The document describes the modeling and finite element analysis of a Ratch-N-Lock pliers project completed in NX 8.5 CAD software. Key steps included modeling each component of the pliers, including the link, locking block, sliding block, locking nob, jaw, handle, and jaw handle. The components were then assembled. A 10 pound force was applied to the handle in the finite element analysis to determine stresses on the pliers from an applied load.

1. John Benavides 1
John Benavides
EML 4535C
Summer 2015
CADCAM FINAL REPORT
CADCAM Midterm Section: Modeling a Ratch-N-Lock
Pliers
1. Project Goals
Every engineer should have at least some basic understanding of how a modeling program
operates. NX 8.5 is a common computer aided design (CAD) software, created by Siemens,
which engineers can use to create models, tools, and objects in. The goal of building a Ratch-N-
Lock Pliers from this class, is to learn the basic steps into designing and creating objects inside
this modeling program. For the final project using this Ratch-N-Lock Pliers, a finite element
model (FEM) was created after the modeling of the Ratch-N-Lock Pliers where complete. A 10
pound force was applied to handle section of the Pliers, and a piece of nylon was inserted into
the Jaw section to so that the force may be applied onto the nylon. This shall determine the load
forces on this object created.
2. Background/Description
Ratch-N-Lock Pliers is designed to both clam and lock onto a wide
array of object sizes. It is a combination of pliers, an adjustable
wrench, and a vise-grip. It can automatically adjust to any size nut,
bolt, or pipe with the adjustable sliding handle. The locking nob on
the back of the Pliers is meant to lock or unlock the Ratch-N-Lock
Pliers. This locking mechanism will cause the pliers to act like a
vise-grip where it can be used to pick up objects or hold the desired
object in place. Once the handles are squeezed together, the jaws of
the Ratch-N-Lock Pliers will lock around the object that is desired
and can then be used to loosen or tightened the object desired. The
shape and teeth of the jaw are designed to clamp and grip any size
bolt, nut, or fastener, this combined with the adjustable jaw position
makes this a multifunction tool.
Figure #1: Ratch-N-Lock Pliers

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Figure #2: Link Figure #3: Locking Block
Figure #4: Sliding Block Figure #5: Locking Nob
Figure #6: Jaw Figure #7: Handle
Figure #8: Jaw Handle

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3.1 Link
Step #1.1: Started a new sketch from XY plane datum, then create
the two latches/connection points to the handle and hole above with
respect to the XY datum.
Step #1.2: Created reference circles for teeth. Use
pattern curve to replicate teeth once one tooth is
created.
Step #1.3: Finished making body of the link with
the line tool, arc tool, and tangent constraints.

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Step #1.4: Extrusion the main body
symmetrically 1/16”. Extrude the out connection
point diameter symmetrically by 1/8”. For the
inner connection extrude the top half 1/8” +
1/16” and the bottom half -1/8” - 1/32”. Link
complete.
3.2 Locking Block
Step #2.1: Started a new sketch from XY
plane datum, use the line and arc tool to create
the generic shape for the locking block
Step #2.2 Use the arc by center tool and
create two reference arcs (brown path).
Created one tooth with the proper length
and angle, then use pattern curve to create
the row of teeth around that portion of the
curve.

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Step #2.3: Extrude the main body
symmetrically over the datum by 1/8”.
Step ##2.4: Extrude the connection point with
two different depths: the top half having a depth
of 1/8”+1/16” and the bottom half being -1/8”-
1/32” from the datum.
Step ##2.6: Use the edge blend tool to round
the “lip” of the locking block.

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Step ##2.7: Locking Block Complete
3.3 Sliding Block
Step #3.1: Started a new sketch from XY plane datum, draw
shape of sketch with straight line tool. Give angle constrains
to the inner connection points.
Step #3.2: Add a circle that is tangent to the left and
upper portion of the box in order to fillet the top portion
of the sliding block easier. Then used the fillet tool to
trim the edges within the box to the appropriate radius.

