CompTIA A+ Core Certification: The Basics of IT Hardware Part 5 -Multifunction Devices / Printers and Setting

220-1101: Objective 3.6: Given a scenario, deploy and configure multifunction devices/printers and settings.

When performing technical support in a small office/home office (SOHO) environment, a technician needs to keep machines and devices up and functioning so that staff can continue to be productive. IT personnel are often called to support printing machines, many of which are multifunction devices that incorporate copy, scan, and fax features. (Although many have claimed that faxing is an outdated technology, it is still commonly used and is considered more secure than email.)

Multifunction devices output hard-copy versions of files such as documents and photos that are stored on the computer. Most office printers are laser printers, but in a SOHO setting, you will find inkjet, thermal, impact, and virtual (software) technologies for document output. Printers and multifunction devices can connect to a computer’s USB via Bluetooth, Wi-Fi, cellular wireless networks, or directly to a wired Ethernet network.

Unboxing a Device/Setup Location Considerations
The multifunction device is really several complex devices packaged into one unit. Combining these devices does not simplify things; it multiplies the opportunities for operational problems. To minimize the potential issues, consider the following decisions.
Make sure the printer is accessible to all users. Choosing a central location with access to the network is a good start. Make sure there is room to store paper and toner supplies close by, and be sure that users can find instructions for troubleshooting paper jams and the like.

Appropriate Drivers for the Office Environment
Printers largely use one of two drivers to perform printing tasks. They differ in how they work and the machines they are designed to support. These drivers are Printer Control Language (PCL) and PostScript (PS).
- PCL is a common driver language used by many different printer companies. It works with many different operating systems. PCL uses the printer hardware to process the print job data, comprised of print and graphics. This can take work off the computer and speed the printing process. The PCL method of printing incurs a couple potential drawbacks. One is that, because the printer does the processing work, the print job output can vary, depending on the brand of printer. Another is that PCL is not usually supported by devices running on the macOS, which could be a problem in some environments.
- PostScript is also supported by many manufacturers, including Apple computers, but not as many as PCL. Unlike PCL, PS does not depend on the printer for processing the print job, so the printing could be slower than with PCL printers. The advantage is that the print jobs will be consistent, no matter where they are printed in the network.

Choosing the correct print driver for the work environment is an essential first step. The main differences between PCL and PostScript is that PCL is better for fast printing and is widely supported by many operating systems, whereas PostScript is better for printing more detailed graphics. Windows assists with downloading drivers and many other issues by going to the Printers & Scanners page in the Settings menu.

Configuration Settings
Typical configuration options for printers or multifunction devices include the following:
- Duplex (double-sided) printing: This option might be available on single-sided printers as well as true duplex (both sides of paper) printers. With a single-side printer, the duplex setting is used to determine how to position the paper for printing the second side.
- Collate setting: This setting is used when printing two or more copies of a document that has two or more pages. When the Collate setting is enabled, the printer prints each copy of page 1 before printing page 2, and so on. This is useful when creating print jobs for binding, stapling, or punching, but it is slower than uncollated print jobs.
- Orientation: Portrait (long side up) or landscape (short side up) can be selected automatically in some printer drivers, based on the orientation of the document to be printed. If the correct orientation is not selected automatically, choose it. Use Print Preview to help determine the setting needed.
- Print quality: Different quality settings are available, depending on the type of printer:

- With laser printers and multifunction devices, you might be able to select the desired resolution (dots per inch [DPI]). Higher DPI levels produce smoother text output and more finely detailed graphics, but they require more printer RAM. As an alternative, some drivers have options to enable smoother text printing or to adjust page compression.
- Instead of using specific resolutions, inkjet printers use quality settings such as High, Standard, Fast (Canon); Draft, Text, Text and Image, Photo, and Best Photo (Epson); and Draft, Normal, Best (HP). Each setting optimizes the size of the ink droplet and paper coverage for the best results with the specified paper.


Public/Shared Devices
Printer and multifunction devices can be shared between two or more computers by using USB, Serial, Ethernet, and wireless connectivity.
Serial (RS-232) and USB sharing involve using switch boxes that can be manually switched between devices or that can automatically detect print jobs and switch to the active computer. Serial switch boxes are obsolete for most tasks, and USB switch boxes are limited by the number of computers that can share a printer (typically two or four).
Both serial and USB printer sharing are also limited by relatively short cable runs and lack of management capabilities. Most wired printer/multifunction device sharing now uses Ethernet.

Integrated Ethernet Print/Multifunction Device Sharing
Most recent printers and multifunction devices include software with an integrated print server that has support for Ethernet network printing.

To configure them for sharing, follow these steps:
Step 1. Connect the printer or multifunction device to the network via an Ethernet (RJ-45) cable.
Step 2. Configure the printer or multifunction device to use Ethernet.
Step 3. Name the printer so that it can be located on the network.
Step 4. Specify whether the printer or device will get an IP address from a DHCP router.
Step 5. If you need to manually configure the IP address for the printer or device, determine which IP addresses on the network are not in use by DHCP and then manually assign the printer or device to one of those addresses.
Step 6. Record the configuration information for reuse. Some printers and devices print the information at the end of the setup process.

The figure below shows some print server setup dialog boxes from a typical small office printer with wireless Ethernet support.


Configuring a Printer as an Ethernet or Wireless Ethernet Print Server

A multifunction device has an Ethernet port that takes on a network IP address. To print to a network printer or device, you might need to install a network printer driver instead of the normal printer driver on the computer that will use the printer or multifunction device. To learn more about TCP/IP and DHCP, see, “Networking.”

