension.
  10. Note that all dimensions are associated with their objects that are dimensioned. When those objects change length by stretching or scaling, the dimensions will be recalculated automatically and the dimension numbers will be redrawn. Note that you should always dimension in Model Space, since you are making the dimensions "associate" to a full sized object.
  11. Dimension the angle of the wall. Draw a horizontal base line from which the 45 degree angle can be measured. To dimension the angle select from the Pull-down menu "Dimension" then "Angular" then pick the line you just drew, and then pick the diagonal wall. Select a point through which the dimension arc will pass.
  12. Dimension the radius of the table. If ORTHO is turned on, be sure it is off before you do this step. To dimension the radius, select from the Pull-down menu "Dimension" then "Radius." Pick the circular table of which you want to dimension the radius The circle should be picked at the upper-right side of the circle to get the radial dimension to be drawn as shown on the attached drawing. Now apply a "center mark" (a pair of short crossed lines) to the circle also to make the dimensioning complete. To do this, select from the Pull-down menu "Dimension" then "Center Mark," then pick the circle anywhere on its locus.
  13. Thaw all layers. To do this quickly, type -LA <RET> T <RET> * <RET> <RET>. Then type REGEN <RET>.
  14. Enter Paper Space - select the Layout tab.
  15. In Paper Space, using DTEXT: command with 1/4" high lettering, make the title "DIMENSIONS" below the plan of the room
  16. Put a main sheet title at the bottom of the drawing containing your name, the course number, the date, and the instructor's name.
  17. Switch to floating model space.  Zoom to extents and then zoom 1/48xp.
  18. Switch back to paper space.
  19. Save the drawing: Click on the "Save" icon on the Toolbar (the one that looks like a floppy disk). Since you originally gave this drawing a name when you first created it, it will be automatically saved to that same name when you pick the "Save" button without any further input from you. (AutoCAD calls this process a "Quick Save.").
  20. Plot the drawing using the HP 5si printer. Plot the drawing in Paper Space at a scale of 1=1. Select the "Plot" icon from the Toolbar. Set plotter parameters.
  21. When plotting is finished, if you are satisfied that everything is OK, close (exit) AutoCAD, by clicking on the X in the upper right corner of its window. You will now be back on the Windows desktop.
  22. Copy the drawing to your own USB flash disk.