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Step #3.3: Extrude the body symmetrically by 1/8”. Sliding
Block complete.
3.4 Locking Nob
Step #4.1: Started a new sketch from XY
plane datum, create the inner rings of the
locking nob. Use the “Make Corner”
command to make the mouth of the
Locking Nob symmetric over the X axis.
Step #4.2: Use the fillet tool to
create the mouth of the locking nob

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Step #4.3: Extrude body to the largest length
using the symmetric value and a distance of
3/16”.
Step #4.4: With a new sketch, draw circles on the XY
plan to create the different depth layers of the Locking
Nob. Extrude 3/32” of depth for both the top and bottom
half of the locking block using the subtraction Boolean
command. Repeat with symmetric extrusions of 1/8” and
then 1/8” +1/32” -1/8” -1/16” for the top and bottom
middle layer respectfully.
Step #4.5: Next Use the chamfer tool to create a 1/64”
rounded edge between the outer circle and middle circle.

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Step #4.6: Use the chamfer tool again to create a 3/64”
rounded edge between the top and bottom faces of the
Nob.
Step #4.7: Finally create a 1/64” around the side of the
Nob.
Step #4.8: Use the offset curve to replicate the outer ring 1/64”
inward. Draw the teeth, making sure are the arc center command
is off and the teeth is vertically constrained and has a midpoint
constrain to the center of the XY plan datum. Make the slanted
slops of the teeth have equal lengths constrains. Use the parallel
feature to constrain the sides of the teeth.

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Step #4.9: Create two reference lines from
the teeth/gap to the XY datum. Make sure
you close the loop for the teeth extrusion.
Step #4.10: Use the pattern feature tool create the
row of teeth. Select the teeth extrusion and apply
the pattern around one half of the Locking Nob
Mouth. Make sure that that specific vector and
point is the Z axis and the origin respectfully.
Step #4.11: Locking Nob Complete.

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3.5 Jaw
Step #5.1: Started a new sketch from XY
plane datum with the generic sketch using
the profile line and arc tool. Constrain
accordingly using inferred dimensions
and radius constrains.
Step #5.2: Repeat same step as above for
the inner components of the Jaw. Then use
Region Boundary Curve extruding the
main body of the Jaw symmetrically by
9/32”.
Step #5.3: Next, the lip was extruded
symmetrically by 3/8”. Make sure that
the “None” is selected for Boolean.

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Step #5.4: edge blend the nose with radiuses of 1/16”
and ¼” on the top and bottom halves respectfully.
Step #5.5: Use the inferred
Datum plan command to create a
new plan that is normal to the
reference line.
Step #5.6: Create two parallel
lines and constrain the parallel
line to have an angle of 6° from
your new plan X-axis.

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Step #5.7: Create a closed loop
with the two parallel lines. Use
the subtractive extrusion. After
the extrusion, use the mirror
feature to copy the tapered cuts
to the bottom side of the Jaw.
Step #5.8: Unit the Jaw body and the lip of
the Jaw using the unit tool.
Step #5.9: Now to create the
hole going inside the body of the
Jaw, create a circle with
diameter of 9/8”. Create a line
that is perpendicular to the bass
of the Jaw from the circle was
then created. Close this loop

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Step #5.10: Use the
subtracted Boolean
command, extrude
symmetrically 1/8”
Step #5.11: Use the
chamfer tool to angle
the edges of the Jaw.
Step #5.12: Start a new sketch and drawing
the teeth in the sketch with a closed loop.
Make sure you are along the centerline body
of the Jaw since the Jaw is tapered. Use the
Subtraction Extrusion, the linear pattern
feature and the instant geometry feature to
create the pattern of teeth.

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Step #5.12: Jaw Complete.
3.6 Handle
Step #6.1: Open the Handle file that was initially given.
Create four new datum plan that is inferred from the XZ
plane in the negative y direction at 2, 2.2, 2.52, and 6.1
inches.
Step #6.2: On the first plane, the intersection point needs to be found
using the intersection tool and select the curve line along the Handle. This
will create a marker showing the intersection point of the curved line on
the Handle and the datum selected (blue plus). Turn it into a reference
point.

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Step #6.3: Make the box shape on the plane and
use the fillet tool, inferred dimensions tools and
midpoint constraint tool.
Step #6.4: Repeat Step #6.3 on the next three datum
planes.
Step #6.5: Create a new sketch on the original XY plan. Use the
straight line tool and the arc tool to connect the left most
rectangles. Use the Fillet tools to make sure the left guideline is
tangent to the body of the Handle.

