Drawing (Detailing)

Mechanical drawing is an essential part of CAD modeling

because it is the two-dimensional substitute of three-

dimensional model on a paper (i.e., in two-dimensional

space).

Engineering Drawing is also called mechanical drawing,

production drawing, or multiview drawing. It contains

necessary views of the model to describe the product

completely with dimensions, notes, sections, and bill of

materials. Also, it includes a title box that may contain part

name, drawer, inspector, company name, part number, and

scale.

PROJECTION

General

Projection

Details

Auxiliary

Revolved

VISIBLE AREA

Full

Half

Partial

Broken

SECTION

Full

Half

Local

Aligned

Types of Views

1. Create a Drawing File

• File > New > Drawing > type in “shaft-support-2” as model as

shown below

• Click “Empty with Format” and select “a.frm” that is close to A4

size typewriter paper. Try other forms for differences. The

empty A-frame drawing file is opened.

Drawing Window

• Layout > General

• OK (for No Combined State)

• Pick a point at near upper right corner on the graphics window

(GW) to place a 3D view

• Drawing View dialog appears. Change Default orientation to

Isometric > OK. User can double click the view to bring it

back.

2. Add a View

• General > check “Do not prompt” > OK

• Pick a point for front view

• Default orientation = User Defined > pick FRONT for Model

view names > Apply

• Scale > Custom Scale > enter a proper value > Apply (to see

the change and repeat) > Close

3. Add More Views

• While the front view is being selected, Model Views/Projection

> place the top view > pick the front view again > Projection >

place the right side view

• Change to Hidden Line for Display Style and turn off DP’s and

CS > zoom in and out by scroll button to refresh GW. It now

appears as

• Unselect Lock View Movement > pick a view and then move

the mouse over to see the move cursor. Move the view

holding down the mouse. The note for scale can be moved

too. The drawing may appear now as

4. Move Views

There are shortcut menus that can be accessed by right clicking

the mouse.

• The first short cut menu pops up when the mouse is over a

view and right clicked,

• the second after a view is clicked (selected) and then right

clicked, and

• the third one pops up when the mouse is right clicked over a

position in the drawing other than view areas.

• The last one appears when Drawing Models menu is clicked.

When done, click Done/Return.

Shortcut Menus

Annotate tab

• Click Show Model Annotations menu to bring up the dialog

below.

5. Show Dimensions

• Click a view to display dimensions and bring up all dimensions

in the dialog. Alternatively, pick a feature one by one.

• Check dimensions to keep in the dialog or in the drawing >

Apply (finish the current view)

• Repeat this for all other views.

• User can preselect a view first and then Show Model

Annotations.

Moving Items from One View to Other View

• Items like dimensions on the drawing can be move to other

views. Pick an item > right click > Move item to View > pick a

new view. Try moving the small hole diameter in top view to

front view.

Drawing

Dimension - New References

Alternatively, the dimensions can be added one by one.

1. Entity > pick on an entity > middle click to place the dimension

2. You may pick two entities to place dimension between them.

3. For dimensioning between circular entity and others, use

Center. Use other menus below in similar ways.

• The dimensions can be rearranged

by Clean Dimensions > pick a view

> pick dimensions > OK

• Apply in the Clean Dimensions

dialog

• Change the Offset and Increment if

the result is not satisfactory by

[click Select in the dialog > pick

the view > OK > Apply > Close].

• Snap Lines may still appear as

shown above. Move the mouse

around to highlight them and pick >

delete them by Delete key if

necessary.

6. Clean Dimensions

1. Line up dimensions in the figure above by [pick the dimension

20 > ctrl + pick another dimension 50 > click Line Up

Dimensions ]. Repeat this for other dimensions as needed.

2. More options for dimension can be found. Double click the

diameter dimension to bring up Dimension Properties dialog

as below > click the button Flip Arrows > click Move and move

the selected dimension (this can be done simply on the

window by clicking the dimension and hold-moving it) > also

click other tabs, Dimension Text and Text Style, to see more

options.

7. Line Up Dimensions and Dimension

Properties

• Create a new dimension from a small hole to larger hole by

[click Dimension > Center > pick both holes on the

circumference > click MMB at the desired place for dimension

> Horizontal > Return

• Delete the unnecessary dimension 70 by [pick the dimension

> RMB (hold down) > Erase > click any point in the window].