Wireless Device Sharing Options
The two major network protocols used for wireless device sharing are Bluetooth and 802.11 (Wi-Fi). Bluetooth is suitable for very short-range sharing among a few devices, whereas 802.11-based print sharing supports a much larger number of guest devices over much longer ranges.

Bluetooth
Most printers with built-in Bluetooth support are portable or receipt printers.
Printers that lack Bluetooth support can use special Bluetooth adapters to connect with computers or mobile devices that use Bluetooth. Check with the printer device vendor for models that are compatible with a specific printer.
Before a computer or mobile device can connect to a printer or multifunction device using Bluetooth, both the computer/mobile device and the printer/multifunction device must have Bluetooth transceivers. Bluetooth support is common among laptop and mobile devices and can be added with a USB dongle to computers that lack Bluetooth support.

After enabling Bluetooth on the printer and computer, you must configure both for pairing and pair them before print jobs can be sent. For details, see Networking (802.11(a, b, g, n, ac, ax)

Most new printers and multifunction devices include some level of 802.11 (Wi-Fi) support. The configuration process is typically similar to that used for wired Ethernet, with the added step of specifying the wireless network’s SSID and encryption key (if used). When this configuration is complete, all devices on the network with the proper print driver can use the multifunction device.

Infrastructure vs. Ad Hoc
If you want to use wireless Ethernet (Wi-Fi) printers or multifunction devices but do not use Wi-Fi networking with a wireless router, configure the printers or devices to work in ad hoc mode. In ad hoc mode, each device is connected directly to other devices: No router is used.
Infrastructure mode supports WPA3 encryption; ad hoc mode supports only WEP encryption, making it unsuitable for secure networking.

Ad Hoc Wireless Network Support in Windows
Ad hoc wireless networking is supported in previous versions of Windows through the Network and Sharing Center or from the command line using Netsh, but it has been removed in Windows 10/11.

Ad Hoc Wireless Network Support in macOS
macOS supports ad hoc wireless networking through the Wi-Fi Status icon on the Finder menu. macOS refers to this feature as “computer-to-computer” networking.

. When you enable this feature, your computer cannot connect to other Wi-Fi networks at the same time.


Creating a Computer-to-Computer (Ad Hoc) Wireless Network with macOS

Ad Hoc Wireless Networking Support in Linux
Ad hoc wireless networking in Linux is sometimes referred to as an IBSS (independent basic service set) network. Depending on the distro, this can be set up by turning on the wireless hotspot service in the network settings or by using the command-line utilities iw and ip. Network Manager can be installed on distros that lack easy network management.

Wireless Hosted Networking
As a replacement for ad hoc mode, Windows 7 introduced wireless hosted networking, which is also available in Windows 10/11. With wireless hosted networking, you can create a Wi-Fi network hotspot that is detectable and usable by Wi-Fi-enabled printers and other computers and devices.

To create an unsecured wireless hosted network, open a command prompt and enter this command:
netsh wlan start hostednetwork
 

Check the Network and Sharing Center, or Network & Internet in Windows 11, to ensure that your new network is available.
Set up your printer or multifunction device to use the same network name. To print, have each user connect to that network. A printer or multifunction device can use only one network at a time, but computers can connect to this network and to other networks (including wireless networks) at the same time.

Using Public and Shared Devices
Sharing printers on a network previously required both the printer and the user to be on the same local network. Recent print-sharing technologies have made shared printing available beyond physical access to a printer.
Public cloud printing devices are available in some office supply stores, schools, and other business centers located in hotels and airports. The customer can submit print jobs via email, web interfacing, mobile apps, or special print drivers. Thus, public cloud printing is available to any type of computer or device that has Internet access. To receive the print job from the printer, the user must provide the credentials needed, such as a retrieval code or account code. Google Cloud Print is an example of a service that allows printing to a Web-enabled computer from anywhere on the Web, including using phones.
Thanks to public cloud printing services, users might no longer need to buy a printer they use only occasionally. For example, a person working remotely from home (or any user, for that matter) might have very little use for a printer or might not use it enough to justify the cost. When the rare print job is required, the user can instead send the document to an account at a neighborhood Office Depot or similar business and then go there and print from a professional machine by entering the code on the keypad.

Using Apps
Smartphones and tablets that run Android or Apple iOS operating systems typically install apps from their respective app stores to make cloud or remote printing possible.
Connect older printers and multifunction devices that do not have built-in Google Cloud Print support to a computer running Google Chrome, and enable its Google Cloud Print feature to enable cloud printing. The Google Print Connector can be used to enable multiple printers in businesses or schools to be used with Google Cloud Print.

Maintaining Data Privacy
When a document is sent to a printer, the print spooler creates a special print file. To prevent unauthorized users from opening the print file and extracting information from it, two methods can be used: user authentication and hard drive caching.

Using User Authentication/Audit Logs
User authentication (which matches print jobs to the IP address of the computer or device requesting the print job) can be enabled at the printer itself or by security settings used on Active Directory–enabled networks.
When user authentication is enabled in the printer (a common feature on enterprise-level print or multifunction devices), the user must provide the appropriate identification during the print process. On a macOS system, this can be done through the Job Log portion of the printer submenu (the same menu that includes sections for layout, print settings, and so on). On a Windows system, the printer driver or the network might prompt for this information.

Using Hard Drive Caching
On a system running Windows, print spool files are normally stored on the system hard drive at C:\Windows\system32\spool\PRINTERS. If a different location is desired, make sure the location is not shared on the network, to avoid access from unauthorized users.
The default location of the print spool files can be changed by selecting the printer or multifunction device in Devices and Printers, opening the Print Server Properties dialog box, clicking Advanced, clicking Change Advanced Settings, and specifying a different location.

