This is the term project report for an Vice Grips Dissection, Optimization, and CAD Rendering project for ENGR 1120: Engineering Graphics Design, University of Georgia, Freshman Year

1. Vice-Grips Product Dissection Term Project
Bartholomew, Matthew
Wise, Jacob
8 December 2015

2. The first step of this assignment was fairly simple, to choose a product to dissect. Our
group chose to use Vice-Grips for two reasons. The first reason is simply that we didn’t know
what to use for this project and Ms. Tanner supplied a couple of items to choose from and Vice-
Grips sparked our interest. The second reason is that Jacob is a mechanic by trade and I have
done a lot of projects before so Vice-Grips are a tool both of us were already familiar with. This
style of Vice-Grips is derived from the original Vice-Grips locking pliers. The idea of Vice-
Grips was initially thought of by a farmer named William Petersen (Ganzel). Mr. Petersen found
“his job would be a lot easier if he had a set of pliers that would clamp down and hold the piece
of metal he was working on” (Ganzel). Mr. Petersen eventually developed a working prototype
of a product that incorporated both the functions of a vice as well as a set of pliers (Ganzel).
Soon, Petersen started selling to other local farmers and opened up a manufacturing plant in
1938(Ganzel). In 1941 Petersen’s plant started fulfilling contracts for both the US and England,
which was just what the company needed in order to survive (Ganzel). In 1985 Petersen
Manufacturing changed its name to American Tool Companies and in 1993 they obtained
IRWIN tool company (IRWIN).
Vice-Grips are a simple locking clamp-style mechanism that locks items between the
jaws of the tool. The product uses a screw mechanism on the upper handle that pushes on a
sliding lever permanently affixed to the lower handle in order to change the distance between the
jaws of the tool in the locked position (Appendix A). In order to unlock the jaws, the tool just
uses a simple lever mechanism attached to the lower handle. Overall the tool has 10 different
parts. The clamp consists of jaw pads, a fixed upper handle/jaw assembly, a moveable lower jaw,
a spring, a moveable lower handle, a screw, a release lever, a locking lever, and two different
sizes of rivets. The device relies on tension from the spring and screw in order to operate, it also
utilizes a simple lever mechanism in order to open back up. The device operates by the user
balling their hand into a fist, which pushes the handles together and engages the clamp. In the
diagram below you can observe a Black-box diagram that illustrates the general functionality of
the Vice-Grips. When the user inputs force and torque by balling their hand into a fist they
achieve the outputs of both noise and a clamped work piece.

3. INPUTS OUTPUTS
Force, torque Noise
Vice Grips
Work piece Clamped work piece
Tightened/loosened work piece
The Vice-Grips are riveted together so we weren’t able to do a lot of product
disassembly. Ultimately, the most disassembly we were able to do involved taking the spring out
of the work piece. In order to do this, we just used a simple pair of needle-nose pliers in order to
stretch the spring and take tension off of the handles. After we took it apart we then had to create
accurate measurements in order to recreate the tool in AutoCAD (Appendix B). The first step we
took in order to draw the tool in AutoCAD was to simply look at it as its various components in
order to make it a bit more manageable. In order to measure the parts, we used a pair of
electronic calipers. We used the electronic calipers because they are easy and quick to use as
well as very accurate. Due to the manufacturing and odd shape of most of the pieces of the Vice-
Grips they do not have very precise tolerances. This led us to modify or assume a lot of our
measurements in order to ensure that the parts fit together well. Below is a product
decomposition diagram for the Vice-Grips. This diagram illustrates the relationship between the
individual parts and subassemblies. For example, the Fixed Handle Subassembly is composed of
both the fixed handle and an adjustment screw. Also, it can be noted that within the Moveable
Handle Subassembly is the Compound Linkage Subassembly and that within this assembly is the
release lever as well as the locking lever.

4. Overall, the main function of the Vice-Grips is to clamp or tighten two work pieces
together. Sub-functions were determined by observing the device in operation and observing the
steps taken in order to properly use the device. By doing this we developed a set of critical-path
sub-functions that include adjusting the jaws, opening the jaws, clamping the work piece, and
tightening/loosening the work piece. The top half of the diagram below also shows a set of
secondary functions referred to as all-time functions. These are functions that we observed were
maintained at all times and were essential to device operation. These include maintaining jaw
separation via the spring, enhance handling comfort, attach spring, connect components, and
grasp tool.
Vice Grips
Fixed Handle
Subassembly
Fixed Handle
Adjusting Screw
Rivet Spring
Jaw
Jaw Pads Rivet
MoveableHandle
Subassembly
MoveableHandle Rivet
Compound
Linkage
Subassembly
Release Lever
Locking Lever

5. Ultimately, Vice-Grips have evolved throughout the years but could still use some
product improvement. As mentioned in the introduction the style of Vice-Grips we are using are
derived off of the locking plier style developed by Mr. Petersen. The only major change that the
original locking pliers developed was that in 1957 Mr. Petersen added the release lever to the
tool (Ganzel). The C-style clamp was derived from and operates in the same way as the initial
plier style; however, it is not published as to when this occurred. Even though our product is
fairly mature we still noted a few improvements that could be made in order for the product to
work better, be easier to use, and be more aesthetically pleasing. The first improvement that
could be made is to develop a rubberized coating on the handle. This would be molded in order
to increase user comfort as well as allowing for a better grip which would increase control of the
tool. The second improvement that could be made is a similar rubberized coating in order to
cover the jaw pads. Currently, the jaw pads are made of exposed metal, and while this might be
fine if you need to quickly clamp two sheets of metal together and weld them or something
similar it does little if you need to work or move the part and need a tool with a good grip. For
example, if the pads had a rubberized coating you may be able to use it to hold a sheet of metal
that you are bending or forging and you won’t have to worry about the metal slipping out of the
tool because the rubber had a better grip.

6. Works Cited
Ganzel, Bill. “Vise Grip.” The Vise Grip Company of Nebraska. Wessels Living History Farm,
n.d. Web. 2 Dec. 2015.
“IRWIN History.” IRWIN History- IRWIN Tools. IRWIN Tools, n.d. Web. 2 Dec. 2015.

7. Appendix A
The above image shows the tool during the product dissection with the spring removed.
The above image shows one angle of the adjusting/tension screw and locking lever functionality.

8. This image is a different angle showing the same screw and lever assembly, this time getting a
better view on the channel that the lever slides through.
This is a close-up image of the jaws and jaw pads showing how the jaw pads are shaped and
riveted onto the jaws so that they are free to swivel.

9. Appendix B
The following pages show the AutoCAD recreations of our Vice Grips. Page 1 depicts a fully
assembled and functional model of the Vice Grips. Page 2 features an exploded view of the tool
along with a Bill of Materials and leader lines to indicate different parts. The remainder of the
pages (3-8) depicts dimensioned 3-View Multiviews of the components. In the order they appear
they are: Bolt, Jaw Pad, Fixed Upper Handle Assembly, Moveable Lower Handle, Moveable
Lower Jaw, and the Locking Lever.