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Step #6.6: Use the swept tool to create the rubber section of the
Handle. Make sure that tangent curve is selected and click on
the top section of each created rectangle. After each rectangle is
selected, click on “add new set” until all four rectangles are
picked. For the Guided selective curve, pick both the left and
right guidelines, and make sure that a new set was clicked after
selecting one of the sides. Use the cubic interpolation to make
sure the Handle is smooth if the linear interpolation produces an
undesired amount of sharpness along the curve of the Handle.
Step #6.7: Use the edge blend tool to finish the ascetic portion of
the Handle on both the top and bottom faces of the Handle.
Hallow out the Handle that was just created with the swept tool.
Use the extrude tool with the symmetric value and subtracted
Boolean selected.

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Step #6.7: Back Handle Complete
3.7 Jaw Handle
Step #7.1: Open the pre-
loaded Jaw Handle file and
start a new sketch from XY
plane datum. Draw the shape
of the Jaw Head using the line
and arc tool. Constrain
properly using inferred and
angular dimensions.

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Step #7.2: Extrude the top portion of the Jaw
Head symmetrically by .28” using the region
boundary option. Extrude the Middle section of
the Jaw Head symmetrically by .345” using the
region boundary option as well.
Step #7.3: To tapper the Jaw Head, create a new
inferred datum at the reference line.
Step #7.4: Create two parallel lines that are 5
degrees below the x plane. Use the point on
curve constraint to ensure the parallel lines
are in referenced to the y axis on this datum.
Step #7.5: Use the subtract Boolean
command when extruding, then use
the mirror feature to copy the tapper
work to the other side of the Jaw.

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Step #7.6: Unit the mouth of the Jaw to the Jaw Handle.
Step #7.7: Select a new on curve datum plan and place three datum
plans in there approximant location along the line. For the final
datum. Place it -0.3 inches away from the end of the handle
Step #7.8: Just like the Handle portion of this project,
draw the appropriate figure on the first datum along the
handle. Use the intersect point tool to place the reference
point on the datum and the curve, and use the
rectangular, fillets and constraints where needed.

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Step #7.9: Repeat Step #7.8: on the second (2nd
) datum and fourth
(4th
) datum. For the third datum (3rd
), project the whole sketch
from the first (1st
) datum onto the third (3rd
) datum.
Step #7.10: Now use the swept tool to
pick each section along the handle. Use
the connected curve and pick the top
line for each rectangular profile. Click
on “add new set” after each rectangular
is selected. For the guide curve, select
the left side with the tangent curve. For
the right, use the single curve and cubic
interpolation to smooth out the handle.
Step #7.11: To create the hole in the handle and the slot,
extrude and use the subtract Boolean command where
needed. Edge blend where deemed appropriate.

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Step #7.11: Jaw Handle Complete.
4. Assembly & Drafting
4 .1 Assembly
Step #A.1: Load the Jaw Handle, Jaw, and the
handle pieces. Fix the Jaw Handle on the origin.

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Step #A.2: Use assembly constraint and the touch align
command to align the inner portion of the Jaw to the Jaw
Handle.
Step #A.3: Then use the center and 2 to 2 option command
to align the Jaw to the Jaw Handle.

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Step #A.4: Next to align the Jaw and handle constrain the
two holes for each object with the touch align and infer
center/axis operation selected.
Step #A.5: To align the holes along the z axis
properly, use the center assembly constraint and
the 2 to 2 option to pick the faces of the Jaw and
the Handle.
Step #A.5.2: When aligned

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Step #A.6: Next add the Link,
Locking Nob, and Locking
Block into the assembly.
Constrain the Link with the
Touch Align and Infer
Center/axis option to the Pre
made “metal” portion of the
handle file.
Step #A.6.2: Repeat Step #A.6: for the
Locking Nob
Step #A.6.3: Repeat Step #A.6: for the
Locking Block

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Step #A.7: Use the touch
align to attach the other
part of the Link to the Jaw
Handle slit wth the prefer
touch option.
Step #A.8: Use the distance
assembly constraint and select the
centerline of both the arc at the
top of the slit and the handle nob
to constrain it approximately .1”
away from the centerline.
Step #A.9: Add the Sliding Block and use
the touch align constraint to place the
block against the back face of the Jaw
Handle.