Network Scan Services
Printing is not limited to paper in network printing. Three services that can use printing are printing to an email, printing to a folder on a network using the SMB protocol, and printing to or from the cloud.
These are variations of printing to a file, in which the document is printed to an Adobe .pdf file to be sent or shared. Other companies have developed their own methods of sharing print files.

Scanning to Email
Windows and other printing software allow you to scan a document with the multifunction device and have it sent to the user as a .pdf attachment. This requires a device that is networked and can interface with the organization’s email services.

To scan to email, follow these steps:
Step 1. Select to scan to an email from the menu.
Step 2. Enter in or select the receiver of the mail.
Step 3. Press Enter to scan.
The scanner generates a .pdf file, attaches it to an email, and sends it to the destination.

Scanning to an SMB Folder
As when scanning to an email, the printer must know the IP address of the server on the network that is hosting the destination folders for the document. When user permissions are authenticated, the user can create a shared folder on the network and then scan the document into it.

Cloud and Remote Printing
With cloud printing, you no longer need to be at your office or home office to make a printout. With remote printing, you can print a document stored on your host using your remote printer.
Cloud and remote printing require the following:
- A printer or multifunction device that can be accessed from the cloud or remotely via the Web.
- An app that supports remote or cloud printing. The printer settings are loaded into the app, and the cloud-based document is downloaded and printed from the mobile device.

Automatic Document Feeder/Flatbed Scanner
Automatic Document Feeder (ADF) is a feature found in printers, photocopiers, and scanners that automatically feeds a single sheet of paper from a stack of paper into the machine. This allows the user to print, scan, or copy without needing to manually feed the machine paper one at a time. Typically, ADFs are described by speed, pages per minute, and sheet capacity. A flatbed scanner is used to scan documents using the flatbed. Some flatbed scanners have an ADF and can scan multiple papers without human intervention.

Print Technologies
220-1101: Objective 3.7: Given a scenario, install and replace printer consumables.

Printing has long been one of the most common issues confronting help desk technicians. Although in many ways print technologies have become simpler over time, the skills of knowing printer types and being able to perform printer maintenance remain in high demand.

Laser Printers
A laser printer is a page printer that stores the entire contents of a page to be printed in its memory before printing it. By contrast, inkjet, thermal, and impact printers print a page as a series of narrow bands.

The major components of a laser printer include the following:
- Imaging drum: Applies the page image to the transfer belt or roller. It is frequently combined with the toner supply in a toner cartridge.
- Developer: Pulls toner from the toner supply and sends it to the imaging drum.
- Fuser assembly: Fuses the page image to the paper.
- Transfer belt (transfer roller): Transfers the page image from the drum to the page.
- Pickup rollers: Pick up paper.
- Paper separation pad (separate pad): Enables the pickup rollers to pick up only one sheet of paper at a time.
- Duplexing assembly (optional): Switches paper from the front to the back side so that the printer can print on both sides of the paper.

The following sections take a closer look at how these and other components work together to make laser printing possible.

Toner Cartridges
Most monochrome laser printers use toner cartridges that combine the imaging drum and the developer, along with a supply of black toner. This provides you with an efficient and easy way to replace the laser printer items with the greatest potential to wear out.
Depending on the model, a new toner cartridge might also require that you change a wiper used to remove excess toner during the fusing cycle. This is normally packaged with the toner cartridge.
When installing a toner cartridge, be sure to follow the directions for cleaning areas near the toner cartridge. Depending on the make and model of the laser printer, this can involve cleaning the mirror that reflects the laser beam, cleaning up stray toner, or cleaning the charging corona wire or conditioning rollers inside the printer. If you need to clean the charging corona wire (also called the primary corona wire on some models), the laser printer will contain a special tool for this purpose. The printer instruction manual shows you how to clean the item.
Keep the cartridge closed; it is sensitive to light, and leaving it out of the printer in room light can damage the enclosed imaging drum’s surface.

Warning: When you change a toner cartridge, take care to avoid getting toner on your face, hands, or clothing; it can leave a messy residue that is hard to clean. 

Laser Imaging Process
A laser printer is an example of a page printer. A page printer does not start printing until the entire page is received. At that point, the page is transferred to the print mechanism, which pulls the paper through the printer as the page is transferred from the printer to the paper.

Tip: To master this section, keep these tips in mind:
- Memorize the seven steps involved in laser printer imaging.
- Master the details of each step and their sequence.
- Be prepared to answer troubleshooting questions based on these steps.
The laser printing process often is referred to as the electrophotographic (EP) process.

Before the seven-step laser printing imaging process can take place, the following events must occur:
- Because laser printers are page based, a printer must receive an entire page before it can start printing.
- After the page has been received, the printer pulls a sheet of paper into the printer with its feed rollers.
After the paper has been fed into the print mechanism, a series of seven steps takes place, resulting in a printed page: processing, charging, exposing (also known as writing), developing, transferring, fusing, and cleaning.

The following section describes this process in more detail.

Steps 1–7 are identified in the figure below.


