3D Printing with Delta Printers

355 Pages·2015·10.873 MB·English

by  Charles Bell (auth.)

3D Printing with Delta Printers Technology in AcTion™
Do you find yourself wondering what the fuss is about a delta Also available:
3D printer? Perhaps you’ve decided to buy one but all of 3 3D Printing
your 3D printing friends are busily perfecting their cartesian D
printers. Maybe you find yourself stymied by the fact that your with

delta printer has very different needs for setup, configuration,
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calibration, and maintenance than cartesian printers.
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3D Printing with Delta Printers contains detailed descriptions
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of the innovative delta design including unique hardware, software, n Delta Printers
and maintenance requirements. The book also covers tips for
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building your own delta printer as well as examples of common i

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enhancements.
This book will enable you to build, configure, and enhance your g
delta printer. The topics covered will reveal the often-mysterious
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nuances of the delta design that will enable your printer to compete
with the best of what your 3D printer friends can build. i
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Featured highlights include: D
• Anatomy of a delta printer e
• hardware and software specific to delta printers
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• Tips for a successful build t
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• Setup and calibration of a delta printer
• Maintenance tasks
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• Troubleshooting tasks
• common enhancements r
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Printers pictured on the front cover, from left to right: SeeMecnc
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Rostock Max v2, Mini Kossel, and Kossel Pro.
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ISBN 978-1-4842-1174-8
52999
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US $ 29.99 e
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Shelve in: Computer Hardware | General
User level: Beginning–Intermediate
9781484211748
Charles Bell
www.apress.com
For your convenience Apress has placed some of the front
matter material after the index. Please use the Bookmarks
and Contents at a Glance links to access them.
Contents at a Glance
About the Author �����������������������������������������������������������������������������������������������������xv
About the Technical Reviewer �������������������������������������������������������������������������������xvii
Acknowledgments ��������������������������������������������������������������������������������������������������xix
Introduction ������������������������������������������������������������������������������������������������������������xxi
■ Chapter 1: Introduction to Delta 3D Printers ���������������������������������������������������������1
■ Chapter 2: Delta Printer Hardware ����������������������������������������������������������������������39
■ Chapter 3: Delta Printer Software �����������������������������������������������������������������������71
■ Chapter 4: Tips for Building a Delta Printer �������������������������������������������������������119
■ Chapter 5: Calibrating the Printer ���������������������������������������������������������������������151
■ Chapter 6: Delta Printer Troubleshooting ����������������������������������������������������������211
■ Chapter 7: Delta Printer Maintenance ���������������������������������������������������������������257
■ Chapter 8: Delta Printer Enhancements ������������������������������������������������������������293
■ Appendix: Common Problems and Solutions �����������������������������������������������������323
Index ���������������������������������������������������������������������������������������������������������������������333
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Introduction
Delta printers are not the arcane engineering marvels or cantankerous contraptions that are usable only
by the most advanced enthusiasts. To use them, they neither require an engineering degree nor arcane
knowledge.
Intended Audience
I wrote this book to share my passion for all manner of 3D printers. I especially wanted to show how anyone
can use a delta printer and achieve the same level of enjoyment and success as the more popular Cartesian
3D printers.
This book therefore is for the novice and intermediate 3D enthusiast who wants to learn how delta
printers work and how to become an expert using them. Even enthusiasts who have been using their
Cartesian 3D printers for some time will find information in this book that will help further enhance
their skills.
More importantly, I wrote this book to help those who have become frustrated trying to learn how
to use a delta printer. I have read where some have given up on their printer, discarding it as hopeless, or
selling it to anyone willing to buy it for scrap. It is my hope that the popularity of delta printers will grow and
perhaps even compete with or even surpass that of Cartesian printers. Perhaps that is too much to wish for,
but if I get one person to turn their lament to enjoyment, I’ll be happy.
How This Book Is Structured
The book is written to guide the reader from a general knowledge of 3D printing to expertise in modifying
delta printers. The first several chapters cover general topics, including a short introduction to 3D printing,
the hardware of delta printers, and the software used. Additional chapters cover build tips, configuration,
and calibration. The book concludes with chapters covering delta printer maintenance and improvements.
■ Note this book is a natural companion to my book, Maintaining and Troubleshooting Your 3D Printer
(Apress, 2014). Readers who want a deeper understanding of maintenance and troubleshooting may want to
read this book as well. It may also be helpful for those who want to use both Cartesian and delta printers.
xxi
■ IntRoduCtIon
The following is a brief overview of each chapter included in this book.
