Name: Michael SherdAluminum Lamp Project
Date: 4/23/99
For: EGR 367
Attn: Dr. Hugh Jack
Summary: This report details the design and fabrication steps that were implemented for an aluminum lamp. This project is required this semester as part of EGR 367 (Manufacturing Processes). The fabricated materials for the lamp were provided by the Padnos School of Engineering machine shop. Additional features for the lamp were purchased. The final product is a working lamp, which is now in my bedroom.
Design: There are four parts to this lamp which needed to be designed. These parts consist of the shaft base, shaft, shaft base/shaft connecting screw, and the shaft/socket connecting screw. The details of each part are given in the following sections.
Shaft Base
The shaft base, to be fabricated from 2.00" aluminum round stock, is
mounted to a wooden base plate and supports the lamp shaft. The wooden
base plate was purchased at a local craft store. Three 1/4-20 screws,
drilled to a depth of 0.5" from the bottom, are used to secure the wooden
base plate to the shaft base. These tapped holes are 120 degrees
apart on a hole pattern diameter of 1.25". A 1/4" diameter hole is
drilled through the center of the shaft base that will allow the electrical
wire to pass through on up to the socket. A 7/16-20 tapped hole is
designed to house the base/shaft connecting screw. This hole is to
be tapped to a depth of 1.00" from the top of the shaft base. To
enhance appearance, a taper is to be cut from the top of the shaft base
(tpf = 4). The following drawing shows the shaft base designed.
Shaft
The shaft, fabricated from 1.25" aluminum round stock, is mounted to
the aluminum shaft base described in the previous section. To anchor
the shaft to the shaft base, a 7/16-20 tapped hole is to be fabricated
up the center of the shaft to a depth of 1". This tapped hole will
house the shaft/shaft base connecting screw. A 1/4" hole is drilled
through the center of the entire length of the shaft. This hole will
allow the wire to pass through up to the socket. The top of the shaft
is identical to the bottom of the shaft. A 7/16-20 tapped hole is
fabricated down the center of the shaft to a depth of 1". This tapped
hole will house the shaft/socket connecting screw. The outside of
the shaft consists of two tapers. These tapers (tpf = 2.25) are identical
and are designed to start on the top and bottom of the shaft (d = 1.25")
and taper toward the axial center of the shaft where they meet at the same
diameter (d = 0.5"). The following drawing shows the design of the
shaft.
Shaft Base/Shaft Connecting Screw
The key component that will keep the shaft on the shaft base is this
connecting screw. The screw, fabricated from 5/8" aluminum round
stock, is fabricated using the lathe and a 7/16-20 die. The finished
screw is 1.50" long. First, a 1/4" center hole is drilled through
the entire length of the screw to allow the wire to pass through.
Next, the stock is to be turned down to .43" diameter on the lathe.
This is the required diameter to turn the die over the entire length of
the screw.
Shaft/Socket Connecting Screw
This screw will connect the light socket to the top of the shaft.
Like the other screw, this screw is center drilled to 1/4" to allow the
wire to get to the socket. The screw is fabricated from 5/8" aluminum
round stock. The 7/16-20 die threads on the outside are cut to a
length of 1.00". The top of the screw is not threaded because the
socket is slid over the screw and is held on with a set screw. The
finished connecting screw is 1.50" long.
A design drawing of both screws is shown below.
The products fit together to make up the final product. An assembly
drawing is important to show how each part fits together. An assembly
drawing is shown below that details the placement of each part.
Three clearance holes were drilled through the wooden base plate for
the 1/4-20 screws that keep the base plate and the shaft base together.
A 1/4 center hole was also drilled in the base plate to allow the wire
to pass through. The set screw in the socket shown is what anchors
the socket to the shaft/socket connecting screw. Not pictured in the assembly
drawing is the light bulb, lampshade, and wire. These parts, along
with the items pictured in the assembly drawing, make up the final product.
Fabrication:
The fabrication was implemented using various machining equipment.