A Conceptual Drawing of a Typical Laser Printing Process


Tip: Make sure you know this exact order of the laser printer imaging process for the exam:
Step 1. Processing
Step 2. Charging
Step 3. Exposing
Step 4. Developing
Step 5. Transferring
Step 6. Fusing
Step 7. Cleaning

Also make sure you know the parts that make up a laser printer:
- Imaging drum
- Developer
- Fuser assembly
- Transfer belt
- Transfer roller
- Pickup rollers
- Separation pads
- Duplexing assembly
 

Step 1: Processing
The printer’s raster image processing engine receives the page, font, text, and graphics data from the printer driver; creates a page image; and stores it in memory. Depending on the amount of information on the page, compared to the amount of memory in the printer, the printer might need to compress the page image to store it. If not enough memory is available to store the page image, a memory error is triggered.
Step 2: Charging
During the charging process, the cylinder-shaped imaging drum receives an electrostatic charge of –600VDC (DC voltage) from a conditioning roller. (Older printers used a primary corona wire.) The smooth surface of the drum retains this charge uniformly over its entire surface. The drum is photosensitive and retains this charge only while kept in darkness.
Step 3: Exposing
During the exposing process, a moving mirror moves the laser beam across the surface of the drum. As it moves, the laser beam temporarily records the image of the page to be printed on the surface of the drum by reducing the voltage of the charge applied by the charger corona to –100VDC. Instead of using a laser beam, an LED printer activates its LED array to record the image on the page.
Step 4: Developing
During the developing process, the drum has toner applied to it from the developer; because the toner is electrostatic and is also at –600VDC, the toner stays on only the portions of the drum that have been reduced in voltage to create the image. It is not attracted to the rest of the drum because the toner and the drum are at the same voltage, and like charges repel each other. This “like charges repel” phenomenon is similar to two like poles of magnets repelling each other.
Step 5: Transferring
During the transferring process, while the sheet is being fed into the printer, it receives an electrostatic charge of +600VDC from a corona wire or roller; this enables it to attract toner from the drum, which is negatively charged (see step 3). As the drum’s surface moves close to the charged paper, the toner adhering to the drum is attracted to the electrostatically charged paper to create the printed page.
As the paper continues to move through the printer, its charge is canceled by a static eliminator strip so that the paper itself isn’t attracted to the drum.
Step 6: Fusing
During the fusing process, the printed sheet of paper is pulled through fuser rollers, using high temperatures (approximately 350° Fahrenheit) to heat the toner and press it into the paper. The printed image is slightly raised above the surface of the paper.
The paper is ejected into the paper tray, and the drum must be prepared for another page.
Step 7: Cleaning

To prepare the drum for a new page, the image of the preceding page placed on the drum by the laser or LED array (see step 3) is removed by a discharge lamp. During the cleaning process, toner that is not adhering to the surface of the drum is scraped from the drum’s surface for reuse.

Color Laser Printing Differences
Color laser printers differ from monochrome laser printers in two important ways: They include four different colors of toner (cyan, magenta, yellow, and black), and the imaging drum is separate from the toner. Thus, instead of waste toner being reused, as in a monochrome laser printer that has a toner cartridge with an integrated imaging drum, waste toner in a color printer is sent to a separate waste toner container.
Color laser printers use the same basic process as monochrome lasers, but some use a transfer belt instead of an imaging drum.

The use of a transfer belt enables all four colors (cyan, magenta, yellow, and black) to be placed on the paper at the same time, making color print speeds comparable to monochrome print speeds. When a transfer belt is used, the conditioning and transferring processes are performed on the transfer belt.


The Printing Process in a Typical Color Laser Printer That Uses a Transfer Belt


Laser Media Types
Laser printers use standard smooth-finish printer or copier paper. It is important to use labels and transparency media that are especially designed for laser printers: Other types of media might jam the printer or become distorted because of the high heat used in the laser printing process.
Labels made for copiers are not suitable for laser printers because they can come off the backing and stick to the printer’s internal components.

Laser Maintenance
The major elements in laser printer maintenance include replacing toner, applying maintenance kits, performing calibration (color lasers only), and cleaning.

Replacing Toner Cartridges
If a laser printer’s toner cartridge also includes the imaging drum, replacing the toner cartridge also involves replacing the imaging drum. Because the imaging drum’s surface can become damaged, leaving marks on print output, changing the toner cartridge is helpful in improving print quality.

Applying Maintenance Kits
Many HP and other laser printers feature components that should be replaced at periodic intervals. These components often include fuser assemblies, air filters, transfer rollers, pickup rollers, other types of rollers, and separation pads (separate pads). These components wear out over time and can usually be purchased as a maintenance kit (as well as separately).
A printer that uses a maintenance kit displays a message or an error code (such as “Perform printer maintenance” or “Perform user maintenance”) when the printer reaches the recommended page count for maintenance kit replacement. Depending on the printer model and whether it is used for color or monochrome printing, the recommended page count could be as few as 50,000 pages or as much as 300,000 pages (or more).
After a fuser assembly or full maintenance kit is installed in a laser printer, the page count must be reset; otherwise, you will not know when to perform recommended maintenance again. Typically, the page count is reset by pressing a specified combination of buttons on the printer’s control panel.

Note: If the printer is under a service contract or is being charged on a per-page (or per-click) basis, it is not recommended to reset the paper count after servicing. However, most laser printers print the page count when you perform a self-test.

Performing Calibration
Color laser printers should be calibrated if print quality declines. The printer calibration process on a color laser printer adjusts image density settings to make up for changes caused by environmental differences or aging print cartridges.
Some color laser printers perform automatic calibration, but you can also force the printer to perform calibration on an as-needed basis. See the instruction manual for your printer for details.

Note: Print quality is affected by many factors, such as the print resolution for graphics. The higher the dpi, the sharper and better the print quality; conversely, using an economy printing mode that uses less toner reduces print quality. A damaged imaging drum or dirty rollers can leave marks on the paper that detract from print quality. If a color laser printer requires four passes to print in color and the colors are not properly lined up (a process known as color registration), print quality will be affected.

