Bill of Materials

The printhead, frame, gantry, and more are all 3d printed parts. That’s what makes this printer so awesome. But for obvious reasons there are still a number of items that need to be purchased.

The official BOM is available here.

Some of the more expensive parts or more commonly asked about parts are (in no particular order):

  • Ender 2 Pro heated bed (yes, Ender 2. Not 3)
  • SKR Pico mainboard
  • Banana Pi M2 Zero
  • ~3KG of filament

I was able to purchase everything I needed off AliExpress. In the future I will post links to the companies I used but for now that’s a Patreon exclusive on Matt’s Patreon and I want to respect that.


This entire guide is a major work-in-progress, but the BOM in particular is just now being started. Make sure you reference the official BOM as well. The current revision of this guide is based on THE 100 v1.1-beta1. That means my counts for screws and heat inserts may be slightly off once v1.1-final is released. It should be very close though.

I will be updating this guide to reference v1.1-final once it is released.

Fasteners / Hardware

Screw lengths can often be interchanged with one size up or down. For example you can almost always use an m3x10 where an m3x12 is called for. The sizes listed below are what I personally recommend, but you will find people using slightly different sizes in some cases.

I have minimized different sizes as much as possible but I’d personally rather have the right size than to make something work. I will continue to minimize the different sizes if possible though.


ℹ️ M2.5 is only needed because the mounting holes on the BTT SKR Pico are M2.5. If you have another mounting solution, or you’re willing to drill out the mounting holes on the board to fit M3, then you don’t need these.

m2.5 nut12
m2.5x40 screw4


M3-sized fasteners make up the vast majority of what is needed to build the printer.

m3 heat insert158
m3 nut29
m3 washer8
m3x6 screw14
m3x10 screw40
m3x12 screw76
m3x16 screw22
m3x20 screw12
m3x25 screw19
m3x35 screw11
m3x40 screw8


M5-sized fasteners are primarily used for the belt-bearings to ride on.

m5 washer14
m5x30 screw4
m5x40 screw2


ℹ️ Weights are for PLA based on a density of 1.24 g/cm3.

Single color3.4kg (3359g)
-- OR --
Primary color (frame)1.7kg (1719g)
Accent color (connectors)285g
Other (use primary, accent, or other)1.4kg (1355g)

Ordered everything you need?! Let’s get printing!