Each step required its own process. These steps and processes were
recorded along with the time taken to complete the step. The
Fabrication Steps table below details every step needed to turn the designed
lamp into a working product.
| PART | PROCESS # |
|
MACHINE | TIME (h:mm) |
| SHAFT BASE |
|
CUT 2.00" ROUND STOCK TO 3.25" LONG | SAW |
|
|
|
FINISH CUT BOTH ENDS | LATHE |
|
|
|
|
DRILL 1/4" CENTER HOLE THROUGH AXIALLY | LATHE |
|
|
|
|
DRILL AND TAP (3) 1/4-20 HOLES IN BOTTOM (.5" DEEP) | DRILL/HAND TAP |
|
|
|
|
DRILL AND TAP 7/16-20 HOLE IN TOP END CENTER (1.00" DEEP) | LATHE/HAND TAP |
|
|
|
|
CUT TAPER FROM TOP (TPF = 4.00) | LATHE |
|
|
|
|
|
CUT LIGHT SURFACE FINISH ON REMAINING EXTERNAL SHAFT | LATHE |
|
| SHAFT | 08 | CUT 1.25" ROUND STOCK TO 10" LONG | SAW | 0.10 |
| 09 | FINISH CUT BOTTOM END | LATHE | 0.05 | |
| 10 | DRILL 1/4" CENTER HOLE THROUGH AXIALLY | LATHE | 0.30 | |
| 11 | DRILL AND TAP 7/16-20 HOLE IN BOTTOM END CENTER (1.00" DEEP) | DRILL/HAND TAP | 0.10 | |
| 12 | DRILL TAP HOLE IN TOP 3" DEEP TO BE HAND TAPPED LATER | LATHE | 0.05 | |
| 13 | CUT EXTERNAL TAPERS (TPF = 2.25) | LATHE | 0.40 | |
| 14 | CUT 1.50" OFF TOP END OF SHAFT AT TAPER | SAW | 0.10 | |
| 15 | TAP 7/16-20 IN TOP HOLE PREVIOUSLY DRILLED (1.00" DEEP) | HAND TAP | 0.05 | |
| CONNECTING SCREWS | 16 | CUT (2) PIECES 3.50" LONG FROM 5/8" ROUND STOCK | SAW | 0.10 |
| 17 | DRILL 1/4" CENTER HOLE THRU BOTH PIECES AXIALLY | LATHE | 0.20 | |
| 18 | TURN EACH PIECE DOWN TO .43 DIA. OVER 1.5" LENGTH | LATHE | 0.25 | |
| 19 | CUT THREADS ON SHAFT BASE/SHAFT CONNECTING SCREW WITH 7/16-20 DIE. CUT THESE THREADS DOWN 1.50" FROM TOP OF SCREW | HAND DIE | 0.10 | |
| 20 | TURN END OF SHAFT/SOCKET SCREW DOWN TO 5/16". TURN THIS DOWN 0.50" FROM TOP OF SHAFT. | LATHE | 0.15 | |
| 21 | CUT THREADS ON SHAFT/SOCKET SCREW WITH 7/16-20 DIE. CUT THESE THREADS STARTING AT 0.50" FROM TOP OF SCREW DOWN 1.00" TO 1.50" FROM TOP OF SCREW. | HAND DIE | 0.10 | |
| 22 | CUT THE UNTHREADED ENDS OF BOTH PIECES AROUND | SAW | 0.10 |
Conclusion: The time taken to fabricate this project added up to 5 hours, 25 minutes. Recorded times include the setup time involved to start each process. All of the work was performed in the machine shop at Padnos School of Engineering. The machine shop has an extensive tool selection and no special tools were needed to complete the project. Most of the fabrication went smoothly. The process of cutting the external tapers on the shaft base and the shaft scared me at first because I had not done that before. This process wound up being fairly easy with a brief lesson from the machine shop supervisor. The process which I though would not be a problem but was was drilling the center hole axially through the entire length of the shaft. This was very time consuming, as the drill bit needed to be worked in and out of the hole periodically to allow the chips to escape. Overall, designing and then fabricating the lamp was a nice hands on project which clarified manufacturing processes and the process steps involved to complete a final product. The working lamp is shown in the picture below.