Cleaning
Because laser printers use fine-grained powdered toner, keeping the inside of a laser printer clean is an important step in periodic maintenance. If you want to use a vacuum cleaner to pick up loose toner, be sure to use a vacuum cleaner that is designed to pick up toner: Toner particles are so small that they pass through conventional bags and filters. If you prefer to use a damp cloth, be sure to first turn off the laser printer and disconnect it from power.
To keep the paper path and rollers clean, use cleaning sheets made for laser printers, as follows:
Step 1. Insert the sheet into the manual feed tray on the laser printer.
Step 2. Create a short document with Notepad, WordPad, or some other text editor, and then print it on the sheet.
As the sheet passes through the printer, it cleans the rollers. If a specialized cleaning sheet is not available, you can also use transparency film designed for laser printers. Some laser printers use a special software program to print a cleaning pattern onto plain paper.

Note: Be sure to know how to maintain a laser printer for the 220-1101 exam: replacing toner, applying a maintenance kit, performing calibration, and cleaning.

Warning: Never use transparency media that is not designed for laser printers in a laser printer. Copier or inkjet media is not designed to handle the high heat of a laser printer and can melt or warp and possibly damage the printer.

Inkjet Printers
Inkjet printers are the most popular type of printer in small office/home office (SOHO) use. Their print quality can rival that of laser printers, and virtually all inkjet printers in use today can print both color and black text and photographs.
From a tightly spaced group of nozzles, inkjet printers spray controlled dots of ink onto the paper to form characters and graphics. On a typical 5,760×1,440dpi (dots per inch) printer, the number of nozzles can be as high as 180 for black ink and more than 50 per color (cyan, magenta, and yellow). The tiny ink droplet size and high nozzle density enable inkjet printers to perform the seemingly impossible at resolutions as high as 1,200dpi or higher: fully formed characters from what is actually a high-resolution, nonimpact, dot-matrix technology.
Inkjet printers are character/line printers. This means that they print one line at a time of single characters or graphics, up to the limit of the print head matrix. Inkjet printers are functionally fully formed character printers because their inkjet matrix of small droplets forming the image is so carefully controlled that individual dots are not visible. Larger characters are created by printing a portion of the characters across the page, advancing the page to allow the print head to print another portion of the characters, and so on until the entire line of characters is printed. Thus, an inkjet printer is both a character printer and a line printer because it must connect lines of printing to build large characters. Some inkjet printers require realignment after each ink cartridge/print head change to make sure that vertical lines formed by multiple print head passes stay straight; this realignment could be automatic or could require the user to start the process. With other models, alignment can be performed through a utility provided as part of the printer driver when print quality declines due to misalignment.

Inkjet Components
The essential components in the inkjet printing process include ink cartridges, print head, roller, paper feeder, duplexing assembly, carriage, and belt.

Note: Make sure you know these inkjet components for the 220-1101 exam.
Some inkjet printers use external ink tanks for longer ink life between refills.


A Typical Inkjet Printer with Its Cover Open


Inkjet Printing Process
Inkjet printers use ink cartridges filled with liquid ink for printing. Some older inkjet printers use a large tank of black ink and a second tank with separate compartments for each color (typically cyan, magenta, and yellow; some models feature light versions of some of these colors for better photo-printing quality). However, almost all inkjet printers produced for a number of years have used a separate cartridge for each color. This improves print economy for the user because only one color at a time needs to be replaced. With a multicolor cartridge, the entire cartridge needs to be replaced, even when only one of the colors runs out.

Note: Inkjet printers are sometimes referred to as CMYK devices because of the four ink colors used on most models: cyan, magenta, yellow, and black.
The carriage and belt mechanism moves the print head back and forth to place ink droplets as the paper passes through the printer. Depending on the printer, the print head might be incorporated into the ink tank; it might be a separate, user-replaceable item; or it might be built into the printer.
Some inkjet printers feature an extra-wide (more nozzles) print head or a dual print head for very speedy black printing. Some models enable the user to replace either the ink cartridge only or an assembly comprising the print head and a replaceable ink cartridge.

Note: On an inkjet printer, print quality settings are typically Good, Better, Best; or Text, Text and Image, Photo, and Best Photo. They are selected in the Printer Settings dialog box. However, clogged nozzles (leading to ink dropouts), mismatch of paper type setting to actual paper used, and dirty rollers reduce actual print quality.
An inkjet printer is only as good as its print head and ink cartridges. Clogged or damaged print heads or ink cartridges render a printer useless. If an inkjet printer fails after its warranty expires, you should carefully check service costs before repairing the unit. Failed inkjet printers are often “throwaway” models and can be replaced rather than repaired, even during the warranty period.

Warning: Inkjet printers should never be turned off by using the power switch on a surge protector; doing so prevents the printer from self-capping its ink cartridges, which is a major cause of service calls and printer failures. Cleaning the print head— either with the printer’s own cleaning feature, using a cleaning utility built into the printer driver, or with a moistened cleaning sheet—will restore most printers to service. Always use the printer’s own power switch, which enables the printer to protect the ink cartridges and properly perform other periodic tasks (such as self-cleaning).
Inkjet printers use two major methods to create the ink dots that make up the page. Most inkjet printers heat the ink to boiling and create a tiny bubble of ink that is allowed to escape through the print head onto the paper. This is the origin of the name BubbleJet for the Canon line of inkjet printers. Printers that use this method feature either ink cartridges that include the print head or print heads with removable ink cartridge inserts. If a print head gets severely clogged, you can simply replace the ink cartridge if the ink cartridge incorporates the print head.
Another popular method uses a piezoelectric crystal to distribute the ink through the print head. This method makes achieving high resolutions easier; the Epson printers using this method were the first to achieve 5,760×1,440dpi resolutions. This method also provides a longer print head life because the ink is not heated and cooled. However, the print heads are built into the printer, making a severely clogged print head harder to clean. Both types of inkjet printers are sometimes referred to as drop-on-demand printers.