• Chapter 1: Introduction to Delta 3D Printers. This chapter presents an introduction
to 3D printing, including the anatomy of a 3D delta printer and the types of filament
available.
• Chapter 2: Delta Printer Hardware. This chapter presents a detailed look at the
hardware used to construct delta printers, as well as a brief overview of the types of
delta printer designs.
• Chapter 3: Delta Printer Software. This chapter presents an overview of the software
used with 3D printing, with emphasis on the software supporting delta printers.
• Chapter 4: Tips for Building a Delta Printer. This chapter presents a set of best
practices and advice for those wishing to build their own delta printer. It offers
specific tips and covers the tools and skills required.
• Chapter 5: Calibrating the Printer. This chapter provides and in-depth look at how to
calibrate a delta printer. A thorough description and an example of all delta printer
calibration are included.
• Chapter 6: Delta Printer Troubleshooting. This chapter presents some of the most
common things that can go wrong and how to solve them. Topics range from first
layer issues, to curling and cracking, to hardware failures.
• Chapter 7: Delta Printer Maintenance. This printer presents best practices and
practical examples of how to maintain your delta printer.
• Chapter 8: Delta Printer Enhancements. This chapter describes some of the most
common enhancements available for delta printers, including those for the
Mini Kossel, Kossel Pro, and Rostock Max v2.
Appendix
This book includes an appendix that contains diagnostic charts to help you zero-in on the cause of a print
quality issues, failures, and other problems with hardware and software.
How to Use This Book
There are several ways that you can use this book, depending on your experience level, and, of course, the
time that you have to devote to study. After all, you want to enjoy your new acquisition, yes? The following
sections describe two likely levels of experience. You may find you fit both categories—that’s OK. The
sections are not intended as the only ways to read and apply the material presented. Indeed, you can read
it cover-to-cover or a single chapter at a time in any order. Only you know your needs. However, if you want
some guidance, I provide such in the following.
xxii
■ IntRoduCtIon
You Are New to 3D Printing and Delta Printers
This section is for those who are new to 3D printing and have either just bought a delta printer or plan to in
the near future. It also covers topics of interest to those who want to learn to build their own delta printer.
You will learn all about delta printers, including the hardware used to build them, as well as the software to
run them.
If this fits your needs, I recommend you read through the first five chapters of this book carefully before
trying to spend a lot of time with your printer. You may want to read Chapters 3, 4, and 5 twice before starting
to build or calibrate your delta printer.
The time you spend reading about calibration and proper setup may make the difference between
buyer’s remorse and enthusiasm.
Once you have your printer going and have had success printing several things, you can move on to
the remaining chapters, which will help you understand troubleshooting and the maintenance needs for
your printer.
You Own a Cartesian 3D Printer but Are New to Delta Printers
This section covers those who have had some experience with a 3D printer but want to learn about how
delta printers work, and more importantly, how to properly set up a delta printer to improve its print quality.
If this is you, I recommend skimming through the first three chapters of the book to ensure that you
have learned all the key concepts of delta printers. Even if you have already set up your own delta printer
and have installed the software, it is a good idea to read about these topics in a more general aspect. If
nothing else, you will see some of the choices you could make concerning filament, hardware, and software
solutions.
From there, I would recommend reading through the next four chapters, one chapter at a time, to apply
the techniques you’ve learned. This includes proper calibration, setup, maintenance, and troubleshooting
your prints.
The troubleshooting chapter alone is the one area where intermediate enthusiasts have a lot of
frustration. As I mention in the chapter, there are a lot of opinions and solutions out there for common
maladies; some are no more than voodoo or wishful thinking, some work for only a few people, and most are
too specific to a model or situation to be a general cure. If you are having print issues, you will learn many
solutions that can make almost all of your problems vanish.
Once you have your printer dialed in and your printing woes cured, take a look at the remaining chapter
to ensure that you are following proper maintenance to keep your printer running in top shape.
Downloading the Code
The code for the examples shown in this book is available on the Apress web site, www.apress.com. A link
can be found on the book’s information page under the Source Code/Downloads tab. This tab is located
underneath the Related Titles section of the page.
Contacting the Author
Should you have any questions or comments—or even spot a mistake you think I should know about—you
can contact the author at [email protected].
xxiii
Chapter 1
Introduction to Delta 3D Printers
The most fascinating three-dimensional (3D) printer design to watch print is the delta printer. The delta
design is quite different from most 3D printers and is best known for its vertical orientation and relatively
small footprint (although larger units can be quite tall). This book will help you learn what you need to buy
or build your own delta printer, as well as how to get the most out of your delta printer.