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Step #A.10: Use the
center constrain and the 2
to 2 option to align the
Sliding Block to the
Handle
Step #A.11: Use the touch
to align and preferred
touch option to align the
Sliding block to the
Handle so that the
pivoting mechanism will
work. Note that the
objects wont look
perfectly aligned but as
long as the handle can
move while keeping the
connection together then the alignment was successful.

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Step #A.12: If the link slips
out of the slit of the Jaw
handle, use another distance
constraint and select the
centerline of the cylindrical
face at the bottom of the slit.

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Step #A.13: Final Assembly Complete-Side By Side view of Original Ratch-N-Lock Pliers

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4 .2 Part Drafting
Choose ONE part to create a drafting. The drafting should include at least 2 base views, 1
section view, and proper amount of dimensions.

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5. FEM Model Overview
The following is a detailed section of the steps taken to create the FEM modle for the Ratch-N-
Lock. The purpose of the FEM model is to create an analysis of forces that can be applied to the
Ratch-N-Lock and what forces the Pliers will experience when given certain conditions. For this
project, a static analysis was performed by creating the FEM to squeeze down on a nylon bar.
With this simply movement, an analysis of the forces that are applied to the connection points,
handle, and Jaw can be analyzed visual in FIGURE #9 below. Using 1,2, and 3-D meshes,
different connections types (pin , ball joints, and glue to be exact) where mimicked, in order to
secure the Pliers properly After creating the connection joins, the proper material, resistance, and
forces where applied appropriately. Hand calculations will be referenced in the Appendix that
will support the FEM calculations and show an approximant error between the two calculations.
Figure #9: FEM Figures of Ratch-N-Lock
6. Idealized Part
Step #1. FEM Open applicable file to commence
finite element model (FEM). Start a
new simulation. Select Upper, Jaw
Handle, and Connection_Bar.

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Step #2. FEM Select the Jaw Handle, and
make sure the Progressive
strategy option is selected.
Click on the
“Automatically create Face
Pairs.” This will create a
midsurface for the Jaw
Handle. After applying the
command, repeat for the
connection bar.
Step #3. FEM For the Jaw, we will split it into
two different sections along the
XY plane. Pick the “New Plane”
tool option then the XY plane.
Notice the line in the running in
the center Jaw.

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Step #4. FEM Now to
split the
jaw handle,
select the
split body
command,
select both
the Jaw
Handle and
the mid-
surface of
the Jaw
Handle,
under the
tool option select “New Plane” and “on curve is selected. Use the single
body line curve selection to choose the proper curve along the Jaw Handle.
Finally made sure the plan is at 0 distance.
Step #5. FEM In FEM, select the 3D
tetrahedral Mesh with the
“CTETRA(4) type and
element size of 0.075. Select
the Lower Jaw, Handle,
Stopping Block, and solid
Jaw Handle.

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Step #6. FEM Now repeat the same steps as above for half of the Upper Jaw. Make sure only
half of the jaw
is selected. Go
to Insert,
Element, copy
and reflect the
mesh along the
XY plan.
Step #7. FEM Blend and merge the two
meshes together.
Step #8. FEM Turn on the internal
display nodes of the
Upper Jaw by selecting
the mesh profile of the
Jaw, edited display then
select, Display Internal
Element Edges.
TABULATED CHARACTERISTICS FOR MESH DATA
1D CBAR Between
Jaws
1D CBAR Between
Lower Jaw and
Handle
1D CBAR Between
Handle and Link
Fore Sections 1D
CBAR
Radius=0.0625” Radius=0.15625” Radius=0.0625”
Materials 1D CBAR Nylon Steel Steel

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7. FEM Assembly
Step #9. FEM Now 2D mesh the connection bar and Jaw Handle
with the CQUAD4 type and with an element size
off 0.05 and 0.075 respectively.
Step #10. FEM Extrude a 2D mesh by inserting an
element, and extrude. Extrude in both
the +z and –z direction.
Step #11. FEM Insert a 1D mesh node in between the mouth
of the Jaws by selecting Insert, Node, and
Node between Nodes, with the Between Two
Nodes type selected. Make sure that the two
middle nodes of each Jaw is selected. Give
the radius of the bar 0.0625 inches.

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Step #12. FEM Start with 2D
mesh of then
link. Insert a
node at the
center of the
bottom hole of
link. Make sure
the inferred
point is selected
so the circle of
the polygon can be selected. Create two nodes at the center.
Step #13. FEM Go to the
1D
connection
tab, change
the element
type to
RBE2.
Select only
one node in
the middle
for the
source. For the Target Node, select each corner of the mesh within the hole.
Step #14. FEM For the
handle,
repeat the
same
steps as
above.

