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Why You Should Build It Yourself

It didn’t take much to convince me, once I saw the vision behind RepRap–the Replicable Rapid-prototyper It was a robot that was intended to clone itself! What a simple, but hugely extendable vision!

I bought into the idea immediately.

I saw that I needed a 3D-printer to print the parts I was determined to design in order to build my own machine that would clone itself. Being retired, I was concerned about cost as well as capability of the machine I would buy. But I also realized that putting together a kit would help me understand the underpinnings of the technology (while saving some money).

So, a kit it was. After looking around, I decided on a small, inexpensive, 3D-printer kit. It was a Printrbot Jr in kit form. It had a working envelope of only 135x115x100mm (5″x4.5″x4″). From previous experience though, I knew that the vast majority of parts made were small parts. I felt I could design within this constraint. I got the 3D-printer and soon had it working. Umm, not so well though. At first, it was delivering undefined blobs of plastic. No matter. A little work with calibrating the machine and all was well.

“Well and good,” you say, “but engineers and technicians don’t put kits together. They design and make the parts. Then put them together. They go deeper.”

Ahh. Good point. (A little plug here). What offers are the designed parts. You make them (3D-print them from the files provided), buy the other precision parts that are spelled out in the Bill-of-Materials, then put them all together. Directly to the point above, the idea is to develop a fuller range of deeper skills. You’ll be assembling the mechanical components, wiring up and testing the electronics, configuring and loading the firmware and software, and making those “tweaks” needed to give yourself a finely-tuned machine–and a lot of pride in what you accomplished. The “HowTo” documentation for all this is complete–and a point of pride for Finix Systems.

Back to the story.

3D-design software was the next challenge. Fortunately, there was a good choice in OpenSCAD–a free-for-the-download 3D-CAD program A particularly good first programming language (technically, a modeling language) in that you can visually see the object you just programmed. OpenSCAD converts the parts designed right into the files you can then print.

As part design progresses, a designer will see avenues to make a feature do more than one thing. In seeing the detail of how the parts go together, S/he might also see how to eliminate some parts, and how to combine others to give a more elegant design. This trait of insight->invention is true of all the disciplines common to robotics and 3D-printing–mechanics, electronics, programming.

Once the first prototype is built, a designer will likely see easy-to-do extensions, making the machine ever more capable.

An engineer does more than sit behind a desk noodling. S/he spends time deciding on the parts needed, then more time on the Internet looking for and buying those parts. Even deciding between competing suppliers.

Speaking of the Internet: when you have problems–and even very experienced techs and engineers have problems, the Internet is your best friend. A solid method to searching and quickly finding solutions is a great skill to develop.

A budding technician or engineer will be developing the skills needed to go further. And there is always further. Wiring, assembling, soldering, measuring with both mechanical and electrical measurement tools are skills developed to last a lifetime. Even selecting new tools for value vs. cost is a valuable skill.

Helping you to build useful and modern skills is what we do. Give us a try at

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Ideas Going Into the Visible Robot

The idea:
The basic idea behind the “Visible Robot” is to create a simple extensible 3-axis robot that a parent and child can build together to learn about the fascinating world of robotics.

The idea comes from the days following one Christmas when my father watched me assemble a model Ford V8 called the “Visible V8,” answering my questions along the way. From this experience, as a pre-teen, I learned how an internal combustion engine worked.

For the more advanced, this 3-axis machine can be built upon and extended into a light-duty desktop manufacturing workstation. The Visible 3Bot and the Finix Auto Tool-Changer—ATC  (a beta product) gives peeks into what might be done in terms of extending the Visible Robot’s ecosystem.

             “The 21 st century belongs to the skilled and the creative.”

Some will find this design wanting in one way or another and will design and build improvements to it. I encourage them to do this, using the same or similar licensing terms. I sincerely hope they’ll become the giants who provide their shoulders for others to stand on.

Ideas going into the design:

Open Source: The machine is intended as a base device that can be hacked, extended and improved. By its licensing (, extensions can be made and given (or even sold) back to the community.

Open: True to the model of the “Visible-V8” of my childhood, the Visible Robot’s workings are clearly visible via its open-box mechanical architecture and glass bed. The viewer can see all the components and how they work together.

A Workcell vs. a Robot: Beyond simple visibility, the openness of the design allows various other devices to be placed alongside and within its perimeters. These auxiliary devices will complement the machine in giving it increased capabilities. Examples: a conveyor bringing parts to the machine, a carousel offering other tools to use, etc.

Scalable: The simple cartesian (box-like) design allows for sizing the device to accommodate the needs of the working space available and the workpieces to be manufactured. Changes to the lengths of the frame members (and possibly their diameters) and the angles of the stiffening supports are all that’s required.

Extendable: The design was intended from the outset to be a basis for a tabletop “workcell”—a small manufacturing center with associated programmable tools, sensors and feeders. The form-factor chosen is that of a gantry-style cartesian-coordinate structure. The open-sided design is intended to allow for enrichment of its ecosystem. It allows for extending the system to include new functionalities, such as tool-presentation devices, cutting bit exchange, vision inspection, new gripper types, and 4th and 5th degree-of-freedom joints.