• Now, line up two dimensions 15 and 55 as before. Now, the

dimensions may appear as

8. Create and Erase Dimensions

• Note that any dimensions can be moved to another view by

[pick the dimension > RMB (hold down) > Move Item to View >

pick another view]

Annotate tab

• Add Note > No Leader / Enter / Horizontal / Standard / Default

> Make Note > pick a position in the drawing > in Note

Properties dialog, enter the text > Done > Done (to finish). Text

Symbol can be used.

• To modify a note, double click it to bring up Note Properties

dialog below > edit the note > Text Style tab > change font,

size, and color > OK

• Drop down Annotations > Balloon Note > With Leader/other

default options > Make Note > click an edge belonging to the

feature for note > MMB at position to place > enter the note >

MMB (CR) > MMB (finish)

• MMB to continue with another note

9. Add Note

• Show Model Annotations

• Click Model Datum tab as below

• Pick a view > check datums to keep in dialog or in drawing >

MMB or Apply (finish the current view)

• Repeat this with other views.

• In the following drawing, the datum axis was added in all

views.

10. Show Model Datums

- Drawing

• Start a new drawing

• Add the front view with a scale.

Repeat to add the top and right-side

views.

• Annotate tab > Model Datum /

Model Datum Plane > enter a name,

select Display and Define

11. Datum Planes

• Define the datum plane (ex., through an axis and

perpendicular to a plane in edge view)

• DP can be deleted only in the part (not in drawing).

Alternatively, the current DP’s can be used. Pick FDP in the top

view > RMB > Properties > change Name to ‘A’ and select

Type as shown below > OK

• Modify some options

for the current drawing

by File > Prepare >

Drawing Properties >

Detail Options >

Change.

• Other options may be

changed like

drawing_text_height,

dim_text_gap, and

gtol_datums.

12. Changing Options for Drawing File

• The Part file also

has options [File >

Options >

Configuration

Editor]

• Add tol_display and

set the value to yes

or no to display the

tolerances or not.

• Note that to display

tolerances,

tol_display of

drawing file option

must be first set

yes.

- Changing Options for Part File

13. Tolerances and Surface Finishes

First, change the display option for tolerances.

To change the types of tolerance dimensions, double click the

dimension to bring up the dialog and select the type.

Surface Finish symbol can be inserted by [Insert > Surface Finish

> Retrieve > Generic > Open > Standard > Open > Entity >

Normal > pick an edge for surface > enter a surface finish in

micro inches]

Geometric tolerances are used to control the form and/or location

of geometric features. In the following illustration a position

tolerance is introduced.

1. Insert > Geometric Tolerance

2. Click Position Tolerance > Select Axis for Type in Reference

To Be Selected > click Select Entity > pick on the axis of the

hole on the right in the top view > select Dimension in

Placement To Be Placed > pick on the diameter dimension (to

which the geometric tolerance symbol will be attached)

14. Geometric Tolerances

3. Click the tab Datum Refs > click Primary > click Select for

Basic > pick the datum plane A in the view > repeat this for

Secondary and select the datum C > repeat for Tertiary and

select the datum B.

4. Click the tab Tol Value > enter 0.002 for Overall Tolerance >

select MMC for Material Condition

Help: MMC (Maximum Material Condition) is one of three terms

used to specify the limits of size of a part when applying

geometric tolerances. The other two terms are LMC (Least

Material Condition) and RFS (Regardless of Feature Size).

For example, a shaft is at MMC when it has the largest

diameter and a hole is at MMC when the diameter is smallest.

RFS indicates the tolerances apply to a geometric feature

regardless of the size and it may range from LMC to MMC.

5. Click the tab Symbols > check Diameter Symbol

6. Ok (close the dialog). The final drawing may appear as

- Removing Annotations

Annotations including tables can be erased or deleted.

• Select correct ribbon like Annotate for dimensions or

Table for tables, then right click the annotation in DT

(drawing tree) > Delete or Erase

15. Tables and Hole Tables

Tables are used to collectively show non-

graphical data in drawings. One of

uses is BOM (bill of materials).

Another is component list in

assembly file.

• Table tab > Table > select the size >

pick a position to place in DW (drawing

window).

• Add Column/Row > click a inside table

line to add to next .

To create a hole table, let’s convert one of the smaller holes into

UNC threaded hole. In part file, Edit Definition > fill in as

below > Done

Hole Table

Hole Table requires a coordinate system with x-y axes aligned

with hole placement surface. Create a local coordinate

system at the front left corner as shown below.

Back in drawing file, Hole Table > Create > Hole > select the local

coordinate system in the view that shows the hole placement

surface (i.e., x-y axes) > select a position for top left corner of

the hole table > Done (see the previous slide that has both

table and hole table)

16. Section View

First create the section on the model by [View > Manage Views >

View Manager > Sectons tab].