The inkjet print process works as follows:
Step 1. A roller mechanism pulls the paper or media in a feed tray into position.
Step 2. The print head is suspended on a carriage over the paper and is moved across the paper by a belt. As the print head moves across the paper, it places black and color ink droplets, as directed by the printer driver.
Step 3. At the end of the line, the paper or media is advanced, and the print head either reverses direction and continues to print (often referred to as Hi-Speed mode), or returns to the left margin before printing continues.
Step 4. When the page print is completed, the media is ejected.

Inkjet Media Types
Inkjet printers can use the same types of paper and labels that laser printers can use. However, inkjet printers can also use special matte or glossy-coated paper and business card stock for presentation or photorealistic images. Transparency stock must be designed specifically for inkjet use. Because of improvements in media and print design, old inkjet photo paper should be recycled instead of used; older paper types have very slow drying times, compared to recent types.
When printing, be sure to select the correct media type in the printer driver, to avoid banding, overuse of ink, and other poor-quality results.

Inkjet Maintenance
Ink cartridge replacement, calibration, nozzle check, head cleaning, and jam clearing are the major elements involved in maintaining an inkjet printer.

Note: Make sure you know the elements of inkjet maintenance—ink cartridge replacement, calibration, nozzle check, head cleaning, and jam clearing—for the220-1101 exam.

Replacing Ink Cartridges
Use the Printing Preferences or Printer Properties dialog box (which varies by printer and operating system) to determine when it is time to purchase additional ink or replace the ink cartridges.


A Printer with Low Ink Levels, with the ! Indicating a Cartridge That Is Nearly Empty


Note: Most inkjet printers stop printing when one color runs out, even if that color is not being used in the current print job. Some printers offer to use a mixture of photo black and colors if the normal black ink runs low during a print job.
Some printers run automatic nozzle cleaning or calibration routines when you change ink cartridges. If the ink cartridge includes a print head, whenever you change the ink cartridge, you also change the print head. Consequently, replacing ink cartridges is the single best maintenance step you can perform on an inkjet printer.

Calibration
Inkjet printers might require or recommend some type of printer calibration—most typically, print head alignment. This process involves printing one or more sheets of paper and selecting the print setting that produces straight lines. Some printers perform this step automatically, and others require user intervention to determine the best setting.
Some inkjet printers can use two printing methods: unidirectional, in which the printer prints only when the print head is moving from left to right, and bidirectional, in which the printer prints when the print head is moving in either direction (left to right, or right to left). If the print head is misaligned, bidirectional printing (sometimes referred to as high-speed printing) will have much poorer print quality than unidirectional printing.
Be sure to align the print head as needed, using the calibration or alignment utility provided in the printer driver, to permit successful use of bidirectional printing.
To enable bidirectional printing, select the High Speed option (when it is offered) in the Print Preferences menu.


Aligning the Print Head (A) Helps Produce Better-Quality High-Speed (Bidirectional) Printing (B)


Note: With some printers, it might be necessary to realign the print head after changing ink cartridges. Some of these printers perform this task automatically; with others, it might be an optional utility that you can run on an as-needed basis.

Nozzle Check and Head Cleaning
Periodically, especially if a printer has not been used for a while or has been used only for monochrome printing, it is a good idea to use the nozzle check routine to verify that all the print heads’ nozzles are working correctly.
The nozzle check or pattern check routine prints a pattern that uses all of the nozzles in all of the print heads and displays the pattern’s correct appearance. Compare the printout to the onscreen display; if you see gaps or missing colors, activate the head-cleaning routine. Repeat these steps until the nozzle check printout matches the screen display. Keep in mind that performing a nozzle check uses ink.


The Pattern Check (Nozzle Check) Dialog Box from a Canon Inkjet Printer Driver’s Maintenance Tab

Depending on the printer, these options might be located in the Printer Preferences Maintenance section, a toolbox dialog box, or someplace like the printer’s onboard menu. See your printer’s documentation for details.

Warning: When using a Windows-provided printer driver, some printer options might not be available. Installing the latest available driver from the printer’s manufacturer is a good practice.

Thermal Printers
A thermal printer uses heat transfer to create text and graphics on the paper. Thermal printers are available using three different technologies:
- Dye sublimation, for high-quality printing
- Thermal wax transfer, similar to laser quality
- Direct thermal, the most common use of thermal printing, used in retail point-of-sale (POS) receipt printing
Each of these technologies has quite different processes, which are discussed in the following sections.

Thermal Feed Assembly and Heating Element
Thermal printers can use an impact print mechanism or a dye-sublimation technology to transfer images. Direct thermal printers use heat-sensitive paper (special thermal paper), whereas thermal transfer printers use a wax, resin, or dye ribbon to create the image. Some printers can use either heat-sensitive media or a ribbon.
The feed assembly on a typical thermal receipt or point-of-sale printer pulls paper from a roll wound around a center plastic spool or spindle. The feed assembly on a typical desktop thermal barcode printer uses notched rollers and spring-loaded sprockets to advance roll paper. Larger thermal barcode printers might also use fanfold media as well as roll media.
The heating element in the print head is used to heat thermal paper or ribbons to make the image. Printers that use ribbons are thermal transfer printers, and printers that use thermal paper are known as direct thermal printers.

Thermal Printer Ribbons
Thermal transfer printers use wax- or resin-based ribbons, which are often bundled with paper made especially for the printer. Dye-sublimation (dye-sub) printers use dye-based film ribbons technology to print continuous-tone photographs. Examples of consumer-grade dye-sublimation printers include Kodak Printer Docks and the Canon Selphy CP series; these printers print 4×6-inch photos. Many vendors also sell larger-format dye-sublimation printers for use in photo labs and professional photography studios.