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Step #15. FEM Both 1D spider meshes: RBE2 Link (red)
RBE2 Handle (yellow).
Step #16. FEM To connect
the meshes,
insert and
create a new
element.
Select the
CBUSH
type, and
select both
of the nodes
in the
middle of the 1D mesh.
Step #17. FEM Now
create
two
center
Node
between
the
handle and link like in STEP #14. Also create a node at the top and the
bottom of the handle holes

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Step #18. FEM Now create the new
spider connection
(RBE2) in the middle
of the link. Make
sure RBE2 is
selected.
Step #19. FEM Repeat
the last
step to
create the
spider
mesh
between
the holes
in the
handle.
Step #20. FEM Now connect the spider meshes between the handles. Insert,
create element and select the CBAR type element. Turn off
the link spider to ensure the 2nd
Node that hasn’t been used
is selected.

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Step #21. FEM Connect the mesh between the
link and the handle. Insert,
element, create, CBUSH. Make
sure to create a new mesh
destination. Select both node in
the middle of the spider mesh.
Step #22. FEM Create spider
mesh between
the lower Jaw
and the handle.
Step #23. FEM Select the two
nodes that was just
created for the
lower jaw. Make
sure to create two
nodes in the center
of the handle.
Step #24. FEM Create the spider mesh at the lower jaw
as before. To select the nodes along the
edge of the jaw you can use the feature
edge node drop down option. Rename
the Destination collector to Lower Jaw.

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Step #25. FEM To connect the lower jaw
spiders, create a pin.
Insert, element, CBAR,
and change the collector
name since it’s a new
collector dimension
within the Ratch-N-Lock
Pliers.
Step #26. FEM To create the
spider mesh
inside the
handle,
change the
drop down
section
method to
“Feature
Angle
Nodes” when
selecting the
target nodes.
This will select the cylindrical surface of the handle. Put the destination ion
the handle section.

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Step #27. FEM To connect the Lower Jaw and
Handle, Insert element, create,
CBUSH, change destination to
the 1st
collector and create a new
mesh. Select the two nodes in
the middle spider mesh (yellow).
Step #28. FEM Create a ball join between Stopping
block and Handle. Insert node. Click in
middle between the handle and Stopping
black and make two nodes. Make sure
that Z=0.
Step #29. FEM Create a spider
mesh on the
nodes. Select
RBE2 and select
the destination
to the Handle.
Select 4 nodes
along the edge
of the handle
face.

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Step #30. FEM Repeat for the Stopping block change the
section method to “Feature Angle Nodes”
and change the angle to 5°.
Step #31. FEM Now connect using
CBUSH like Step
#27. Make sure to
create a new
destination of the
CBUSH.
Step #32. FEM To define the
degrees of
freedom, for the
CBUSH, right
click, then edit
(monkey wrench),
click on edit
again.

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Step #33. FEM Repeat for the 2nd
CBUSH on the handle
to stopping block.
Step #34. FEM For shell thickness, right click on the shell
of the link, edit and edit again, change the
default thickness to 0.125” inches and the
material to “steel”.
Step #35. FEM Repeat for the shell of the handle
with thickness of 0.375”.

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Step #36. FEM Repeat for the CBAR that is in between
the mouth of the Jaws by making the
material “nylon.”
Step #37. FEM Change the radius of the pin
connecting the Handle to the
Link to 0.0625”.
Step #38. FEM Change the
radius of the
pin
connecting
the Handle
to the
Lower Jaw
to 0.15625”.