Multiple gantries can be driven along the same common axis to give additional productivity and capability. Think of the robot as a “one-armed paper-hanger” and how this might be helped with a second or third ‘arm.’ (See

Easy to Print: A simple, small-footprint 3D printer is all that’s needed to print the parts of this design. All the 3D printed parts can be printed in non-toxic, non-fuming PLA. The parts to the working prototypes were all printed in my small home office/computer room which has no outside ventilation. No support material is required for any of the parts.

Easy to Assemble: The base and gantry are fastened with standard 5/16” and 3/8” nuts. M3 (3mm) screws are used throughout for non-structural component fastening. The printed components themselves contain holes serving as lock-nuts for fastening. (For those in metric environments, 8mm and 10mm can be substituted easily for the 5/16” and 3/8” parts).

Easy to Align: With all corners of an axis fixed, a precision machine can be difficult to align due to very slight differences in shaft parallelism. Allowing a small amount of ‘slop’ in just one corner retains the precision of the device—the ‘reference datum’ is on the opposing shaft to the ‘sloppy’ one—yet allows much easier alignment.

Easy to Wire: Easily obtained ribbon cable, with attached Dupont connectors can be used for the wiring. These are made to be easily pulled apart to give as many wires as needed for connection to the motors, micro-switches, etc.

Designed to be Built Anywhere: The base design includes precision parts such as linear bearings, leadscrews and anti- backlash nuts, which give the machine its resolution. Coupling and framing those precision parts is a combination of 3D-printed plastic parts and  inexpensive threaded rod and nuts and bolts that can be bought at any hardware store.

Conceptually, aside from the necessary precision components, the intent was that the machine could be built in the developing world as easily as in the developed.

Value-oriented: The combination of precision parts where necessary, but otherwise inexpensive components leads to the ideal of a “value-oriented” system. The Visible Robot is not targeted at the “low end.” Instead, it is targeted as a foundation for a useful light-duty desktop machine tool, capable of performing tasks—albeit at lower precision, lower speed and smaller tool and part size—that one would see done in a machine shop.

Minimal Tools Required: To accommodate building the machine in the home, whether the home is a sprawling home in the suburbs or a hut in the jungle, it is designed to be assembled by hand, with minimal tools. Fastening is by nuts and bolts rather than by weldments. A tiny home or neighborhood-based 3D printer can print the needed connecting parts. The parts printed for the machine were all done on a Printrbot Jr., with a workspace of 5” x 4.5” x 4” (130mm x 115mm x 100mm).

Nuts are typically a part of the printed component, achieving a locking of the screw similar to a lock-nut, thereby avoiding the need for extra fasteners—nuts and lock washers.

Stiffness: Mechanically, a measure of stiffness is achieved using inexpensive threaded-rod (T-rod) set at angles bracing the ‘X’ and ‘Y’ axes.

To avoid reliance on an inherently imprecise plastic extrusion process, metal-to-metal contact is used where it can be. The ‘X’ and ‘Y’ shafts, gantry shafts and ends of the threaded-rod frame all contact one another.

The ‘Z’ axis has three shafts to help resist moments (side forces).

Cable-routing: Care has been taken with the design of cabling routing, such that it is not free to interfere with the travel of any axis or the workpiece.

Easy Workbed Leveling: The bed can be leveled using the four thumbwheel leveling dials—one at each corner. A hex-head (Allen) bolt and spring mechanism is used to set the “Home” position of the Z-axis (typically, on a 3D-printer, the nozzle position just above the workbed).

Open Source: Source code for the parts is available as well as the compiled “.STL” files, such as one would find on Thingiverse, Pinshape, Shapeways, or in other parts repositories, some of which are listed here: Nearly three years of work—trial and error—has gone into the design, therefore, the code is being provided “Free as in speech,” rather than as “Free as in beer,” for what I consider a fair and relatively nominal charge.

Acknowledgements: This design would not have been possible without others who have gone before and provided the Arduino platform, robot-control ‘shields’ for it, design software, robot control software, slicing software, etc. In this design and its implementation I’ve used the Arduino, Printrboard, RAMPS, Megatronics, OpenSCAD, Repetier Firmware, Repetier Host, Curaengine and Slic3r, and the vision of RepRap—the self-replicating robot. I thank and am indebted to the developers and maintainers of these stalwarts of the Free and Open Source Software and Hardware world.

For hacking the design of the plastic parts, a free and open-source program (OpenSCAD) available at is used. (BTW: a nice first-entry into the world of programming languages in that one can visualize the outcome of the program as a shape that one’s just created)!

RepetierFirmware (not included) is suggested as the firmware base for the ArduinoMega/RAMPS control board.

RepetierHost (not included) is suggested as the robot controller.

RepetierFirmware and RepetierHost are both available for free download at

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Shared memories

Among the most memorable things a child will experience is time spent with a parent or close relative in a bonding adventure. The adventure might be as quiet as a hike in a forest or around a lake. It might be as exhilarating as a ride down a zip-line. It might also be doing something challenging or intellectually stimulating—like climbing a mountain or or making something together. The operative word is “together.”

This is a personal recall on “memories and bonding”, I offer no research to back me up. 😉 Feel free to plug in your own memories as you read.

As I think back and try to pick out what made my own experiences memorable and bonding to another person, it seems that most of those times I was engaging with just one person, or a very small number of people—always people close to me. The experience was usually new to me, whether or not it was new to them. Though sometimes repeated and ongoing events are remembered fondly—like the summer Sunday picnics the family used to take.

