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Lab 03 - Maintenance Tools

Last edited 114 days ago by Diego Rafael Hernandez.

Overview

This lab introduces students to a set of essential measurement and assembly tools used in aviation maintenance: digital calipers, digital multimeters, crimping tools, and torque wrenches. Through hands-on exercises, you will learn how to measure dimensions with precision, test electrical continuity, create reliable wire connections, and properly torque fasteners. Each activity emphasizes accuracy, safety, and good technique, helping you build a foundation in tool use that is critical for quality control, system reliability, and professional practice.

Assignment

Caliper

WhatsApp-Image-2024-10-21-at-10.56.51-3.png
Figure 1: Digital Caliper

Introduction to Using Calipers

Digital Calipers are precision instruments that measure internal, external, and depth dimensions. They provide quick, accurate digital readouts, making them essential for ensuring proper fit, design accuracy, and quality control. This lab will cover how to read measurements and tips for practical use.

Equipment

Collect the following equipment
1 - Digital Calipers
1 - Socket

Making Measurements

In this section, you will measure the outer diameter, inner diameter, and depth of a socket.
Fill in your chosen socket size here:
.
Complete the below.
Measurements Table 2
Item
Item Dimension
Measurement (in)
Measurement (mm)
Image
Notes
3
Outer Diameter
0.61in
15.7
IMG_1175.HEIC
Open
Inner Diameter
0.53in
13.5mm
IMG_1177.HEIC
Open
Depth
0.59
15mm
IMG_1176.HEIC
Open

Questions

Answer the following questions about calipers. Use any resource (AI, Wikipedia, etc.).
What is the listed accuracy of the calipers?
What is the listed resolution of the calipers?
What is the difference between accuracy and resolution?
[ ]
What are two potential sources of systematic/random error?
[ ]

Digital Multimeter (DMM)

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Figure 2: Digital Multimeter

Introduction to Multimeters

Digital Multimeters (AstroAI AM33D) are handheld instruments used to measure voltage, current, resistance, and check continuity or diodes. They provide a digital readout and require the user to select the correct range before measuring, making them reliable tools for basic electrical testing.

Equipment

Collect the following equipment
1 - Digital Multimeter
1 - Believer DA-15 Cable

DMM Settings

In this section, you will learn about the different measurement settings available on a DMM, what it measures, and the range and limits.
Complete the below.
Setting Name
What it Measures
Range/Limit
Image
Volts AC
500 Volts AC
IMG_5076.jpeg
Amps DC
2000 Microamps
IMG_5075.jpeg
Amps DC
200 Miliamps
IMG_5074.jpeg
Diodes and Continuity
Diodes and Continuity
IMG_5073.jpeg
Ohm resistance
200 Megaohm resistance
IMG_5072.jpeg
Volts DC
2000 Milivolt DC
IMG_5071.jpeg
Volts DC
200 Volts DC
IMG_5070.jpeg
There are no rows in this table

Making Measurements

Now it’s time to put the DMM to use by using the continuity settings to learn the pinout of a DA-15 connector. D-subminiature or D-sub connectors are commonly used connectors in the digital signal world, and we will be working with the same connector used in the Believer wing section. Follow the steps below:
DA-15 Pinout Table 2
DA-15
Connector Name
Pin Number
1
DC positive
2
DC positive
3
Elevator, rudder, Aileron
2
4
Aileron
1
5
Rudder
1
6
Elevator
1
7
DC negative
8
DC negative
9
DC positive
10
DC positive
11
Aileron
3
12
Rudder
3
13
Elevator
3
14
DC negative
15
DC negative
There are no rows in this table

Questions

Answer the following questions about DMMs. Use any resource (AI, Wikipedia, etc.).
Modern DMMs protect themselves from overcurrent. What electrical safety device provides this protection?
The DMM has three ports/plugs on the bottom. Complete the table below, explaining what each port is for.
DMM Ports 2
Port Name
The common port (COM) serves as a ground or a neutral point for the DMM
Column 3
COM
Open
The common port (COM) serves as a ground or a neutral point for the DMM
VΩmA⎍
Open
This port is for measuring resistance, volts, small currents, and milliamps
10A_MAX_
Open
This port is used for measuring large currents up to 10amps. You must switch the red lead to the different port because the port is fused for protection
There are no rows in this table

Crimping

product_tittle-30532857_600x.png.webp
Figure 4: Wire crimper

Introduction to Crimping

Crimp Tools are used to join wires to connectors by compressing (or “crimping”) a metal sleeve around the wire. This creates a secure mechanical and electrical connection without the need for soldering.

Making Crimps

Follow the steps below to remanufacture a servo cable.
Crimp Analysis Table 2
Wire Gauge
Connector Type
Crimp Tool Slot Setting
Image of Crimp
Inspection
Reflection of Crimp
3
3
3
IMG_6939.jpg
Open
IMG_6940.jpg
Open
IMG_6938.jpg
Open

Questions

In aviation applications, why are crimps preferred over soldering?
[ ]

Torquing

Torque Wrenches are precision tools used to apply a specific amount of torque to a fastener, such as a bolt or nut. They ensure that parts are tightened enough to hold securely without being over-tightened, which can damage components.

Table Assembly

In this section, we will assemble a lab table. Follow the steps below.
Torque Table 2
Bolt Head Size
Specified Torque Value (LB IN)
Student Torque Setting
Instructor Sign-off
3
40
IMG_6943.jpg
64
IMG_6941.jpg
111
IMG_6942.jpg

Questions

Why is it important to always return a torque wrench to zero?
[ ]
Why is it important to use a torque wrench instead of just “tightening until it feels snug”?
[ ]

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