NX 8.5 Model Tutorial Construction of 1B-1
Launch NX
All Programs > Course Software > Retired > NX8.5
Start a new file
File > New
Make sure to set UNITS
Name your file
Set “Folder” to point to
your home directory
(I:\ drive)
Pick the “folder” icon and
then use the Windows
dialogue to find your
home directory.
Set your ROLE
Roles > Advanced with Full Menus
Before we start we are going to set some software Preferences
This link opens a handout on Preferences Settings for NX. They need only be set once for a file, but they will need to be set for each
file you create. Get in the habit of setting them first.
NX Preferences
Next we will begin construction of the model geometry.
Insert > Design Feature > Extrude
(or find the “Extrude” icon in the icon menu)
The EXTRUDE dialogue will open and Section – Select
Curve option will be highlighted. This is prompting the
user to select the location and orientation of the sketch
plane for the 2D profile which will then be extruded.
Move to the construction screen and select the XZ plane
the global coordinate system as shown in the next
window.
of
HERE IS A TIP:
Selection of the
section plane is
important in that it will
define the “default”
orientation of the
object for display and
can also simply the
construction of
assemblies. Make
this choice carefully.
The SKETCH dialogue will open next and is shown below. This dialogue will provide command for the creation of the 2D profile which
will define our extruded shape. Note that the PROFILE option is preselected. The parts of the dialogue are specified in the figure.
Commands for creating and editing lines. Selected
command is in white.
Commands for constraining the geometry
either dimensionally or geometrically.
Options for geometry selection e.g. endpoint of line, center of arc,
intersection, quadrant point, etc.
Next we will draw the first feature profile:
We started at the lower left corner and
selected a point then moved upward. The line
will “snap” to vertical and then we can select
the next point. Notice that there exist drawing
aids that will help you to know when, for
example, lines are perpendicular and points
are aligned.
Complete the sketch of a rectangle by
connecting to the start point and then end the
process by pressing the MMB (middle mouse
button)
HERE IS ARE SOME TIPS
If you want to UNDO the last input, go to EDIT
> UNDO at the top of the screen
To ‘Unselect” something, use SHIFT-PICK
The rectangle at the midpoints of the lines are indicators of geometric constraint. These particular symbols indicate that the lines are
Horizontal or Vertical with respect to the coordinate system of the sketch plane.
Next we will add dimensional constraints to the sketch. To create a dimensional constraint,
Go to the sketch menu bar and select the Dimension icon
The default selection method for the command is “Inferred” (this is indicated
by the lightning bolt). Inferred means that the software will attempt to
interpret the type of dimension desired (linear, radial, diametric, etc.) based
upon the geometry selected.
To create a linear dimension (as shown at right), one can;
Pick the horizontal line and move the mouse. Use the LMB to place
the dimension. This option associates the dimension with endpoints
of the line.
Pick each of the vertical lines and then use the LMB to place the
dimension. This option associates the dimension with vertical lines
defining the length.
One can also combine options by picking a line and then an
endpoint.
It may be helpful to think of the dimension as a variable. When the
dimension is placed, two input panes are displayed, the left one is the name
associated with the variable, the right is the current value. Both can be
modified by highlighting and changing the value.
Set the value of the dimension to 3
Next use the same techniques to place the vertical
dimension as shown in the figure at right.
Set the value of this dimension to 2.25
This defines the “height” and “width” of our profile.
The next step is to locate the profile with the sketch
plane. For this we will use the coordinates shown on
screen as references.
Within the dimension command, pick the left hand vertical line and then the YC
axis. Place the dimension using the same technique as before.
This dimension locates the profile in the horizontal direction within the sketch
plane.
the
Create the vertical locating dimension by selecting the horizontal sketch line
and then the XC axis.
We are now going to use dimensions to center the sketch geometry within
the sketch plane.
In the “value” pane of the open dimension, enter a new dimension value of
the overall value divided by 2.
In our case that is:
p8 / 2
To repeat for the other locating dimension, double-click on the dimension
value to open the input panes of the dimension.
Set that value in the same fashion.
The sketch geometry will update dynamically.
To end dimension input press MMB
Note that the sketch geometry changes in color and the degree-of-freedom
indicators (the little arrows) have disappear. In the message window at the
top of the construction window the message will read “Sketch is Fully Constrained”
SOME TIPS:
To move an existing dimension, pick the dimension to highlight, then Pick-Hold-Drag
To delete a dimension:
Edit > Delete at the top of the screen OR pick to highlight then RMB and delete
If you should accidentally change your display (rotate orientation, zoom, etc.)
select the Orient View to Sketch icon in the Sketch Menu
We have completed the first sketch
and will now extrude the profile to
generate a solid.