Another quality that made things memorable was investment. There was an investment of time, of energy, of money sometimes, in the activity. Both parties gave something, though in my experience, usually the adult gave more 😉

Having said that, there were times when the adult was just a welcome spectator—as when my father gave up a Saturday of overtime work to come and watch me at a swimming meet. I had been to many swimming meets, but when my father showed up to one, it was a big deal!

Sometimes the “watcher” roles switched and the child was the onlooker—as when as a young child I was taken to watch my mother as an actress in a play, “The Mikado.” “Hey ! That’s my mom up there!”

Indispensable to the memory was focus on the togetherness of the activity.

All of us have done things that started out great, with generous intent, but just turned out wrong. Maybe we laughed at them as they happened. Maybe it took some time before we saw the humor in the minor disaster—the cake that collapsed in the middle that was supposed to be a Mother’s Day surprise, for example.

I often spent time with my father in his workshop. He would explain the tools and methods he was using and talk about different materials and how they were used. As our old Pontiac station-wagon was beginning to rust out, I decided to surprise my dad and fix a growing rust spot on the front fender. He was at work when I got out the tin-snips, sandpaper and wire brush and got to work. Getting down to bare metal took little time. It looked great—all shiny. All the rust was gone. The fender was ready to be repaired.

I was applying the fiberglass patch. What a mess! Fiberglass resin dripped down the fender. The fiberglass was wet and sticky and slumped into the hole I’d widened. I tried to fill the slump with more resin. It slumped and slid further. I added more hardener. This stopped the slide, but made the slump permanent. My father came home. He was a serious man. I worried he was going to see the mess I made and be angry. He looked at it nonchalantly. No expression at all, at first. “Oh, oh,” I thought. His face began to crack as he tried to hide his emotion. He couldn’t. He broke into a raucous laugh, slapped me on the back, and said “Well, you tried.”

At that, we both laughed.

So that’s my short take on what makes a fond memory. Yours may be different. It has elements of a new adventure, or an ongoing activity done together. It’s done one-on-one or very-few-on-one. An investment, at least of time or effort, is made by both. Failures are made into bonding experiences by laughter and showing love.

Finix Systems — — offers 3D-printable robot designs and complementary product designs aimed at practical education in robotics and 3D-printing.

Together, parent and child–or students in a small classroom or lab–can learn the basics of robotics. The resulting machine can then be used to make things, even to clone parts of itself!

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The Robots are Coming!

We read about it all the time. The article title might be something like: “The Robots are coming! The Robots are coming!” Usually coming as a mixture of technical wonder and a dose of foreboding.

We read that even entry-level jobs are in danger of being lost to automation: food kiosks, self-service checkout, automated freight delivery, self-driving taxis even!

It’s not difficult to imagine a dystopia where even entry-level jobs become automated–the ones most of us older folks used to climb the job ladder. Where high-paying jobs are scarce.

So here’s the question:

 “Who will prosper as robots do more of the work?”

Looking at history for clues, it’s not hard to see who advanced with each new age of innovation. The answer to that “Who will thrive … ?” question has been:

 “Those who came to understand the technology that was brewing.”

As a kid, it was exciting for me to learn how a car engine worked. I learned by sitting at the kitchen table and putting together a model of a Ford V8 engine, with my father sitting beside me and answering my questions. The model was called “The Visible V8.”

Through the clear plastic “engine block,” I could see how the pistons moved, how they turned the crankshaft, that turned the camshafts, that operated the valves, that brought in the fuel and removed the exhaust. The battery-powered “starter” motor caused all these to function together.

As teens and young adults, my generation pounced on every new innovation with the automobile (even though looking back, some of these were clearly marketing-driven and pretty lame). A knowledge of simple mechanics allowed an understanding of more complex mechanisms to develop. Fiddling with the car’s electrical parts was followed with a crude understanding of electronics. For some of us, electronics training helped develop that understanding further.

For years there’s been a convergence of the different skills needed to build machines to do useful things–and for these same machines to be re-programmed to do different useful things. The field was “robotics.” Another term, “mechatronics” has come into use. Boiled down to basics, mechatronics (or robotics) is the study and practical application of mechanics, electronics and programming.

Skills developed in these areas will provide a basis for the creative mind to invent–and to prosper.

The “Visible Robot” was created on the model of the “Visible V8.” Like the Visible V8, the components are all visible and easily understandable.

Beyond the simple movements of the model engine that was the Visible V8, the Visible Robot was designed–after serving as a hands-on teaching vehicle while being built–for a life as a useful programmable tool that could be put to use making parts; as a vehicle for the development of new tools and techniques; or even as a simple, inexpensive testbed for research.

Together, parent and child–or students in a small classroom or lab–can learn the basics of robotics. The resultant machine can then be used to make things, even to clone parts of itself!

Finix Systems — — offers 3D-printable robot designs and complementary product designs aimed at practical education in robotics and 3D-printing.

The designs come as downloadable files to be printed in plastic on a 3D-printer. These are files similar to the ones you would find on or at The designs come with full documentation with many photos and an illustrated bill-of-materials (BOM). All the documents are available for viewing on the above website. For those wishing to delve further into the design, the OpenSCAD source-code is available for all the parts. The source-code is well documented to aid the beginning programmer.