Using Previously Created Section in the Model

1. New > enter a name > CR

2. Choose options like Planar or Offset (for angular or linear) /

Single > Done

3. For Single, pick a plane.

4. For Offset, pick a plane for SP > MMB

5. Pick References if not completely placed > Close

6. Sketch an offset cutting line > OK (sketch)

7. Select the Clipping direction > Done (section)

7. Options > Show Section

8. Close (view manager).

Creating New Section in the Drawing

A. Full Aligned Xsec

1. Add views first

2. Double click the view for section

3. Sections > 2D Cross Section

4. The sections created before appear. New sections can be

also created. Select the section B created before in the model

5. Choose Full for Sectioned Area > Apply

6. The section view appears as below. No good practice !!

7. Back in Drawing View dialog as below, Full(Aligned) > pick

the axis of rotation > OK

The section appears correctly as below.

1. Double click the top view (to bring up the view dialog)

2. Sections > 2D Cross Section

3. [+] > Create New

4. Offset / Both Sides / Single > Done

5. Enter the section name > CR

6. Now, user is given 3D model in another window > select the top of

the plate for the sketch plane > Okay > choose Bottom and pick the

front face as the sketch reference plane

7. Sketch lines as below (make sure to cut through the part)

8. Alternatively, Coincident can be used between the datum axis (rotate

to see it) and the line

9. OK (Sketch)

B. Full Offset Xsec

8. Back in Drawing View dialog, Apply to see. Close it.

- Adding Cutting Line Arrows

C. Partial Xsec

1. Add View > View Type: Projection / Full View / Section / No

Scale > Done

2. Xsec Type: Local / Total Xsec > Done

3. Pick a position in the drawing to the right of the top view

4. Add Breakout / Show Outer / Choose Xsec > Create > Planar

/ Single > Done

5. Enter a section name > CR

6. Pick on the vertical datum plane RIGHT that runs through the

center of the cylinder > pick on the top view to be sectioned >

pick a position for center of the view on the section view (see

below) > (do not click Spline tool) > sketch an open spline

around the center point > click MMB (to finish) > Done > Done

7. To bring back the menu manager, pick a view and use RMB

to select Properties > Boundary

8. Now, use any of the menus; Mod Breakout (pick the outline >

draw a new spline), Add Breakout, Del Breakout, Move Ref

Pnt (move the reference point like section center point),

Show Outer, and Erase Outer.

D. Half Section View

Everything is same as the steps in full section except the

following.

1. Select Half View for section type

2. Pick a reference plane (bold line in top view below) that

divides the section into two sections and then select the side

shown by arrow (in section view below) by Flip if necessary.

E. Revolved Section View

1. As in the previous sections, add front and top views.

2. Add View > View Type: Revolved / Full View / Section / No

Scale > Done

3. Pick a center point on the front view where the revolved

section is to be placed

4. Click the front view as the parent view

5. Create > Planar/Single > Done > Enter a section name > CR

6. Pick on the RIGHT datum plane that runs through the center

of the part (You may create a datum plane if needed here)

F. Broken Section View

This view is used to remove part of the section in the middle for

sectioning of long or large model. The procedure is same

except the specification of two vertical and/or horizontal lines

to remove middle portion.

Note that if the view type is Projection, the view cannot be created

in the direction that shows up full in the parent view.

Otherwise, an error message appears as “Number of

vertical/horizontal break lines must be 0”.

1. Add View > View Type: General / Broken View / No Xsec /

Scale > Done

2. Pick a center point in the drawing where the section is to be

placed

3. Enter a scale > CR

4. Orientation dialog appears. Click FRONT for the front view >

click TOP for top view > OK (close the dialog)

5. Add/Vertical > click two points on the view to select reference

points to add break lines (see below)

6. Done. The two broken portions appear in joined form (see the

second figure above)

7. Pick the line at the joint of both pieces which share spline

sketch and direction

8. OK (do not click Done)

9. Sketch (already selected) > sketch the broken line in the view

(it’s a spline) > once done, click middle mouse button > OK >

Done

10. Add dimensions using Show/Erase dialog for features one by

one > Accept All > Close

11. The dimension can be created between two centers. Click

Dimension menu in the tool bar > Center > pick two circular

arcs one each on both sides > click middle mouse button to

finish where the dimension to appear > Horizontal (for

dimension orientation) > OK

12. Moving Broken Subviews. The broken subviews can be

moved individually except the upper left view which can be

used to move all broken subviews together.