Auto Cad q Third Class

7/29/2019 Auto Cad q Third Class

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Republic of Iraq Class: Third

Ministry of Higher Education and

Scientific Research

Subject: AutoCAD

University of Technology

Examiner:

Dr. Laith Abdullah Mohammed

Q1: Using the appropriate Geometric Modeling technique, Define, in detail, the following model:

Q2: Construct the following model using 3D geometry commands.

Q3: Using one closed polyline, draw the two shafts shown below.


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Q4: Create the composite machine support model using geometric modeling techniques.

Q5: Using 2D closed REGION shape to construct the splined shaft.

Q6: Create the assembled model shown in figure below using solid blocks.


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Practical assignments:

Q7: Figure below shows the isometric view of a Tool Holder. Draw in first angle projection the

following views:

A plan view, showing all hidden detail, looking in the direction of arrow P.

A front view, showing all hidden detail, looking in the direction of arrow F.

A sectional plan view on cutting plane A-A.

Include 10 main dimensions on your drawing, 5 on each view.

Q8: Figure below shows the dimensions of a Microphone including all hidden detail.

Create an accurate solid model of the Microphone using AutoCAD solid modeling

commands. Display the completed solid model in an Isometric orientation with appropriate

shading.

Calculate the weight of the Microphone using AutoCAD commands to within two decimal

places. Insert your answer as a note beside the model. Assume the Microphone is completely

from made from PTFE (Polytetrafluoroethylene) plastic which has a density of: 2300kg/m3


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Q9: Replicate the following symbols as shown in Figure below, in AutoCAD and insert a Note

explaining what each symbol means.

Q10: Identify the following common Engineering Features listed A to E in Figure below.


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Answers:Q1:

1. With MVLAY1 tab, layer MODEL and UCS BASE current, zoom centre about the point 70,40,25 at 150

magnification in all viewports

2. Create the model base from lines and trimmed circles using the sizes given in fig(a). Use the (0,0) start point

indicated.

3. Make a new layer RULSRF, colour blue and current

4. Set the SURFTAB1 system variable to 18

5. Using the ruled surface icon (three times) from the Surfaces toolbar, select the following defining curves:

a) lines 1 and 2

b) arcs a and b

c) lines v and w

d) effect as fig(b)

6. Erase the ruled surface and create the top surface of the model by copying the base objects:a) from the point 0,0,0

b) by @0,0,50 fig(c)

7. With layer RULSRF still current, select the ruled surface icon and select the following defining curves as fig(c):

a) lines 1 and 2 ruled surface added

b) lines 3 and 1 no ruled surface added and following message displayed:

Object not usable to define ruled surface why?

c) Explanation: when the second set of defined curves was being selected:

1. point 3 was picked satisfactorily

2. point 1 could not be picked you were picking the previous ruled surface added between lines 1 and 2

d) cancel the ruled surface command (ESC) and erase the added ruled surface

8. Make the following four new layers:

R1 red; R2 blue; R3 green; R4 magenta

9.a

) Make layer R1 currentb) Add a ruled surface to the base of the model (three needed)

10. a) Make layer R2 current

b) Freeze layer R1

c) Add a ruled surface to the three outside vertical planes of the model

d) Thaw layer R1 fig(d)

11. a) Make layer R3 current

b) Freeze layers R1 and R2

c) Rule surface the top three defining curves of the model

12. a) Make layer R4 current and freeze layer R3


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b) Add a ruled surface to the three inside vertical planes

13. a) Thaw layers R1, R2 and R3

b) Model displayed a fig(e)

14. Menu bar with View-Hide to give fig(f)

15. Menu bar with View-Shade-Gouraud Shaded

Q2:

1. Select the BOX icon from the Surfaces toolbar and:a) corner: 0,0,0b) length: 100; width: 100; height: 40; Z rotation: 0c) colour: red2. Select the WEDGE icon from the Surfaces toolbar and:a) corner: 0,0,40b) length: 30; width: 30; height: 30; Z rotation: 0

c) colour: blue3. Zoom to a scale factor of 14. The two 3D objects will be displayed as fig(a)

