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AutoCAD exercise: an L bracket

Draw an L bracket in AutoCAD with relative coordinates: its outline, a fillet, two holes and baseline dimensions, solved step by step. Practise it free online.

Open in the editor

Draw this bracket, in millimetres: 100 long, a foot 20 high and an upright 30 wide and 80 high, the inside corner rounded to a radius of 10, a hole of 8 in the foot and one of 10 in the upright, each centred in its leg. The outline is one run of LINE, each point typed as how far it goes from the last, and its dimensions all start from the bottom left corner.

The drawing

The L bracket, 100 by 80, dimensioned from its bottom left corner.801006580R10Ø8Ø10
The L bracket, 100 by 80, dimensioned from its bottom left corner.

Step by step

The engine draws each step and writes its history as you would type it: the prompts in AutoCAD 2027's order, with the same option letters. After a command's first point, a typed point is measured from the last one, as dynamic input measures it, and the history writes it with @; # measures from the origin.

1. Draw the outline

On the Outline layer, LINE from 0,0, then each point as a step from the last: 100,0, 0,20, -70,0, 0,60 and -30,0. Close draws the last side back to the start and ends the command.

1. Draw the outline
  1. Command: LINE
  2. Specify first point: 0,0
  3. Specify next point or [Undo]: @100,0
  4. Specify next point or [Undo]: @0,20
  5. Specify next point or [Close/Undo]: @-70,0
  6. Specify next point or [Close/Undo]: @0,60
  7. Specify next point or [Close/Undo]: @-30,0
  8. Specify next point or [Close/Undo]: C
1. Draw the outline

2. Round the inside corner

FILLET: choose Radius, type 10, then pick the two lines that meet at the inside corner, the foot's top and the upright's side.

2. Round the inside corner
  1. Command: FILLET
  2. Current settings: Mode = TRIM, Radius = 0.00
  3. Select first object or [Undo/Polyline/Radius/Multiple]: R
  4. Specify fillet radius <0.00>: 10
  5. Select first object or [Undo/Polyline/Radius/Multiple]:
  6. Select second object or shift-select to apply corner or [Radius]:
2. Round the inside corner

3. Draw the holes

Two circles with CIRCLE, each by its Diameter: 8 at 80,10, in the foot, and 10 at 15,65, in the upright.

3. Draw the holes
  1. Command: CIRCLE
  2. Specify center point for circle or [3P/2P/Ttr (tan tan radius)]: 80,10
  3. Specify radius of circle or [Diameter]: D
  4. Specify diameter of circle: 8
  5. Command: CIRCLE
  6. Specify center point for circle or [3P/2P/Ttr (tan tan radius)]: 15,65
  7. Specify radius of circle or [Diameter] <4.00>: D
  8. Specify diameter of circle <8.00>: 10
3. Draw the holes

4. Dimension it

On Dimensions, DIMLINEAR from 0,0 to the foot's hole, 80,10, placed below: 80. DIMBASELINE goes on from the same first extension line: type the right end, #100,0, where # measures from the origin, then Enter twice to end it. The same up the left side, to the upper hole and then to the top, #0,80. DIMRADIUS on the fillet and DIMDIAMETER on each hole finish it.

4. Dimension it801006580R10Ø8Ø10
  1. Command: DIMLINEAR
  2. Specify first extension line origin or <select object>: 0,0
  3. Specify second extension line origin: @80,10
  4. Non-associative dimension created.
  5. Specify dimension line location or [Text/Angle/Horizontal/Vertical/Rotated]:
  6. Dimension text = 80
  7. Command: DIMBASELINE
  8. Specify second extension line origin or [Select/Undo] <Select>: #100,0
  9. Dimension text = 100
  10. Specify second extension line origin or [Select/Undo] <Select>:
  11. Select base dimension:
  12. Command: DIMLINEAR
  13. Specify first extension line origin or <select object>: 0,0
  14. Specify second extension line origin: @15,65
  15. Non-associative dimension created.
  16. Specify dimension line location or [Text/Angle/Horizontal/Vertical/Rotated]:
  17. Dimension text = 65
  18. Command: DIMBASELINE
  19. Specify second extension line origin or [Select/Undo] <Select>: #0,80
  20. Dimension text = 80
  21. Specify second extension line origin or [Select/Undo] <Select>:
  22. Select base dimension:
  23. Command: DIMRADIUS
  24. Select arc or circle:
  25. Dimension text = 10
  26. Specify dimension line location or [Text/Angle]:
  27. Command: DIMDIAMETER
  28. Select arc or circle:
  29. Dimension text = 8
  30. Specify dimension line location or [Text/Angle]:
  31. Command: DIMDIAMETER
  32. Select arc or circle:
  33. Dimension text = 10
  34. Specify dimension line location or [Text/Angle]:
4. Dimension it

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