The document summarizes a technical report for a manufacturing processes lab project to machine a meat tenderizer. The tenderizer consists of a handle and head that are machined separately from aluminum stock and then joined. The summary describes the key steps to machine each part using various tools like a lathe, mill, and grinder. Calculations are provided for cutting speeds and feed rates during the different machining operations. The conclusion states that the handle and head were successfully machined to the proper shapes and joined with an all-thread fastener to complete the tenderizer.

1. TECHNICAL REPORT
MEAT TENDERIZER
FOR
MANUFACTURING PROCESSES LAB
ETME/SYEN 2117
DEPARTMENT of ENGINEERING TECHNOLOGY
UNIVERSITY of ARKANSAS / LITTLE ROCK
From
KENDRICK THOMAS
Lab partners:
JANNICE M. BONILLA
KRISTOPHER GRAVES
2801 S. University Ave.
Little Rock, AR 72204
5th May 2016

2. A. INTRODUCTION:
In this lab, students are to machine two objects, a tenderizer handle, and a
tenderizer head. The two objects will be machined from aluminum stock that is roughly
the size needed for the two objects, 1 inch diameter for the cylindrical stock for the
tenderizer handle, 1.5 inch height and depth for the rectangular stock for the tenderizer
head. The class cut both stocks to the desired size, one piece of each stock for all the
students. Once the objects are machined to the desired shape and size, the two objects
will be joined by an all thread fastener. The project spans approximately 6 lab periods,
provided that each group consists of 3 people and that each group machined one object at
a time to completion then moved on to the next object, while staying together on one
machine to provide support. In this lab three main machines were to be used the lathe, the
mill, and the grinder. All measurements to the thousandths place have a tolerance of
0.005 inches and measurements to the hundredths place have a tolerance of 0.01 inches.
All calculated values (spindle speed, feed rates, depth of cut, etc.) will be explained in the
calculations section.

3. B. PROCEDURE:
a. In order to complete this project successfully and safely, all individuals in the machine
shop must observe and practice all safety practices and rules. The following are a few of the
safety practices that all individuals in the lab must be aware of.
i. Safety goggles must be worn at all times especially while machining.
ii. Long hair must be contained, lab appropriate attire must be worn, and all jewelry must be
removed.
iii. Acknowledge and observe the emergency safety stop switches located on the machines
and in the lab.
iv. Do not operate the machines if one is currently under the influence of any substances that
may hinder one's performance.
v. Do not operate machines unless under proper supervision.
vi. Always ensure workpieces being machined are properly secured.
b. Using the horizontal band saw cut the cylindrical aluminum bar stock to a length of 8.5
inches; the bar stock is cut 1 inch longer than the finished dimension to give a surface to secure
in the chuck when knurling and to also give the option to keep the excess 1 inch. Using the
horizontal band saw again, cut the rectangular aluminum bar stock to 2.650 inches.
c. The horizontal band saw is not an accurate machine and the surface finish left on the cuts
are rough and undesirable for a surface finish. Gather the tools needed and obtain the proper
milling tool box. On the mill secure the tenderizer head (rectangular bar stock) square in the mill
vise grips ; the ends cut by the horizontal band saw are not square, so to accommodate this when
face milling, position the workpiece with one cut side up and square two uncut sides to the mill
vise grips and use a squaring ruler to square the third side; maintain a gap between the bottom

4. cut surface of the workpiece and the horizontal square surface of the mill vise grip. In the bottom
of the spindle secure a ⅝ collet and screw a ⅝ 2 flute mill cutter into the collet. Set the spindle
speed of the mill to 1920 sfpm. Once both cut ends of the workpiece are face milled, remove the
workpiece and debur it, debur between surfacing ends if needed. Inspect the square of the facing
against a square block. Once satisfied with the facing, debur the workpiece and measure its
height, the final height of the workpiece should be 2.50 inches. If needed, face mill the
workpiece to the correct height.
d. Like the tenderizer handle, the tenderizer head needs to be center drilled, drilled, and
tapped. Unlike with the tenderizer handle the mill is not self centering, to accommodate this use
an edge finder to find the center of the workpiece. Secure a drill chuck into the bottom of the
spindle, then secure the edge finder into the drill chuck, and set the spindle speed to 1000 rpm.
Secure the workpiece squared in the vise grips with an uncut surface facing up. The edge finder
will offset once it contacts the workpiece edge. Once the edge is found move the workpiece in
1.25 inches plus the radius of the edge finder which was 0.56 inches. Repeat this for the side
perpendicular, except the workpiece will move in 0.750 inches plus the radius of the edge finder.
Once the center of the workpiece is found, raise the spindle up in height away from the
workpiece and remove the edge finder, but do not move the spindle in any other directions. Insert
a #2 center drill into the drill chuck and center drill the workpiece using the same process from
the tenderizer handle set the spindle speed to 2720 rpm. Once center drilled, insert a 5/16 drill bit
into the drill chuck and set the spindle speed to 2720 rpm. Drill the hole to a depth of 1.000
inches, then remove the drill bit and tap the hole using the same process and tap handle used on
the tenderize handle.