Select Finish Sketch (the checkered
flag) at the top of the Sketch Menu
The Extrude dialogue will open
automatically and the view orientation
will change to the default (in this case
isometric).
The temporary extrude will be
displayed in a default direction. To
change the direction, pick the first
button in the Direction Panel. The
view will change dynamically.
To change the distance of the extrude
either enter a value in the End
Distance panel,
or pick the arrowhead of the extrusion
direction indicator on the view and
drag.
Set the Value (by whichever method)
to 1.0
Then select OK in the dialogue or press the MMB to complete the Extrude operation.
Next we will create additional features…
First the cut features on the front face.
Start the Extrude command as before (Insert > Extrude or Extrude Icon)
In the Selection option, select the front face of the existing solid as shown
at right.
From the construction commands in the Sketch menu pick the
Rectangle command.
Make sure that the Rectangle Method is set to the first option (Two Point)
This will define a rectangle by picking the opposite corners.
First pick the upper left corner of the existing face. This will anchor the
sketched rectangle to the corner.
Drag the other corner to an approximate location as shown. The exact
distance is not critical, we will provide a constraining value next.
Create dimensions for the sketch profile (the rectangle), using the methods
used on the original profile.
Set the width value to .25
Set the height to 1.125
Select Finish Sketch (the checkered flag)
HERE IS A TIP: Remember in the first profile we centered the profile by
enter an equation for the dimension value. This means we can also
enter a fraction value. For example, if you were working from the 1B-1
homework sheet and noted that the height of the profile was 9 squares
and each square is 1/8 inch, we could enter a dimension value in the
input pane of 9/8 rather than 1.125.
we
Next is the Extrusion phase…
This will be a cut feature but the software
default is to an added feature.
First we need to change the extrusion direction.
Press the first toggle in the Specify Vector
panel.
Next we set the distance for the extrusion.
Leave the Start value at zero (0)
Set the End value to 0.5
Note that the Inferred Boolean is automatically set
to (Subtract) since there is material interference.
OK or MMB to create the cut feature
We will now create the other cut feature on the opposite side of the component.
Select the Extrude Command and then select the same face as for the previous cut
feature.
Once again we will use the Rectangle Command to create the profile.
This time we will start in the lower right hand corner of the face and pick an
opposite corner.
Dimension in the same fashion as the previous feature, and alter the
dimension values.
Reverse the direction of the extrusion.
Set the value for the extrusion distance.
Press OK or MMB to create the cut feature.
Next we will create the protrusion feature from the top face of the object.
Select the Extrusion command.
Select as the sketch plane the top face of the object (as shown)
NOTE: If your view of the surface is not complete use the following command;
Move the pointer to an emply portion of the model window.
Press the RMB to open the Display Quick Menu
Select FIT
Before we create the next profile we are going to set an option to make the
construction easier.
Select the indicated ICON which will
Allow Selection of Hidden Wireframe
This will allow us to select hidden features in the shaded view.
Now we will construct the profile using the Rectangle command again.
First place the upper left corner of the rectangle at the
corner of the top face as shown in the figure.
For the next point we want the upper right hand corner of the hidden cut
feature.
Choosing these two features to anchor the profile means we do not
need to dimension it’s size and also ties the size of the profile to the two
cut features in the case of future edits.
End the Sketch construction by choosing Finish Sketch (the checkered flag)
Set the Extrude distance to 0.5 in the direction shown.
Select OK or press MMB to create the extrude.
Next we are going to create the cut feature at the back and bottom of the
object. In order to create this feature we will need to change our view
orientation.
To change view orientation dynamically;
Move the moise to the approximate center of the display
Press and HOLD the MMB
Move the mouse to change the viewing orientation
Select the Extrude command again and when selecting the sketch plane
move to the coordinate icon and select the XZ plane of the coordinate axis.
The orientation will reverse so you will need to reorient the part.
We are going to create this profile in a pictorial view.
Use the Rectangle command again to define the profile. Place one corner on the
bottom edge of the object and place the other corner at an approximate location.
Create dimensions controling the height and width of the rectangle. Set the
appropriate dimension values.
Create a dimension which locate the sketch horizontally from the Z axis and set it’s
value equal to one half of the width of the profile.
Finish the Sketch
Note that the extrusion direction is already correct but that the inferred Boolean is set
to Unite. You will have to change it to Subtract before selecting OK
The component is now finished
This tutorial will provide you with the bare basics of model construction. Even within the
commands used, there are numerous options. You are encourage to examine the
command dialogue boxes and experiment with the commands to further understand the
inputs and their effects. For example, during the Extrusion, the effect of values
assigned to the “Start” and “End” options.
In a later tutorial we will examine other construction commands.