45. John Benavides 45
TABULATED CHARACTERISTICS FOR MESH DATA
8. FEM Model Check
Step #39. FEM Use the element
edge to check
the bottom
connection
surface of the
Jaw Handle.
Now “glue” the
3D mesh and the
2D mesh
together along the Jaw Handle. If the normal direction is note facing twords
tteh 3D mesh of the Jaw Handle reverse the direction of the coresponding to
ensure the entire face is in the proper normal direction.
Fore Sections 1D
CBAR
Radius=0.0625” Radius=0.15625” Radius=0.0625”
Materials 1D CBAR Nylon Steel Steel
CBUSH Pin/Hinge Joints
(Handle Holes, Handle to
Link, Link to Jaw Handle)
CBUSH Ball Joints
(Sliding Block to Handle)
Stiffness 10e8 DOF 1-5
Free for DOF 6
10e8 DOF 1-3
Free for DOF 4-6

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Step #40. FEM Check the joint connections with “Show adjacent” command. This is to
ensure that the connections made early are in the proper order and connected
properly to the respected section of the pliers. For the Pins

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Step #41. FEM Repeat the above step for the Sliding Block
9. SIM Glue and Contact
Step #42. FEM In SIM use the
Surface to
surface gluning,
with manual
option. Select
the Upper Jaw
as the source
region.
Step #43. FEM Select the Lower Jaw
Handle as the target
region.

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Step #44. FEM Now we will create the
region first and select the
target or source region
later. Repeat on Jaw
Handle and lable g21.
Step #45. FEM Select the Lower Jaw Handle
and label g22.
Step #46. FEM Repeat and
lab the c11
(contact) for
the Jaw
Handle.

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Step #47. FEM Repeat and
label c12 for
the lower Jaw.
Make sure to
select the inner
edge of the
lower Jaw.
Step #48. FEM Repeat and label c21 for
the back of the handle.
Step #49. FEM Repeat and label c22 for the
sliding block.

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Step #50. FEM Now apply the appropriate source and target region for gluning all sections
appropriately. IE C21 for
source and C22 as target
region.
10. Loading and Support
Step #51. FEM Back to the Fem, go
to modified
coordinates under
nodes and selected
a nod on the end of
the handle that is on
the XY plan (ie 0 Z
coordinate).
Step #52. FEM Back to sim, place a
10 lb force on the
nod that has no z
cordinate and apply
the force twords the
Lower Jaw Handle.

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Step #53. FEM Repeate and create an
opisode force on the
other handle to create
and equal and oposite
force reaction.
Step #54. FEM Apply a fixed
constraint to
the middle of
the nylon bar.
Step #55. FEM User define
constraint and
kill the DOF
#3 and select
points that are
not in line on
the handle
ends and the
Sliding Block.
This is to
ensure that the
SIM won’t
consider and
friction forces
along the
Sliding Block. While the SIM would run, extra constraints have been placed

52. John Benavides 52
through the entire FEM process in order to simplify the results and forces
that will act on the Pliers.
11. Results and Verification
Final Displacement

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Stress Plot
Stress Plot at Desired Location

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Calculations
The following work, steps, and information on the calculations where provide from
Dr P.Richard Zarda, and Shenghong Zhang. The FBD and work for the Pliers can be found in
the “Appendix” of the report.
From Dr. Zard’s Free Body Diagram, the N (contact force) and X1 (force in nylon rod), where
found. To find N, the Sliding Block was assumed to be slightly off axis compared to the rest of
the Pliers. The Sliding Block was assumed to be frictionless in order to make the math easier.
Two formulas where related that involve N and X1 to solve the system of equations and the Low
Jaw is the key to obtain the system of equations. First the moment was found on the Jaw Handle
that was created from the force at the end of the handle. This was used to get an approximate
location of the center of moment along the Lower Jaw Handle. The force was then projected
along the Perpendicular vector of the Lower Jaw to the connection point between the Lower Jaw
and Handle. From here, the moment was taken, using the projected 10 pound force on the lower
handle was using with the corresponding distance between the handle and Lower Jaw connection
to get EQ1. The moment was taken again this time with respect of the Lower Jaw and the nylon
rod. Again, the force was projected to correspond with the distance of moment between the
connections points, giving us EQ2. Below is the corresponding work done by hand.

55. John Benavides 55
Below is the math to find the Bending stress of the 2D shell with the assistance of Shenghong
Zhang work.