A delta 3D printer, hence delta printer, is a type of parallel robot that uses geometric algorithms to
position each of three vertical axes simultaneously to move the nozzle to any position in a cylindrical
build area. Thus, when the printer is printing, all three axes move in a mesmerizing ballet of mathematical
magic.1 If all this sounds too fantastic, don’t worry; I will present the mechanics of the delta printer in detail
throughout this book.
Before we jump into how the hardware mechanisms work, let’s take a short tour on what 3D printing is
all about. A firm understanding of the concepts of 3D printing is essential to getting the most out of your 3D
printer investment. Even if you are already a 3D printing enthusiast (and especially if you have never used a
delta printer), you may want to read the following sections because I present the material with delta printers
in mind.
Getting Started
The world of 3D printing is growing in popularity as more people find creative ways to use 3D printers.
People buy 3D printers for creating solutions for the home, gifts, artistic expression, and of course, for
rapid prototyping of components for manufacture. I have even seen 3D printers used in architectural
firms to replace the somewhat tedious art of 3D modeling2—from scale models of buildings to elaborate
terrain maps.
The major contributor for this expansion is that 3D printers are getting easier to find and afford. While
far from the point of finding a 3D printer in your local small retailer or as a bonus for buying a new mattress,
you don’t have to look very far to find a 3D printer manufacturer or reseller. Even printing supplies are
getting easier to find.
In fact, some of the larger retailers such as Home Depot are starting to stock 3D printers and supplies.
For some time now, MakerBot Industries has sold their products on the Microsoft online store, as well as at
their own retail stores. Similarly, other 3D printer suppliers have opened retail stores.
Naturally, nearly all 3D printing retailers have an online store where you can order anything from parts
to build or maintain your own, to printing supplies such as filament and other consumables. So the problem
that you are most likely to encounter is not finding a 3D printer, but rather it is choosing the printer that is
best for you.
1It’s at this point you may be wishing you paid more attention in trigonometry class.
2My early passion was architecture. I was quite good at making scale models, but not so much with tedious lettering
skills.
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Chapter 1 ■ IntroduCtIon to delta 3d prInters
Indeed, the challenges today are less about where to buy and more about whether to buy or build your
own from a kit (or from scratch), and if so, which kit to buy, which prebuilt printer to buy, what filament to
use, and perhaps more importantly, what printing technology you want to use.
Unless you have spent some time working with 3D printers and have mastered how to use them, the
myriad of choices may seem daunting and confusing. I have encountered a lot of people who, despite
researching their chosen printer, have many questions about how the printer works, what filament to use,
and even how to make the printer do what they want it to.
Too often I have discovered people selling their 3D printer because they cannot get decent print quality,
or it doesn’t print well, or they don’t have the time or skills to complete the build, or they have had trouble
getting the printer calibrated. Fortunately, most of these issues can be solved with a bit of knowledge and
some known best practices.
This section will help you avoid these pitfalls by introducing you to the fundamentals of 3D printing
with a specific emphasis on delta printers. You will learn that there are several forms of 3D printing and
be provided with an overview of the software you can use with your printer. You will also learn about the
consumables used in 3D printing, including the types of filament available. To round out the discussion on
getting started, I present a short overview on buying a delta printer, including whether to build or buy, and
what to consider when buying a used printer.
■ Note henceforth I will use “3d printer” and “printer” interchangeably since I will be talking only about
3d printers.
What Is 3D Printing?
Mastering the mysteries of 3D printing should be the goal of every 3D printing enthusiast. But where do you
find the information and how do you get started? This section presents the basics of 3D printing, beginning
with the process of 3D printing and followed by a discussion on how the printer assembles or prints an
object, and finally, it takes a look at the consumables involved in 3D printing. I will expand on many of these
topics in later chapters.
The 3D Printing Process
The 3D printing process, also called a workflow, involves taking a three-dimensional model and making it
ready for print. This is a multistep process starting with a special form of the model and software to break
the model into instructions the printer can use to make the object. The following provides an overview of the
process, classifying each of the steps by software type. I discuss each in greater detail in Chapter 3.
An object is formed using computer-aided design (CAD) software. The object is exported in a file format
that contains the Standard Tessellation Language (STL) for defining a 3D object with triangulated surfaces
and vertices (called an .stl file).
The resulting .stl file is split or sliced into layers, and a machine-level instruction file is created
(called a .gcode file) using computer-aided manufacturing (CAM) software. The file contains instructions
for controlling the axes, direction of travel, temperature of the hot end, and more. In addition, each layer is
constructed as a map of traces (paths for the extruded filament) for filling in the object outline and interior.
