Introducing... Curio128

After promising myself for months that I would set up a build log at, I'm breaking down and setting it up here.

So… this is the build log and explorations of Curio128, a Batch V MakerBot Industries Cupcake CNC, #128.



Like many Cupcakes, Curio128 has several mods. Here are a few of them:

  • Copper gilt enclosure
  • Air-blast flossing
  • Extruder PCB mounted horizontally above extruder (recently added)
  • Wipe brush
  • Tweeted build messages (disabled)
  • Heated build platform (in progress)
  • E-(asy) Stop Button (in progress)
  • CNC Music


Curio128's wood enclosure is copper gilt; all wood surfaces were primed, sized, copper leafed, and sealed. The process consumed much of the three-month build time, but the results were worth it.


Air-blast flossing

Having melt my acrylic retainer ring while generating a new thermistor table, and having only fender washers and a metal hand punch available, I created this mod that has the added benefit of flossing with a few blasts of compressed air - plastruder disassembly no longer required :)

Here are the basics of this mod:


  • A small air gap between the top retainer ring and the plastruder bottom. I used two leftover PCB standoffs, but nuts with the standard acrylic retainer will work too. You want to create enough of an air gap so that "Chippy," the filament pest, will fly away when you blast him.
  • A compressed air source with a nozzle tube. I use a compressed air can, but you can probably use any compressed air source to which you can attach a < 3mm OD tube.
  • Safety glasses so that Chippy won't end up somewhere painful

Steps 1 and 2 are only necessary if the filament is still in the Plastruder, otherwise go to step 3.

  1. Using RepG's control panel, heat the nozzle to operating temperature
  2. Once at temperature, back-out the filament (255 Reverse)
  3. After removing the filament, set the extruder motor to 255 Forward
  4. Insert an approximately 12mm x 150mm x 1mm piece of material into the air gap. The dimensions are approximate and I actually use a thin steel rule. The goal is to prevent Chippy from entering the top of the brass nozzle, so use whatever you have available that will accomplish this (cardboard, plastic, etc.).
  5. Insert compressed air tube into filament hole at top of Plastruder. Position end of tube just above pulley gear. Use short blasts of air at 5 second intervals for 30 seconds to blast Chippy away. The intervals are approximate; the motor turns at 2 RPM, and I've found that these work well. If you're lucky you'll see Chippy somewhere near your bot.
  6. Now that Chippy is gone, trim filament so that it doesn't have teeth marks on it.
  7. Finally, insert filament into Plastruder. It may be necessary to guide the filament across the air gap; use a small screwdriver or other implement to do this.
  8. Print!

This mod has reduced the TTP (time-to-print) when the filament strips from 20 minutes to 1 minute!

Plastruder mod to permit air blast flossing

E-(asy) Stop Button

I'm in the process of modding a Staples Easy Button to serve as an E-Stop switch, and to create a printable drop-in replacement for the button that can be personalized (a logo, a different word, etc.).
The mods are proving to be both easy and hard:

  • Easy - re-wiring button as a SPST NO switch
  • Hard - creating a printable personalizable button replacement. I've got an OpenSCAD file that almost works; I'll post it to thingiverse once it does work.

Through the creation of this fabject, I underwent a crash course in OpenSCAD and created a few more shapes that hopefully will be added to the shapes.scad file. I'll post my shapes.scad file to thingiverse once completed.

Wipe Brush

Having seen nophead's and Zaggo's wipe brushes, I decided to make my own. The goals were simple: good, fast, and cheap - this is usually a two-fer, but I wanted a triple.

While wandering my local little-box hardware store, I came across a disposable acid brush - perfect!

After flattening the brush handle in a file cabinet drawer - I don't have a vise - I was on my way. Once flattened, it was a matter of bending it at the correct point to elevate the bristles above the build platform, marking and punching - I do have a hand punch - a hole in the handle, and measuring and cutting the handle short. After attaching the brush via the center-right M3 build platform bolt, I flat-topped it at the right height so it wouldn't touch the Z-stage underside when the nozzle tip touched the stage.

Success, and only thirty cents poorer!

Wipe brush side viewwipe-brush-top-view.jpg
Wipe brush top viewcut-wipe-brush-top-view.jpg
Cut and punched/drilled wipe brush top viewwipe-brush-mounted-action-shot.jpg
Wipe brush in action


Curio128 was fortunate to be invited to the National Lab Day TED2010 after party. We blew many minds and had a blast doing it. You can read more here.
Curio128 @ TED2010

CNC Music

In a future post I will describe the process of creating song gcode for the Cupcake. In the meantime here's a link to a post I made on the MakerBotMusic group. The mid2cnc code is on GitHub.

Here are some songs I've created:

Los Angeles Times

Curio128 was photographed for a May 29 2010 article about - what else - 3D printing.

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