56. John Benavides 56
Compared with the true simulation value as provided by Shenghong Zhang (-22.57868), my
corresponding values have a percent error of 0.2%.
Error Table
X N1 σ (Bending stress)
Hand Cal 21.314 234.35 2268
NX 22.624 233.4 2150
Error% 6.1% .4% 5.2%
12. Summary
As with all other engineering programs, Siemens NX software is design to make the job of an
engineer more efficient, and with this particular software, the job of creating and testing models
is indeed, much easier with the program. Creating the Rach-N-Lock pliers for this project was a
great way to learn and develop modeling and simulation skills.
The CAD portion of the project was a success as each individual piece was design as close as
possible and show great similarity to the original specifications of each part of the Ratch-N-Lock
Pliers. The assembly portion also appears to be successful as the Ratch-N-Lock Pliers function
in a realistic mater after all constraints where made. Like the CAD section, the simulation
conducted was also a success. The final result forces, as seen in the “Results” section, have a
0.2% error compared to Shenghong Zhang baseline results. While improvements can always be

57. John Benavides 57
made to both the model and simulation, the results show that I have learned and been able to
implement the knowledge I have learned over this past semester.
The key point I learned in the simulation and testing phase for this project was to understand the
1, 2 and 3D meshes that were used to connect each part within the project. Making proper uses of
the meshes and where to implement them, is key to obtain real world results and understanding
what forces might be applied to the object and how well the Pliers can handle the forces.
Understanding how each mesh works, especially when multiple meshes are used to the same
corresponding apart, goes a long way into seeing how these set of pliers, and any other modeled
object, will move and work in the real world.
Coming into this class, I was not a big fan of modeling programs, in fact I push this class off
because I dislike modeling. While I can’t say I love modeling and I am definitely no expert in the
class, my skills and enjoyment of the class increased each day and I can say that I am
knowledgeable and skilled in the Siemens NX modeling software where I hope to be able to
apply the skills and techniques learned to future school and work projects.
13. Appendix
13.1. Appendix for CAD
My work was based on the original dimensions, PowerPoints, and YouTube videos
provided by Shenghong Zhang and this project would not have been successful without his
work and help over the course of this project:
Video Guides
https://www.youtube.com/watch?v=0DCReZr6XFo
https://www.youtube.com/watch?v=qbQvHvXd8us
https://www.youtube.com/watch?v=VBHkpem8ozQ
https://www.youtube.com/watch?v=RSINc9Rs_3A
https://www.youtube.com/watch?v=-mKbbBUzYvk
https://www.youtube.com/watch?v=IieGBiwYS6U
https://www.youtube.com/watch?v=_oUfKHxvu2M
PowerPoints/ Drafting Drawings.
https://webcourses.ucf.edu/courses/1106171/files/folder/Midterm%2520Project/Drawings/Handl
e?preview=45653096

58. John Benavides 58
https://webcourses.ucf.edu/courses/1106171/files/folder/Midterm%2520Project/Drawings/Jaw_
Handle?preview=45764692
https://webcourses.ucf.edu/courses/1106171/files/folder/Midterm%2520Project/Drawings?previe
w=45542626
https://webcourses.ucf.edu/courses/1106171/files/folder/Midterm%2520Project/Drawings?previe
w=45577458
https://webcourses.ucf.edu/courses/1106171/files/folder/Midterm%2520Project/Drawings?previe
w=45368629
https://webcourses.ucf.edu/courses/1106171/files/folder/Midterm%2520Project/Drawings?previe
w=45368628
https://webcourses.ucf.edu/courses/1106171/files/folder/Midterm%2520Project/Drawings?previe
w=45523538
Modeling a Ratch-N-Lock Pliers
http://www.homedepot.com/p/Unbranded-8-in-Ratch-N-Lock-Pliers-013320/204468378
13.2. Appendix for FEM
Video Guides
https://www.youtube.com/watch?v=zjH3TSk2A8c
https://www.youtube.com/watch?v=ieCi8QGkOLQ
https://www.youtube.com/watch?v=LdtVKi0U8PY
PowerPoints/ Drafting Drawings.
https://webcourses.ucf.edu/courses/1106171/discussion_topics/3143556
https://webcourses.ucf.edu/courses/1106171/files/folder/Lab%2520Handout?preview=46089783
https://webcourses.ucf.edu/courses/1106171/files/folder/Lab%2520Handout?preview=46162670
https://webcourses.ucf.edu/courses/1106171/files/folder/Lab%2520Handout?preview=46308168
https://webcourses.ucf.edu/courses/1106171/files/folder/Lab%2520Handout?preview=46541283
Hand Calculations from Dr P.Richard Zarda,
https://webcourses.ucf.edu/courses/1106171/files/folder/Final%2520Project/Hand%2520Calculat
ion?preview=46512590