A Dye-Sublimation Ribbon for a 4-by-6-Inch Photo Printer (Canon Selphy CP)

Thermal Print Process
Although thermal transfer, direct thermal printing, and dye sublimation all involve heating the elements in a print head to a particular temperature to transfer the image, there are some differences in operation.

The basic process of thermal printing works like this:
Step 1. The print head has a matrix of dots that can be heated in various combinations to create text and graphics.
Step 2. The print head transfers text and graphics directly to heat-sensitive thermal paper in direct thermal printing, or to a ribbon that melts onto the paper in thermal transfer printing.
Step 3. If a multicolor ribbon is used on a thermal transfer or dye-sublimation printer, each ribbon is moved past the print head to print the appropriate color. In the case of dye-sublimation printers, the paper is moved back into position to enable the next color to be printed.
Step 4. When all colors have been printed, the paper is ejected.



Direct Thermal (Top) and Thermal Transfer (Bottom) Printing Technologies


Thermal Paper and Media
Direct thermal printers use special thermal (heat-sensitized) paper, and thermal transfer printers might use either standard copy paper or glossy photo paper, depending on their intended use.
If a printer uses direct thermal printing, heat-sensitive paper with characteristics matching the printer’s design specifications must be used. For portable printers that use direct thermal printing, such as the Brother PocketJet series, the usual source for such paper is the printer vendor or its authorized resellers. If the direct thermal printer is used for barcodes or point-of-sale (POS) transactions, you can get suitable paper or label stock from barcode or POS equipment suppliers and resellers.
Thermal transfer ribbons are available in three categories: wax (for paper—smooth paper produces the best results), wax/resin (synthetics), and resin (glossy, hard films, such as polyester). Choose the appropriate ribbon type for the material you will be printing on.
Dye-sublimation photo printers in the consumer space use special media kits that include both a ribbon and suitable photo paper stocks. Larger-format dye-sublimation printers are designed to print on standard-size and special-format roll and sheet dye-sublimation paper stocks, available separately from the ink or ribbon.

Thermal Maintenance
The elements of thermal printer maintenance include replacing the paper when it runs out, cleaning the heating element as directed, and removing debris from the heating element, rollers, or other components, as needed. For the 220-1101 exam, be sure to know the steps for thermal printer maintenance:
- Replace the paper.
- Clean the heating element.
- Remove debris.

Cleaning Heating Elements
Because the heating element in a thermal printer is the equivalent of the print head in impact or inkjet printers, it must be kept clean to provide maximum print quality. Many vendors recommend cleaning the print head after each roll of thermal transfer ribbon.
Some thermal transfer ribbons for POS and warehouse printers include special cleaning materials at the beginning of the roll. Some thermal printer vendors also supply special cleaning film you can use to remove dust, debris, and coating residue from print heads.
You can also use isopropyl alcohol to clean print heads; it is available in wipes, pens, pads, and swabs from various vendors. The ribbon must be removed before using isopropyl alcohol. When isopropyl alcohol is used in cleaning, it is essential to wait until the printer dries out before reinstalling the ribbon.

Removing Debris
Debris from torn paper, solid ink flakes, and label coatings can build up on rollers and other components, as well as on the print head. Use isopropyl alcohol wipes or other cleaning materials, as recommended by the printer supplier, to clean up debris for better print quality and longer print life.

Impact Printers
An impact printer is so named because it uses a mechanical print head that presses against an inked ribbon to print characters and graphics. Impact printers are the oldest printer technology, and they are primarily used today in industrial and point-of-sale applications.
Dot-matrix printers, the most common form of impact printers, are so named because they create the appearance of fully formed characters from dots placed on the page.

NOTE: For the 220-1101 exam, be sure to know the basic elements of impact printing:
- Print head
- Ribbon
- Tractor feed
- Impact paper

Impact Components and Print Process
Impact dot-matrix printers have a number of parts that move in coordination with each other during the printing process:
Step 1. The paper is moved past the print head vertically by pull or push tractors or by a platen.
Step 2. The print head moves across the paper horizontally, propelled along the print head carriage by a drive belt, printing as it moves from left to right. Bidirectional printing prints in both directions but is often disabled for high-quality printing because precisely aligning the printing is difficult.
Step 3. As the print head moves, the pins in the print head move in and out against an inked printer ribbon to form the text or create graphics.
Step 4. The ribbon is also moving, to reduce wear during the printing process.

These steps are repeated for each line until the page is printed.

The figure illustrates a typical impact dot-matrix printer. The model pictured is a wide-carriage version, but its features are typical of models that use either standard or wide-carriage paper.


Components of a Typical Impact Printer


Impact Print Heads
The most common types of print heads include 9-pin, 18-pin (two columns of 9 pins each), and 24-pin (which produces near letter quality, or NLQ, printing when used in best quality mode).

This figure shows actual print samples from a typical 9-pin printer’s draft mode, a typical 24-pin printer’s draft mode, and the near letter quality (NLQ) mode of the same 24-pin printer.


Actual Print Samples Illustrating the Differences in 24-Pin and 9-Pin Impact Printers


Note: The print samples shown in Figure 3-99 are taken from printers that use8.5–11-inch or wider paper sizes. The print head design and print quality vary greatly on printers that use smaller paper sizes in point-of-sale applications.

Impact Printer Ribbons
Printer ribbons for impact printers use various types of cartridge designs. Some span the entire width of the paper, and others snap over the print head.

This figure shows two types of ribbons for impact printers.