Rotate the wedge:

1. From the menu bar selectModify-3D Operation-Rotate 3Dand:promptSel ect obj ect srespondpick the blue wedge then right-clickpromptSpeci f y f i r st poi nt on axi s or def i ne axi s by [ Obj ect /Last / . .enterX the X axis optionpromptSpeci f y a poi nt on t he X axi s

enter0,0,40 why these coordinates?promptSpeci f y r ot at i on angl eenter90 2. The blue wedge is rotated about the x-axis as Fig. 22.1(b)

3. Activate the Rotate 3D command and:promptSel ect obj ect senterpick the blue wedge the right-clickpromptRot at e 3D opt i ons


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enterZ the Z axis optionpromptSpeci f y a poi nt on Z axi senter0,0,0 promptSpeci f y r ot at i on angl eenter90 4. The blue wedge is now aligned as required fig(c)

5. Select the ARRAY icon from the Modify toolbar and with the Array dialogue box select:a) Type: Polar Arrayb) Objects: the blue wedgec) Center point: X: 50 and Y: 50d) Method: Total number of items & Angle to fille) Total items: 4f) Angle to fill: 360g) Rotate items as copied: active6. The blue wedge is arrayed to the four corners of the box as fig(d)7. With the Rotate 3D command:a) pick wedges 1 and 2 then right-clickb) enter Y as the defined axisc) enter 100,0,40 as a point on axis why this entry?d) enter 90 as the rotation angle

8. Now move these two rotated wedges from 0,0 by @30,09. The final result is fig(e).

Q3:

1. Draw aclosedpolyline outline using the sizes given. Use the (0,30) start point.2. Set ISOLINES to 123. Menu bar withDraw-Solids-Revolveand:promptSel ect obj ect srespondpick the polyline then right-clickpromptSpeci f y st ar t poi nt of axi s of r evol ut i on or def i ne axi sby [ Obj ect/ X ( axi s) / Y ( axi s) ]enterX the X axis optionpromptSpeci f y angl e of r evol ut i onenter360 4. The polyline outline will be revolved about the X axis as fig(a)

5. Select the revolve icon from the solids toolbar and:a) objects: select the polyline outline then right-clickb) axis of revolution: X axisc) angle of revolution: 250d) the revolved effect will be as fig(b). Observe then undo6. At the command line enter REVOLVE and:a) objects: select polyline then right-clickb) axis of revolution: enter Y c) angle of revolution: 360d) the result will be as fig(c) pan needed?


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e) observe then undo the revolved effect7. Finally revolve the polyline:a) about the Y axisb) with a 300 angle of revolution fig(d)

Q4:

1. With the 3D viewport active, use the BOX icon to create two primitives as fig(a) with:a) corner: 0,0,0b) corner: 100,120,25

length: 100 length: 100width: 150 width: 90height: 25 height: 60colour: red colour: blue2. Create a cylinder on top of the blue box with:a) centre: 50,30,85b) radius: 50c) height/other end: enter C then@0,90,0 d) colour: green


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3. Create a wedge with:a) corner: 0,120,85b) length: 70; width: 100; height: 70c) colour: magenta4. Rotate (2D rotate) the magenta wedge:a) about the point: 0,120,85b) by: 90 degrees to give fig(b)5. Select the INTERSECTION icon from the Solids Editing toolbar and:promptSel ect obj ect srespondpick the green cylinder and magenta wedge then right-click6. Select the UNION icon from the Solids Editing toolbar and:promptSel ect obj ect srespondpick the red and blue boxes and the intersected wedge/cylinder thenright-click7. The model now appears as fig(c)8. Refer to fig(c) and menu bar withTools-New UCS-3 Pointand set a new UCS with:a) origin: MIDpoint icon and pick line 12b) X axis: ENDpoint icon and pick pt2c) Y axis: QUADrant icon and pick pt3 on curve9. The UCS icon will move and align itself on the sloped surface