As Finix Systems products are downloadable files, not included are the metal shafting and rods, motors, leadscrews, leadnuts and fasteners. These (listed in the BOM with suggestions as to suppliers) would be purchased separately.

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Leveling the Visible Robot’s Workbed

A critical operation in terms of getting good work out of the machine is leveling the Visible Robot’s working platform (also called its workbed, or “bed” for short). This should be leveled not in terms of level with the earth (although that might be nice), but with respect to the tools it will use. If the robot is being used as a 3D-printer, for example, the tool we care about is the extruder. In particular, we want the tip of the extruder nozzle to represent the ‘Z-Home’ position. We achieve this by setting the Z-min microswitch to “click” when we are almost touching the bed on all four corners. The distance between the tip of the nozzle and the bed surface is the working height for the first layer of plastic—a height at which the extruder can lay down filament that’s both close enough to widen the first layer so that it easily sticks to the surface during the print, but not so close that it causes the plastic to bulge out parallel to the trace being laid, where it may well then be pulled up off the bed when the extruder comes by for a parallel trace. I use a height of .004” (0.1mm) for work with PLA plastic.

Here’s how to do it.

BTW: This technique should work for any cartesian-style (box-like) 3D-printer having a Z-minimum sensor setting and levelers for each of the four corners. Though the measurements will likely differ.

  1. Set all leveling dial nuts such that they can be turned to elevate or reduce the height of the platform equally. This means that a nut that is 1/4” (6.35mm) tall will be able to elevate a corner of the platform about 1/8” (3.175mm). Likewise, it will be able to reduce the height 1/8”. Taller nuts—double size—may be easier to achive leveling with.
  2. Move the extruder tip up and away from the platform using the Manual Control of your control software (e.g., Repetier Host, Cura, etc.). This is so that it won’t crash into the bed if the bed isn’t level along the extruder’s travel.
  3. Test that your Z-min microswitch is working by raising the extruder, say 40mm above the bed.

    a) Press the ‘Home Z” control on your software, while keeping one finger on your power supply switch in order to turn it off should this be needed.

    b) With your other hand, manually toggle the microswitch as it descends before it comes close to the bed.

    c) On toggling the microswitch, the downward motion should stop. If it doesn’t, and continues to descend, switch off the power supply to stop it. If you had to switch off the power supply, fix what’s wrong with the microswitch circuit. This is usually a bad connection either at the microswitch itself (bad solder joint?) or at the Visible Robot’s control board (e.g., RAMPS, Megatronics, Printrboard, etc.), but could also simply be a bad microswitch.

  4. If you haven’t tested each of the axes previously, use this same technique to ensure all the microswitches are working. Toggling any microswitch should cause the robot to stop moving in that direction.
  5. Home the ‘X’ axis. (This control is the little “Home” icon with an “X” in it).
  6. Home the ‘Y’ axis.
  7. These last two steps will put the robot at [0, 0, ?] [Xposition, Yposition, Zposition] (if you’ve set the “Home” position to Xminimum and Yminimum).
  8. Raise or lower the Z axis so that the nozzle tip is about 10mm (0.4”) above the surface of the bed.
  9. Using the Manual Control of your control software, jog the Z-axis downward in 1mm increments until you can see just a tiny bit of space between the tip and the surface or until it is stopped because the microswitch was triggered.
  10. If the tip would touch the bed before the Z-readout of the controlling software indicates 0.00, you’ll need to lower the microswitch in order to raise the nozzle. One complete turn (360deg.) will move the microswitch 0.5mm. (This is the pitch measurement of the M3—3mm—screw that’s used for the Zmin adjustment).

    a) First, raise the Z-axis so that the microswitch is completely open (Normally Open, or ‘NO’). 10mm should do it.

    b) Turn the Zmin adjustment screw (it sits beside the Z-axis motor) counter-clockwise (CCW). This allows the spring to push the Zmin microswitch downward.

  11. On the other hand, if the microswitch was triggered before the nozzle came close to the bed as you performed Step #9:

    a) Raise the Z-axis to allow the microswitch to come to its open position. As noted in Step #10a above, about 10mm is good.

    b) Turn the Zmin adjustment screw clockwise (CW) to raise the microswitch—thereby allowing the Z-axis to descend lower before the switch is triggered.

  12. Use a .1mm or .004” feeler gauge or a piece of printer paper to judge the height of the nozzle above the workbed. If you can just barely feel the gauge or the piece of paper touching both nozzle and bed as you move your gauge back and forth, you’ve set a good working height. (It happens that 20# printer paper is .1mm (.004”) thick). Of course, if you’re planning to set your nozzle to work at a different height, substitute gauge dimensions as needed.
  13. If the distance between the nozzle tip and bed isn’t quite right yet, go back to Steps #8 to #12 until it’s correct. Remember that proper leveling is a real key to getting good prints. Take the time to get it right and you’ll save a lot of frustration that comes with botched prints.
  14. From here on, you won’t touch the Zmin adjustment screw unless you exceed the limits of what the leveling dial nuts allow. Instead, you’ll be using the Visible Robot’s leveling dials. These rotate a nut around a ¼-20 bolt (¼ inch diameter, with 20 threads-per-inch (TPI)) to change the height at each corner. Twenty threads per inch yields a thread pitch—the linear distance gained in one revolution—of 0.05”. So, for every revolution of the leveling dial the height will change by 0.05”, or 1.27mm.