5. e. To create the tenderizer teeth on both cut ends of the tenderizer head, use a 60o
mill cutter
with 20 teeth, a thickness of 0.517 inches, and a diameter of 3 inches. It is advised to set the
spindle speed to 200 rpm. Using 1.000 inch parallels secure the workpiece in the vise grips
leaving the edge to be milled available horizontally. Zero the mill cutter on both the x and z axis
of the mill to the workpiece accommodate for the thickness of the mill cutter by moving the
workpiece up 0.2585 inches. Move the workpiece into the mill cutter for a depth of cut of 0.130
inches in intervals of 0.050,0.050, and 0.030 inches. Once this is finished move the workpiece
out to clear the x axis zero, then rezero again and move the workpiece up 0.150 inches. Repeat
this process until 10 rows are made. Once this is finished, rotate the workpiece and recenter zero
using square blocks to avoid having to manually rezero the mill cutter. and repeat the process
making perpendicular cuts to form the teeth. After the first side is done debur and flip the
workpiece over and repeat on the other side. There is also the option to increase the distance
between cuts to 0.300 inches forming larger teeth.
f. Once finished with all processes on the mill, clean up the mill area and return all tools
and tool boxes to their proper place.
g. Gather the tools needed and obtain the proper lathe tool box. On the lathe center and
secure the tenderizer handle (cylinder) into the lathe chuck and set the spindle speed to 1400
rpm. The first operation on the lathe should be facing both sides of the tenderizer handle. To
accomplish this, use a high speed steel right-cut roughing cutting tool; secure this tool in the tool
holder on the tool post. Before each operation, ensure that the cutting tool is centered to the
workpiece. Once both sides of the handle are faced, remove the part, debur, and measure the
height of the workpiece. There is no need to face to length at this time because that operation
will come later if one opts to remove the excess 1 inch.

6. h. Rearrange the lathe so that the workpiece is able to be center drilled using a #2 center
drill with a diameter of 0.186 inches. Secure the center drill in a drill chuck using the tailstock,
and set the spindle speed to 2000 rpm or the nearest speed. While center drilling both ends of the
workpiece ensure center drill enters the workpiece to approximately halfway through the main
center drill taper; do not go past the end of the taper. Once both ends are center drilled, remove
the center drill, insert a 5/16 drill bit into the drill chuck, and set the spindle speed to 2000 rpm.
Drill a hole into one end only at a depth of cut of 1.00 inch. Once the hole is drilled remove the
drill bit and use a 3/8” tap handle to manually create the internal threads in the hole. To tap the
hole twist the tap handle by hand 3-4 times then reverse twisting until resistance decreases, then
repeat the process several times until significant resistance going in is met.
i. To create the double taper on the workpiece position the tool post on the lathe at a 90.00o
angle to the workpiece (0.00o
on the tool post) to make the step that will become the outside
diameter of the taper set the spindle speed to 1400 rpm. The double tapers will be on the same
end of the workpiece that was drilled and tapped. To accurately create the desired outside
diameter measure the current diameter of the workpiece to find the total depth of cut. The final
outside diameter of the first taper should be 0.875 inches; to accomplish this create a step of a
diameter of 0.875 inches for a length of 1.826 inches. Once this step has been made change the
angle of the tool post to 4.00o
to the left and mark the surface to be cut with ink and create the
taper going from right to left on the outside of the workpiece using a HSS right roughing cutting
tool until the taper reaches the edge of the outside diameter uniformly; ensure that the cutting
tool post has enough clearance from the lathe chuck. The second tapers outside diameter is the
same as the workpieces original diameter so there is no need to create a step. Position the tool
post to 5.00o
to the right, keeping the spindle speed and the cutting tool the same. This taper will