Typical Ribbons for Impact Printers


Impact Printer Paper Types
Impact printers use plain uncoated paper or labels in various widths and sizes. Impact printers designed for point-of-sale receipt printing might use roll paper or larger sizes of paper. When larger sizes of paper are used, these printers typically use a tractor feed mechanism to pull or push the paper past the print head. Tractor-feed printer paper and labels have fixed or removable sprocket holes on both sides of the paper. This type of media is often called impact, dot-matrix, continuous feed, or pin-feed paper or labels. Media with standard perforations can be difficult to separate from the paper edge after printing, but that paper is less likely to separate before use than microperforated media.
Multipart forms are frequently used with impact printers used in POS systems. Be sure to adjust the head gap appropriately, to avoid print head or ribbon damage.

Impact Printer Maintenance
The keys to successful maintenance of an impact printer include replacing the ribbon, replacing the print head, and replacing the paper.

Note: For the 220-1101 exam, be sure to know the basic elements of impact printer maintenance:
- Replace the ribbon.
- Replace the print head.
- Replace the paper.

Replacing the Ribbon
Keeping the ribbon fresh is important. Obviously, when the ribbon is worn, the quality of printing goes down. Furthermore, the ribbon on an impact dot-matrix printer lubricates the pins in the print head and protects the print head from impact damage. In addition to replacing the ribbon when print quality is no longer acceptable, be sure to immediately discard a ribbon that develops cuts or snags—a damaged ribbon can snag a print head pin and break or bend the pin.

Replacing the Print Head
If you replace ribbons when needed, you minimize the chances of needing to replace the print head. However, if a print head suffers damage to one or more pins, you must replace it. Damaged pins might snag the ribbon, and if a pin breaks, it will leave a gap in the characters output by the printer.

Replacing Paper
When you replace paper, be sure to check continuous-feed (tractor-feed) paper for problems with torn sprocket holes, separated tear-offs, and damaged sheets. Tear off any problem pages, and use only good paper from the stack in your printer.
Be sure the tractor feeders are properly adjusted, and if the printer can be run as either a push tractor (allowing zero-tear paper feed) or a pull tractor, be sure the printer is properly configured for the feed type.
Carefully check the head gap: Adjust it if you need to run multipart forms, thick labels, or envelopes. An incorrect head gap can lead to ribbon and print head damage.

3D Printers
3D printing is the common term given to what is technically known as additive manufacturing (AM). Several types of 3D printing exist, and changes are constantly occurring. Two popular types of desktop 3D printing are listed here:
- Fused deposition modeling (FDM): This is the most popular and approachable of 3D printing in a tabletop environment.
- Stereolithography (SLA): This is a newer 3D tabletop process that involves photopolymer resins and lasers. 3D printing is a relatively old technology, but key patents have expired and made it available to new markets. New ideas for products are being developed at a rapid rate.

Small FDM machines are common for hobbyists and small shops that need plastic components designed or manufactured onsite. SLA printers produce objects with higher detail but less strength than FDM printers, so they tend to be used for modeling and design work. Setting up and maintaining small 3D machines will be skills that are increasingly in demand among IT technicians.
As with other printers mentioned earlier in this section, you should know the basic process and parts of a 3D printer. The physical process of using an FDM printer can be compared to the process of using a household glue gun: A hard material is pushed into a heating chamber, and the melted material is carefully directed through a nozzle, where it cools and becomes part of another object. Of course, FDM is much more complex because of the software for 3D design and the mechanics of moving the nozzle precisely.

In the FDM printing process, an object is created by adding layers of material to form a complete object. The most common material is a strand of plastic filament that is fed from a spool to a moving printer head. The printer head heats the plastic and thinly layers it onto the printing platform in cross-sections that eventually build up into the 3D object that has been designed on the computer.

This process is carried out on a 3D printer using these four components:
- Filament: This is the material that is fed from a spool. It is usually plastic, although many different materials can be used. The two most common types of filament are polylactic acid (PLA) and acrylonitrile butadiene (ABS). The filament is the “ink” of an FDM printer and is available in various colors.
- Extruder: The extruder takes in the plastic filament and melts it.
- Nozzle: The nozzle is a small spray hole that emits the melted filament.
- Print bed: The bed is the platform on which the object is created. An FDM printer builds the object layer by layer, from the print bed up.

An SLA printer has a similar desktop footprint to an FDM printer and also builds objects by creating thin layers of strategically placed plastic; however, it uses a very different technology. Using a laser and mirrors below a bed of resin, SLA printers heat liquid resins with a laser to form thin layers of plastic. The laser light is directed to different points on the mirror and redirected to specific points of the resin for heating and fusing into a layer of plastic. When each new layer is added to the bottom, the object is pushed up. The result is an object printed in an inverted, or upside-down, position.
The SLA process delivers objects that are higher in detail and finish quality than FDM, but they are less robust and not strong enough for mechanical use.
 

The process of 3D printing with either printer is essentially the same:
Step 1. Design an object using computer-aided design (CAD) software. CAD software comes in a wide array of sophistication, and the processing demands on the computer can require enhanced GPUs.
Step 2. Convert the model to an STL (printing code) format.
Step 3. Set the print speed. (Slower speeds mean higher-quality printing. If you print too fast, melted filament will not set properly, so start at midrange settings.)
Step 4. Ensure that the correct temperature is chosen; different filaments (and even colors) can have variable melting points.
Step 5. Print.

Figure shows a 3D printer with yellow filament being used to print a bowl.


3D printing

Maintaining 3D Printers
As with all other printers, cleaning and lubrication are the essential maintenance tasks for performance. Special attention needs to be given in a few areas:
- Lubrications need to be heat resistant, or they can melt and become part of the printed object.
- Different brushes are needed to clean different parts. For example, stiff brass brushes are good for cleaning the outside of nozzles.
- Cleaning the filament between print jobs is important to ensure that the next job starts with a filament that is clean and at the correct temperature.