    If you think of the leveling dial as a clock, moving the dial from twelve o’clock to one o’clock will change the height of the bed -0.1mm. Moving it from twelve o’clock to eleven o’clock will raise it 0.1mm.

  15. Raise the Z-axis by 10mm. Then move it to one of the other corners.
  16. Repeat the steps #9 to #13, but instead of using the Zmin adjustment screw, change the height of the bed with the leveling dial for that corner.
  17. Raise the Z-axis by 10mm. Go to a third corner that’s not been leveled.
  18. Repeat Steps #9 to #13, again using the leveling dials. Then go to Step #19
  19. Raise the Z-axis by 10mm. Go to the last corner.
  20. Repeat Steps #9 to #13, as before, using the leveling dials to set the height.

You’re DONE. Treat yourself to an ice cream sundae—or a banana split if you’re really hungry.

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The Need for Tech Literacy in Education

There’s a critical need for education suited to the way we live and work in a modern, technologically advanced society.

I humbly suggest some goals for a system that prepares students to not just live–but thrive–in a world infused with tech. A world that’s increasingly competitive.

A first goal would be for the student to have the answers to the “How does this work?” question of the modern gadgets we use today. A second would be to have a solid foundation for understanding those things we’ll use in the coming decades.

Up until roughly 1970, much–if not most–practical learning was done outside of the schools. A kid would work to buy an old car and learn to fix it. Another would get a hand-me-down radio that wasn’t working, find that a vacuum tube was burnt out, fix it, and have a source of music.

Unfortunately, inside the schools, practical learning like that done in wood, metal and auto “shops” was given to those students thought “not headed to university.” The prevailing mindset in the teaching profession seemed to be that knowing how things worked, being able to craft things, and having the ability to repair them, was to be left to those too “unbright” to move into careers where the emphasis was on “thinking.”

As an unskilled kid earning my first paychecks on the “entry-level rungs” of the job market, I had a newspaper route, washed dishes in a restaurant, and worked summers as a “beater operator” in a paper mill.

Those jobs are all gone or going. Automation in some form has replaced or is replacing them. Today, we read that restaurants are using automated kiosks. Soon the fast-food jobs three generations used as stepping stones may also be largely automated.

The basis for automation is technology. A society believing it can maintain its standard of living without understanding those things on which that standard of living depends, while letting others supply those things, can only be described as naive.

A critical goal of modern education in this technical age should be to prepare the student with an understanding of the basics of technology. It’s not necessary that a student be able to design a gizmo, but she should know roughly how the gizmo works. If it’s a cellphone, a playstation, or WiFi router, she should know about frequency transmission, the network that provides it, and have a basic understanding of electronics. If it’s an automated tool or a robot, an understanding of how sensors are used in its control, how it moves to position. If a solar or other energy system: how energy is transferred, stored, and used. I think that since kids are “wired for language” at a very early age, some programming language should be taught while they are still “wired” that way. At the latest, kids should be programming by the time they leave grammar school.

There’s a story about two people walking in the forest, where they’re threatened by a bear. They start sprinting away from the bear. Panting hard, one says to the other “We’ll never outrun the bear.” The other says (insightfully): “I just have to outrun you.” It’s not necessary for a person–or a society–to be the best-of-the-best. It’s only necessary for that person–or society–to be ahead of the competition.

Automation is a fact of life. Those who come to “own it” in terms of knowledge and capability should prosper. offers 3D-printable robot designs and complementary product designs aimed at practical education in “mechatronics”–the new buzzword covering a field that includes mechanical, electronics, and programming (aka robotics). The designs come as files to be printed in plastic on a 3D-printer, with full documentation with many photos and an illustrated bill-of-materials (BOM). Not included are the metal shafting and rods, motors, leadscrews, leadnuts and fasteners. These (included in the BOM with suggestions as to suppliers) would be purchased separately.

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The Visible Robot — What’s the Total Cost?

Visible Robot with Finix Extruder and E3D hotend

With any purchase, cost is a prime consideration. So, what can a buyer of the Visible Robot expect the as-built cost to be?

The following should give you a good idea.

Shipping cost is not included. Nor is the cost of fasteners, nor threaded rod. These items are easily purchased at a local hardware store. Neither are taxes included.

To 3D-print the plastic parts, expect to use about 1kg (2.2lbs) of plastic filament. This will cost in the neighborhood of $15-30. If you are printing indoors, consider buying PLA filament (non-toxic, no smell, eco-friendly, re-cyclable).

The controller, power supply and precision parts are where the biggest costs are.

I’ve shopped for and bought parts online in the USA, China, and Europe. My go-to online sources for general parts are:,, and For specific parts I like—leadscrews and leadnuts; and RobotDigg—stepper motors, linear bearings, finished wiring. Bear in mind that shipping costs can add a not-insignificant amount to the total cost and to the delay between the time the part is ordered, and when it’s received.

Power supply (PSU)
Although my first 3D-printer (a Printrbot Jr.) was powered by an AC/DC adapter, I opted for an ATX (desktop PC) power supply in the range of 400W. Figure to spend between $30 and $45, although you can spend considerably more. Remember though, that these ATX power supplies are quite advanced and provide functionality specific to a desktop PC that you don’t really require. Because of the standardization and volume of production of this PSU, it gives very good value for the money.