10. Save this UCS position as SLOPE11. Create a cylinder with:a) centre: 0,35,0b) radius: 18c) height: 100d) colour: number 54 use the CHPROP command12. Select the SUBTRACT icon from the Solids Editing toolbar and:promptSel ect sol i ds and r egi ons t o subt r act f r om. .Sel ect obj ect srespondpick the composite model then right-clickpromptSel ect sol i ds or r egi ons t o subt r actSel ect obj ect srespondpick the cylinder then right-click fig(d)13. Restore UCS BASE14. Create a cylinder with:a) centre: 20,15,0b) radius: 9c) height: 25d) colour: number 17415. Multiple copy the cylinder:a) from: 20,15b) by: @60,0 and by: @30,12016. Using the SUBTRACT icon:a) select the original composite then right-clickb) pick the three cylinders then right-click

17. The model is now complete and is displayed in fig(e) without hide and in fig(f) with hide.18. Select the Model tab and Gouraud shade the model, then use the 3D orbit command to rotate the shaded model19. Restore the model to 2D wireframe representation.


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Q5:

1. Create the layout from three circles having diameters 120, 40 and 16. The actual layout is your design but use the

0,0 point as indicated.2. Select the SUBTRACTION icon from the Solids Editing toolbar, pick the largest circle then right-click and:promptNo sol i ds or r egi ons sel ect ed3. Select the REGION icon from the Draw toolbar and:promptSel ect obj ect srespondpick all circles then right-clickprompt13 l oops ext r act ed13 Regi ons cr eat ed

4. Menu bar withModify-Solids Editing-Subtract and:promptSel ect sol i ds or r egi ons t o subt r act f r omSel ect obj ect srespondpick the largest circle then right-clickpromptSel ect sol i ds or r egi ons t o subt r actSel ect obj ect srespondpick the 12 smaller circles then right-clickandthe region is created as fig(a)5. With the lower left viewport active select the EXTRUDE icon from the Solids toolbar and:a) objects: pick the regionb) height: 100

c) taper angle: 0d) hide and shade


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Q6:

1 Make a new layer TRAY, colour blue and current2 With UCS BASE, create two primitives from:Box Cylindercorner: 0,0,0 centre: 10,0,0length: 110 radius: 10width: 80 height: 40height: 402 Rectangular array the cylinder:a) for 2 rows and 2 columnsb) row distance: 80 and column distance: 703 Union the box and the four cylinders fig(a)4 Create another two primitives from:

Box Wedgecorner: 10,10,10 corner: 110,0,40length: 110 length: 15width: 60 width: 80height: 40 height: 405 Subtract the box and wedge from the composite fig(b)6 Draw a polygon with:a) sides: 5b) centre: 10,0,0c) inscribed in a circle of radius 57 Solid extrude the polygon for a height of 10 with 0 taper8 Menu bar withModify-3D Operation-3D Arrayand:promptSel ect obj ect s

enterL two returns for the cylinder (last object)promptEnt er t he type of ar r ay and enter: R promptEnt er t he number of r ows and enter: 2 promptEnt er t he number of col umns and enter: 2 promptEnt er t he number of l evel s and enter: 2 promptSpeci f y the di st ance between r ows and enter: 80 promptSpeci f y t he di st ance between col umns and enter: 70 promptSpeci f y t he di st ance bet ween l evel s and enter: 30 9 Subtract the eight cylinders from the composite fig(c). A paper space zoom may be


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needed to help with this, but remember to return to model space10 At the command line enterBLOCK and:promptEnt er bl ock name and enter: TRAY promptSpeci f y i nser t i on base poi nt and enter: 0,0,0 promptSel ect obj ect srespondpick the composite then right-click11 The tray block may disappear. If it does not, erase it12 The -BLOCK entry allows the prompts to be entered from the keyboard and not fromthe dialogue box

