3D Printing: "Warts and All"

I'm fairly new to 3D printing. My current 3D printer is a Printrbot Simple. Yes, it has been heavily modified with a focus on "micro " printing, but it is still an entry level printer at best.

As a "noob" I did my homework. I read the blogs. I prepaired myself / set my expectations low. In light of all this, I decided to do a "warts and all" tutorial on how to build your own 3D printed Smartwatch, from the moment you pry it off the print bed.

We'll start with a pile of plastic:


And end with this:


Prep Step 1: Printing configurations

There are a lot of variations in the current consumer FDM 3D Printers, with lots differences in capabilities and quality. I currently only own one printer, a heavily modified PrintrBot Simple, wooden version. I got a Simple primarily to learn. Modifications were part of my learning process. I also wanted a machine tuned for detailed work. The OSWatch is a example of detailed work. The walls get as thin as .6 mm in some places. A stock 3D printer generally extrudes a .4 - .5 mm wide line in the X/Y direction, with layers being as thin as .1 mm in the Z. This matters in small projects. A .4 mm extrusion line printing a wall that is .6mm wide will cause 2 problems:

1.) the wall will at best be 2 layers thick, which opens the possibility for gaps / holes
2.) The wall may not be as accurate as desired, either thinner or thicker, depending on slicing.

I currently extrude .2 mm wide on the X/Y and .1 mm on the Z. This has given me decent detailed results, but it does greatly increase the build time. That's part of why I added a bowden extruder, since that lets you crank up the extrusion speed (i.e. reduced print times) All things considered, it should still be possible to print the models with a wider nozzle, but the printing will probably take some more tuning and tweaking (But isn't that always the case)


Prep Step 2: How to print?

I experimented with various model placements, with my main goal being to avoid scaffolding. A drawback I have experienced with a more detail oriented machine is that it cannot achieve as steep angles without scaffolding and scaffolding in general requires more trial and error / post print cleanup. I have included some variation models, which you can pick & choose from depending on your printer / results.


Prep Step 3: Download Parts

oswatch_strap_holder.stl (x2)

Decision / Experimentation Time:

You have 2 options for the bottom. You can accept heavy scaffolding, but print the base as one part, or you can use no scaffolding and print the base as 2 parts, that will have to be joined together precisely. I eventually dealt with the scaffolding, but you can try both.


Optional Parts:
oswatch_rubber_seal.stl (optional)
Optional for increased sealing, requires a Flex Filament

oswatch_spacer.stl (optional)
Another optional part, used to provide more room inside the watch if needed


Prep Step 4: Tools & Parts


Soldering iron
Rough Sandpaper - 3M 332U 100 Aluminum oxide
fine Sandpaper - 3M 216U P400
Super Glue
Clear Spray Paint - test before use
Target Color Spray Paint - Optional
Solder helper (claw thing)

4x Flat head Phillips Machine screw 4-40 thread, 5/8 inch length
Part 91771A112

4x Undersized Machine Screw Hex Nut, 4-40 Thread
Part 90730A005


Prep Step 5: Alert Indicators

I have gone through a this build many times, incompletely. I would be doing fine, and then I would make a small mistake, and ruin a part / parts. This is extreemly frustrating, especially if you have put an hour or so of work in a part you ruined in 5 seconds. When you see the messag below


When you see one of these, pay attention to the note! It's a really important item, and not following it will probably ruin your progress.

If you run into any other lessons learned the hard way, e-mail me and I'll add a indicator.


Now Let's get started!

About DoNothingBox

DoNothingBox LLC founded in 2013 by Jonathan Cook as a base to launch his passions, and showcase his portfolio. It's also to entity that holds any copyrights.

Updated May 16, 2014

3D Printing Steps