Controller boards
For a controller, I’ve used the Printrboard, ArduinoMega 2560 with RAMPS1.4, and Megatronics V3 boards. The best buy is probably the ArduinoMega 2560 with RAMPS—although the Megatronics V3 board has somewhat more capability. This board-set—as does the Megatronics V3 board—uses small daughter-boards to control the stepper motors. Buying the set will cost between $13 and $35, depending on where you shop. For the most part, I’ve bought these parts from China. Not knowing the Chinese vendors or their reputations, when I use AliExpress, I only buy from 4.5-to-5.0 star suppliers.

You’ll need three motors for the Visible Robot. Here are a few with prices.
RobotDigg NEMA17-48: $8.90 ea. – very common in 3D-printing
RobotDigg NEMA17-60: $11.50 ea. – my preference in NEMA17 motors
RobotDigg NEMA23-56: $19.00 ea. – my preference in NEMA23 motors
RobotDigg NEMA23-76: $21.00 ea. – a really beefy NEMA23 motor.

The robot / 3D-printer uses hardened, chromed shafting for its “ways” of moving along X, Y, and Z axes. Two each are used on ‘X’ and ‘Y’axes: 10mm x 500mm, and 12mm x 800, respectively. Three 8mm x 330mm are used for the ‘Z’ axis.

At any significant distance from China, shipping can make a huge difference in the total price. Also, I’ve had some shipping damage as well as shafts that have later developed rust. The problems, I suspect, are that they weren’t chrome plated well-enough, or contained insufficient chrome to prevent rust.

The advantage in buying from Chinese suppliers is that shafting is quite cheap. The disadvantage is that the shafts can be sub-par in quality, and can be shipped with inadequate packaging. I have had both very good, and bad experiences with shafting. Unfortunately, I didn’t record which shafts came from which vendor nor kept them separate, so I’m unable to give a recommendation except for “ex caveat emptor.

8mm x 330mm: $3.50 To $6.50 ea.     From China
10mm x 500mm: $10.50 to $12.50 ea.        “       “
12mm x 800mm: from $4.70 to $15.00 ea. “       “

Linear bearings are what glides the robot / 3D-printer over the shafts. Needed are six 8mm bearings, four 10mm bearings, and four 12mm bearings. RobotDigg offers both “standard” quality bearings and “Quality” bearings. “Quality” is a new offering. I’ve just used the “standard” type. My costs have been in between the two.

8mm standard linear bearing (LM8UU): $0.40 ea. ( x 6 =$2.40)
10mm standard linear bearing (LM10UU): $0.50 ea. ( x 4 =$2.00)
12mm standard linear bearing (LM12UU): $0.50 ea. ( x 4 =$2.00)

8mm “Quality” linear bearing (QLM8UU): $0.90 ea. ( x 6 =$3.60)
10mm “Quality” linear bearing (QLM10UU): $1.00 ea. ( x 4 =$4.00)
12mm “Quality” linear bearing (QLM12UU): $1.00 ea. ( x 4 =$4.00)

Leadscrews and leadnuts
I’ve used exclusively Roton leadscrews and plastic anti-backlash leadnuts. I buy the Hi-Lead ¼” – .250 (lead) stainless steel ‘X’ and ‘Y’ axis drive screws as 4 feet sections, then cut them to 18” and 30” respectively. For the ¼” – 20 (TPI) ‘Z’ axis, I also buy 4 feet sections and cut them down, but you can buy just a one-foot length.

¼” – .250 (lead) Hi-Lead stainless steel leadscrew: $15.63 / ft.
¼” – .250 (lead) Hi-Lead steel leadscrew: $10.63 / ft.
¼” – 20 (TPI) stainless steel leadscrew: $22.75 / ft.
¼” – 20 (TPI) steel leadscrew: $10.63 / ft.
¼” – .250 (lead) Hi-Lead flange anti-backlash leadnut: $21.41
¼” – .250 (lead) Hi-Lead flange leadnut: Not Available (use the above)
¼” – 20 (TPI) flange anti-backlash leadnut (plastic): $19.41
¼” – 20 (TPI) flange leadnut (plastic): $14.34

Conclusion and summary
Let’s price-out two Visible Robots: one at the very lowest price point and another more suited to higher-capacity work. The low-cost machine will use NEMA17-48 motors, steel leadscrews, “regular” leadnuts, and “standard” quality bearings and the lowest cost  parts listed above. The higher-capacity machine will use a higher quality power supply, beefier NEMA23-56 motors for ‘X’ and ‘Y’ axes, and a NEMA17-60 motor for the ‘Z’ axis. It will use stainless steel leadscrews, anti-backlash leadnuts, and “Quality” bearings. It will use the higher cost of the parts listed above.