7. start from the end of the first taper and end when it meets the outside diameter of the workpiece
at a length of 4.00 inches.
j. To knurl a pattern onto the workpiece secure the knurling tool onto the tool post. Using
the excess 1.000 inch material on the end of the tenderizer handle not drilled and taped secure the
workpiece into the lathe chuck. Using the dead center in the tailstock move the center into the
drilled hole to support the workpiece. Knurl the workpiece from the end of the second taper
down a length of 3.50 inches. In this lab the instructor knurled the workpiece for the class.
k. Once finished with all processes on the lathe, clean up the lathe area and return all tools
and tool boxes to their proper place.
C. CONCLUSION:
Using cylindrical and rectangular aluminum bar stock, a tenderizer handle and a
tenderizer head were machined from their original dimensions to the proper shape for a
meat tenderizer. This project had the ability for customization in the tenderizer handle by
opting to keep the excess 1.000 inch on the cylinder. On the tenderizer head, the
individual had the option to change the size of the teeth on one end. Once the desired
shape for both of the objects were reached, the tenderizer head and handle were joined
using a all thread rod fastener. Further work on the parts include deburring and sanding to
a smooth finish.

8. CALCULATIONS:
NS=(300 SFM * 4)1 in=1200 rpm NS=(800 SFM * 4)1 in=3200 rpm
The equations used to determine the theoretical range of acceptable spindle speeds when turning
on the lathe. The speed that was used was 1400 rpm.
fr=1400 rpm*0.005 in/rev=7 in/min fr=1400 rpm*0.015 in/rev=21 in/min
The equations used to determine the theoretical range of roughing feed rates when turning on the
lathe. However, since the actual feed rate was controlled by hand, there was not a way to
maintain a constant rate.
fr=1400 rpm*0.0015 in/rev=2.1 in/min fr=1400 rpm*0.005 in/rev=7 in/min
The equations used to determine the theoretical range of finishing feed rates when turning on the
lathe. As stated before, the actual feed rate was controlled by hand without a way to maintain a
specific rate.
NS=(300 SFM * 4)0.186 in= 6452 rpm
The equation used to determine the theoretical spindle speed when drilling with a #2 center
drill. Since the lathe was unable to reach this speed, the actual speed was 2000 rpm.
NS=(300 SFM * 4)0.3125 in= 3840 rpm
The equation used to determine the theoretical spindle speed when drilling with a 5/16” drill
bit. Once again, the lathe was unable to reach this speed, so the actual speed was 2000 rpm.
NS=(300 SFM * 4)0.625 in= 1920 rpm
The equation used to determine the theoretical spindle speed during the facing operation on the
milling machine with a 5/8” 2 flute endmill.
fr=0.005 in/tooth *2*1920 rpm=19.2 in/min

9. The equation used to determine the theoretical roughing feed rate when facing with the 5/8” 2
flute endmill. The milling machine’s feed rate was also hand-controlled, limiting the ability to
maintain a constant feed rate.
fr=0.002 in/tooth *2*1920 rpm=7.68 in/min
The equation used to determine the theoretical finishing feed rate when facing with the 5/8” 2
flute endmill. It would be difficult to maintain a constant feed rate due to it being hand-
controlled.
It was determined that the spindle speed while operating the edge finder had to be greater 1000
rpm.
NS=(300 SFM * 4)0.186 in= 6452 rpm
The equation used to determine the theoretical spindle speed when drilling with a #2 center
drill. Since the mlling machine was unable to reach this speed, the actual speed was 2720 rpm.
NS=(300 SFM * 4)0.3125 in= 3840 rpm
The equation used to determine the theoretical spindle speed when drilling with a 5/16” drill bit.
NS=(300 SFM * 4)2.750 in= 436 rpm
The equation used to determine the theoretical spindle speed when using the 60o
mill cutter. Due
to instructor intervention, the actual speed was set to 200 rpm.
fr=0.005 in/tooth *20*200 rpm=20 in/min
The equation used to determine the theoretical roughing feed rate when using the 60o
mill
cutter. Since the feed rate was only controlled by hand, the actual feed rate couldn’t be kept
constant.
fr=0.002 in/tooth *20*200 rpm=8 in/min
The equation used to determine the theoretical finishing feed rate when using the 60o
mill
cutter. With the hand-controlled feed rate, keeping the actual feed rate constant was unlikely.