The support1 Make a new layer SUPPORT, colour magenta and current2 Draw two polygons then solid extrude using the following:polygon 1 polygon 2a) sides: 6 6b) centre: 0,0,0 50,50,0c) inscribed: rad 5 rad 5d) height: 130 140e) taper: 0 0

3 Change the colour of the 140 high cylinder to green4 The two extrusions are displayed as fig(d)5 Make two blocks of these supports with:a) Name: SUP1Insertion base point: 0,0,0Objects: pick the red extrusion and b) Name: SUP2Insertion base point: 50,50,0Objects: pick the green cylinder and

Inserting the blocks1 Zoom extents the zoom 1.2 in all viewports2 Make layer TRAY current3 Menu bar with Insert-Block and:promptI nser t di al ogue boxrespond1. At Name scroll and pick TRAY2. ensure the on-screen prompts are active (tick)3. pick OKpromptSpeci f y i nser t i on poi nt and enter: 0,0,0 promptEnt er X scal e f act or and enter: 1 promptEnt er Y scal e f act or and enter: 1 promptSpeci f y r ot at i on angl e and enter: 0 4 Repeat the INSERT command and insert block TRAY:a) at the point 0,0,150b) full size (i.e. X=Y=1) with 0 rotation5 At the command line enter-INSERT and:promptEnt er bl ock name and enter: SUP2 promptSpeci f y i nser t i on poi nt and enter: 10,0,30 promptEnt er X scal e f act or and enter: 1 promptEnt er Y scal e f act or and enter: 1 promptSpeci f y r ot at i on angl e and enter: 0 6 Menu bar withModify-Solids Editing-Unionand:promptSel ect obj ect srespondpick the three inserted blocks then right-clickpromptAt l east 2 sol i ds or copl aner r egi ons must be sel ect ed7 What does this prompt mean? The union operation has not been successful with the


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three inserted blocks. This is because blocks must be exploded before they can be used with Boolean operations.8 Using the EXPLODE icon from the Modify toolbar, select the three inserted blocks.

Checking for interference1 Make layer 0 current2 Menu bar withDraw-Solids-Interferenceand:promptSel ect t he f i rst set of sol i dsSel ect obj ect srespondpick the top tray then right-clickpromptSel ect t he second set of sol i dsSel ect obj ect srespondpick the support then right-clickpromptCompar i ng 1 sol i d agai nst 1 sol i dI nt er f er i ng sol i ds ( f i r s t set ) : 1( second set ) : 1I nt er f er i ng pai rs : 1Cr eat e i nt er f erence sol i ds>[ Yes/ No]enterY 3 The model will be displayed with a black solid (layer 0) where interference occurs between the tray and thesupport leg. This interference is due to the support leg (SUP2) being too long, or the TRAY having been insertedinto the drawing at the wrong insertion point. We deliberately created the support leg (SUP2) with a height of 140 toobtain interference.4 Erase the support leg and the black interference cylinder will still be displayed. Erase this interference cylinder.

Inserting the correct support1 Still with the two (exploded) inserted trays displayed?2 UCS BASE, lower left viewport active and layer SUPPORT current3 INSERT the support block SUP1 with:a) insertion point: 10,0,30b) full size with 0 rotationc) explode this inserted block4 Rectangular array the inserted support:

a) for 2 rows and 2 columnsb) row distance: 80 and column distance: 705 Make layer MODEL current6 Menu bar withModify-Solids Editing-Unionand pick the six exploded blocks then right-click fig(e)7 The composite will be displayed blue or magenta. Why is this when layer MODEL (red) is current? The colour ofthe composite depends on the order you selected for the union operation. If a tray was the first object selected, thenthe composite will be blue, and if a support was first selected, then the composite will be magenta.8 Using the CHPROP command, pick the composite and change the layer to MODEL. The composite should bedisplayed in red.

Completing the model1 Create a cylinder with:a) centre: 150,40,0

b) radius: 50 and height: 2002 Subtract this cylinder from the composite fig(f)

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Auto Cad q Third Class