Lowest cost machine    Hi-capacity machine
Visible Robot file download             $39.95                       $39.95
Plastic filament                                  $15.00                       $30.00
Power supply                                    $30.00                       $45.00
ArduinoMega 2560/RAMPS            $15.00                       $35.00
NEMA17-48 motors (3)                   $26.70
NEMA17-60 motor (1)                                                       $11.50
NEMA23-56 motors (2)                                                     $38.00
8mm x 300 (hip-shoulder sept’n)       $12.00                       $24.00
8mm x 330mm (3)                             $10.50                       $19.50
10mm x 500mm (2)                           $21.00                       $25.00
12mm x 800mm (2)                           $9.00                         $30.00
Linear bearings
8mm (6)                                             $2.40                         $3.60
10mm (4)                                           $2.00                         $4.00
12mm (4)                                           $2.00                         $4.00
Leadscrews and leadnuts
¼” – .250 Hi-Lead ‘X’ & ‘Y’              $42.52                       $62.52
¼“ – 20 ‘Z’                                          $10.63                      $22.75
¼“ – .250 leadnuts (2) ‘X’ & ‘Y’         $42.82                       $42.82
¼“ – 20 leadnut ‘Z’                             $14.34                       $19.41

Totals                                                $295.86                   $457.05

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Economics, Politics, Demographics and Desktop Manufacturing

Is it just coincidence that economic systems, political systems, and demographics seem to follow capabilities in the spread of knowledge and the means of production?

For eons before the Industrial Revolution the means of production was “by-hand.” Fabrication—whether it was clothes to be worn, a vessel to carry food or water, a shovel, a spear or a bow to convert the bounty of nature to food—was fashioned by hand. The economic system was a reflection of this. “The pie was only so big.” Its size was determined by the number of contributors in the system. A society thrived or diminished based on its productive population and its extent. To protect and extend the society, armies were needed. The armies were led by kings.

The economic system of the times was mercantilism. The political system, feudal. The king gave the society protection, and increased—when he could—its extent. In return, the people gave the king’s local vassal a portion of their production. The vassal, was committed to serve the king when called to.

People lived in the towns to trade, but a good deal more lived outside the towns—near the sources of food and raw materials for products needed to trade with.

With the coming of the Industrial Revolution, production was no longer tied to what one could output with one’s own hands. In particular, the steam engine allowed metals to be taken from the ground in quantities far larger than a team of workers could produce. It allowed for fields to be harvested with far fewer workers as well. It also allowed for canals to be dug and for boats on these canals to be powered to bring raw materials to the new factories and bring the food to feed the factory’s workers and family.

Unlike a team of miners or gatherers, building a factory required huge outlays of money—capital. While some of the new factories were built with capital supplied by the nobles, others were built by giving shares in the new enterprise in return for the capital required to build them.

The economic system was capitalism. In simplest terms, capitalism is a method of funding a new factory.

The invention of the steam engine, mining driller and the harvester were not without disruption, though. Displaced farm workers and miners, without work in their fields of endeavor, began to drift into the towns to find work in the factories. Towns grew into cities.

Only a couple of centuries had passed since the invention of the movable-type printing press. In truth, this had been invented centuries before in the East, but due to those languages pictographic written vocabularies, the production of typeset was far more difficult. The alphabetic construction of the Western languages lent advantage to the wide distribution of reading material.

With this new type of printing press, knowledge flourished as it never could before. Ideas could be spread and shared among those who could read. Reading, once a skill possessed by few—the nobility, some of the merchants, and the clergy—became a sought-after skill for those aspiring to advance themselves.

Disruption occurred with this invention as well. The once monolithic Christian church was rent into several churches competing for followers—and fighting for station alongside the king. A scientific and artistic Renaissance saw the spread of knowledge and ideas. New political and economic ideas—shy and muted at first—were spread by pamphleteers.

Because production was no longer limited by what a worker could produce with his or her own hands, the “pie” was able to expand and became ever-bigger as more and newer productive tools were brought into play. And with the increased number and capability of these tools the cities continued to grow, and the country areas continued to depopulate.

The upshot of the combination of the spread of information and ideas and the new capabilities brought by the Industrial Revolution was a diminuation of the role of the king and the nobility. Though the slippage wasn’t abrupt. A new middle class arose of those who traded in the new goods, manned the machines, the boats, the trains, managed the factory workers, and accounted for their pay and output. These people had less dependency on the nobility and more on the new markets that were being created.

To the extent that nobility participated in the new markets, they prospered. Where they didn’t, their role in society diminished.

In close concert with the Industrial Revolution came a period of questioning called “The Enlightenment,” where the roles of nobility and the people were “on the table” for discussion.

Republican and democratic forms began to take hold as they hadn’t since early Rome and Greece.

With any system, though, disruption has two sides. As the cities grew, a once largely self-sufficient population grew dependent on work in the factories. The competition for jobs and lack of skills in the people caused wages to be depressed. Labor unions were formed to try to get a better deal for the worker—sometimes succeeding, sometimes just being another racket to siphon off money from them.

In terms of prosperity though, society was better off than it had been before. Material goods were more available to the common person. In political terms, leaders were now elected in many places.

The twentieth century saw further advances: the most disruptive of which might arguably be the inventions of the automobile, giving people greater freedom to travel and the vacuum tube followed by the transistor, yielding new methods of communication and computation. The transistor had two unique properties when compared to its predecessor: 1) it was scalable, and 2) it could be combined with other transistors using the same medium.The applicability of the transistor to a vast array of market solutions in computation and communication especially created a global reach for information and ideas, setting the stage for yet another revolution.

In the latter years of the 20th century, a non-market phenomenon called the free and open-source software movement occurred. Later, the free and open-source hardware movement joined it. The result of these two movements was that, among other things, tools for design and designs themselves became freely available over the Internet.