The printer uses its own software (firmware) to read the machine-level file and print the object one
layer at a time. This software also supports operations for setting up and tuning the printer.
Now that you understand how a 3D printer puts the filament together to form an object, let’s take a look
at how the object is printed by the printer.
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Chapter 1 ■ IntroduCtIon to delta 3d prInters
How an Object Is Printed
It is important to understand the process by which objects are built. Knowing how the printer creates an
object will help you understand the hardware better, as well as help you tune and maintain your printer.
That is, it will help you understand topics such as infill, shells (outer layers), and even how parts need to be
oriented for strength.
The process is called additive manufacturing3 and is used by most 3D printers available to the
consumer. Conversely, computer numeric control (CNC) machines start with a block of material and
cutaway parts to form the object. This is called subtractive manufacturing.4
Both forms of manufacturing use a Cartesian coordinate system (X, Y, and Z axes) to position the
hardware to execute the build. Thus, the mechanical movements for 3D printing are very similar to the
mechanisms used in CNC machines. In both cases, there are three axes of movement controlled by a
computer, each capable of very high-precision movement.
Additive manufacturing has several forms or types that refer to the material used and the process used
to take the material and form the object. However, they all use the same basic steps (called a process or
workflow, as described earlier) to create the object.
The most common form of 3D printing for hobbyists and enthusiasts is called fused filament fabrication
(FFF). Since the majority of 3D printers available today for consumer purchase are FFF, I will only discuss
FFF in depth in this book. To simplify our discussion, henceforth I consider 3D printing to be synonymous
with the FFF process. In fact, all printers discussed in this book are FFF-based.
When a 3D printer creates an object, the material used to print an object comes in filament form5 on a
large spool to make it easier for the printer to draw material. The filament is then loaded into an extruder
that has two parts: one to pull the filament off the spool and push it into a heating element, and another to
heat the filament to its melting point.
The part that pulls the filament and feeds it to the heating element is called the cold end, whereas the
heating element is called the hot end. Sometimes manufacturers refer to both parts as the extruder, but
others distinguish the extruder from the hot end (but they sometimes don’t call it a cold end). Delta printers
typically separate the parts with the first part fixed to the frame and the second on the axis mechanism
(called the effector). Just one of the many nuances to 3D printing I hope to explain!
■ Tip never buy filament that isn’t on a spool or a similar orderly delivery mechanism. Improperly wound
filament can introduce a maddening number of extrusion failures.
This is where 3D printers can differ. That is, they vary slightly in the mechanism used and the materials
used to form the object. Table 1-1 lists some of the forms available, describes how the material is used to
build the object, and tells what materials can be used.
3For more information, visit http://en.wikipedia.org/wiki/3D_printing.
4Also called machining; see http://en.wikipedia.org/wiki/Machining.
5Like fishing line, or as my wife says, “fishing twine.”
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Chapter 1 ■ IntroduCtIon to delta 3d prInters
Table 1-1. Types of Additive Manufacturing
Type Build Process Materials
Filament Objects built layer by layer, where material in filament form Various plastics, wood,
is extruded from a heated nozzle. nylon, and so forth.
Wire An electron beam is used to melt the wire as it is unspooled Most metal alloys.
to form an object, layer by layer.
Granular Various processes are used to take material in a raw, Some metal alloys and
granular form using a laser, light, or electricity to fuse the thermoplastics.
granules and build the object.
Powder A reactive liquid is sprayed on a power base to form solid Plaster and similar granular
layers. Some variations use a multistep process to fuse and materials. Emerging
then bind materials. solutions can use metal.
Another form uses light or laser to cure powder to form Resin.
solid layers. Printers of this type typically use SLA/DLP
projectors for the light source.
Laminate Material is laid over the object and fused with a heated Paper, metal foil, plastic film.
roller. A laser is then used to cut out the shape.
If this sounds like nothing more than a fancy hot glue gun, you’re right! The process is very similar,
but unlike the hot glue gun that relies on human power to pump glue sticks (however inaccurately) into
the heating element, 3D printers use a computer-controlled electric motor called a stepper motor to
precisely control how much and how fast the filament is fed to the hot end. Most extruders use a direct drive
mechanism where the drive pulley is driven by the stepper motor. This allows for faster retraction to avoid
stringing (thin wisps of filament trailing the hot end).
Figure 1-1 shows a drawing of how the extrusion process works, including a pictorial representation of
the components discussed in this section.
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