Though available since the late 20th century as products for industrial use, by the first few years of the 21st century CNC machines and 3D-printers saw an evolution to the desktop at a price a householder could afford. The uptake by hobbiests was strong. With this acceptance came the rapid introduction of new materials available for their use.

Could it be that we are seeing a fourth wave of industrial revolution?

With design tools for electronics, programming and mechanical devices freely available, and an ever-increasing number of materials likewise available, might a significant fraction of the things we use be again “home-made?” Or at least be made and traded locally?

Might they be custom-made for the buyer?

We wear clothes with a stiching fine enough that yesterday’s nobility might envy. Maybe in a few years clothes bought off-the-rack will be what only the poorest of the poor would wear. 3D print your shoes? Why not? “Just let me scan your feet—ah! Fallen arch? No problem!” the newly high-tech shoemaker says, “Your new shoes will fit your feet perfectly! They’ll be ready this afternoon.”

Design teams composed of people with similar product visions but located far apart, could produce product designs that could then be downloaded and printed, machined or sewn in the local neighborhood—or even in the home.

While some products will still require large expensive factories—semiconductors and automobiles, for example—other, less complex products could increasingly be made in the home or in small local workshops.

With the need to be close to work in a marketplace or a factory removed, will the cities depopulate and the countryside see an increase of people choosing to live a less stressed-out, less dependent, more satisfying life?

Maybe. Time will tell, but the seeds of this new industrial revolution have already sprouted.

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The Visible Robot — A Gentle Introduction

The Visible Robot is a simple machine that can move the tool it carries in 3-dimensions. The tool could be a 3D-printing extruder, a drill, a camera, etc. It is controlled by a program running on a microcontroller.

It can be thought of as the base machine onto which a plastic-melting extruder can be fastened to form the mechanical basis of a 3D-printer.

The 3D-printer works by following a programmed path on a flat bed and extruding plastic along that path, forming a layer. The extruder then moves up a notch and starts extruding a second layer on top of the first. Then a third, and a fourth, etc., until the part being made (called the “workpiece” in manufacturing jargon) is finished. Each layer is thin, but still much thicker than a layer of ink on paper that a computer printer prints out.

The 3Dprinter is somewhat like a video cartoon, where each hand-drawn picture is slightly different from the one before it and the one after it. When the cartoon is played, it seems to show the drawn characters in motion. With the 3D-printer, the individual layers—like each of the cartoon pictures—is slightly different from the one below it and the one above. As they are stacked on top of one another, unique parts can be created. A look at or can give an idea of the variety of parts that can be made.

The role of the Visible Robot in a 3D-printer application is to move the extruder nozzle to each point along the path. The role of the extruder nozzle is to heat and extrude the plastic.

Another potential use of the Visible Robot is as what’s called a computer-numerically-controlled (CNC) machine. When fitted with appropriate tools, A CNC machine can drill holes in a pattern that’s programmed, turn screws, rout or mill wood or plastic, or carry a camera to scan an image in 3D or record via photo or video an operation that’s taking place.

The limit to the jobs it can do is simply the physical limits of the space it can reach (its “working envelope”) and the imagination (and pocketbook) of the implementor.

The essence of the plain vanilla Visible Robot is that it moves anywhere within a 3-dimensional space according to program. It is a platform onto which tools can be mounted to do many interesting things.

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Some Thoughts on Making

Welcome to the “Maker” movement.

Mankind’s traditions in making—in fabrication—are strong and deep-rooted.
From the earliest days when mankind walked the planet, he was a maker. We see it in the tools uncovered from archeological sites of lives lived tens of thousands of years ago. Whether piercing tools for hunting or sewing, grinding tools for preparing meals, chopping tools for building, vessels for carrying water and grain, or digging tools for farming, our ancestors made and used them all.

Then, as now, among the most respected professions, I’m certain, was the tool maker—the maker of things that allowed others to go about their business—whether it was as a hunter, a clothes-maker, a builder, or a cook.

Today’s maker has tools available that have been refined over thousands of generations: the knife, the hammer, the awl. Though some of the tools we’re familiar with were invented only in the last few decades—the portable drill, the computer, the computer numerically controlled (CNC) machine, the robot. The truth is, we stand on the shoulders of the giants that went before.

There’s something immensely satisfying from making things. Maybe it’s ingrained in our genetics. Maybe it’s “what we’re inclined to do” as humans. I don’t question that there are other soul-satisfying endeavors—healing the sick, creating artwork, getting lost in song, or cooking the to-die-for meal.

It isn’t a competition. It’s a choice of which skills you wish to develop.

As the great American scientist, entreprenuer, and statesman Benjamin Franklin said: “labor at something you love and you’ll never work a day in your life.”

“The mission before you, should you decide to accept it …” is to build a computer-controlled desktop device that will move about in 3-dimensions and can be extended in many ways to do any number of useful jobs. Along the way, you’ll delve into mechanics, electronics and programming and reach new levels of understanding of each of them.

The type of machine you’ll build—a robot—is used in manufacturing, in food-preparation, in the arts, in medicine, and in science. If you choose to go further, the skills you’ll learn in building and working with this machine will serve as a solid foundation for whatever you care to create.

May your journey be safe, fruitful and, above all, a happy one!