4 layers69 × 70 mm
2 layers14.5 × 25 mm
Tailplug
RedBigz/xt-16Modular CoreXY 3D Printer with a focus on repairability.
- Size
- 14.5 × 25 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 6
- Nets
- 7
- Pads
- 17
- Tracks, vias
- 14, 0
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 15 Jul 2025
- Updated
- 9 Aug 2026
Overview
Tailplug is an open-source printed circuit board by RedBigz, from the RedBigz/xt-1 repository on GitHub. It is a 2-layer board of 14.5 × 25 mm with 6 parts on 7 nets, routed with 14 tracks and 0 vias.
It belongs with the robots and motor control boards of this library.
README
README.mdIMPORTANT
- The JST PH connectors from the D-plugs to the supp. board need to have reverse connectors!
XT-1
A modular CoreXY 3D Printer with a focus on repairability.
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Who I am and why I made this
Hi, I'm May, a 15-year-old programmer and hardware enthusiast from Australia. I have spent the past few weeks developing a custom 3D printer based on the CoreXY motion system that allows for custom component bays to be inserted on the toolhead. I made this dovetail plug (D-plug) system to mimic the concept of Framework's laptop expansion bays. I believe expansion bays largely simplify repairs performed by consumers and allows for greater self-expression through custom designs that can be attached to the toolhead.
What is this?
The XT-1 is a custom CoreXY 3D printer with two custom D-plug (as defined above) bays to transmit UART and 5V & 24V PWM signals for things such as:
- Accelerometers (not ADXL as they're SPI)
- Laser Diodes
- Fans
Here are some basic statistics for the printer:
- 2 D-plug bays
- 2WD CoreXY System
- 180x180x160 build volume
- ~360x360x420 external dimensions
Gallery
CAD Model
Supplementary Board
D-Plug
Building
CAD Models
To export parts, open the model in OnShape here (I would suggest plugging in your computer before downloading, the models are hundreds of megs and just rendering them has crashed my desktop RX 7800XT over 10 times when rendering the full assembly)
To find the assembly in .STEP format, check the asm folder in this repo.
Wiring Diagram
Quick BOM
Quick Note: This BOM is made largely for Hack Club's Highway grant program and prices reference the sale price I am able to purchase each product at (as @ 29/07/2025) in AUD (with a AUD -> USD exchange rate of $0.66 per A$1).
| Manufacturer | Item | Size | Qty | Units | Unit Cost (AUD) | Cost (AUD) | Cost (USD) | Link |
|---|---|---|---|---|---|---|---|---|
| BIGTREETECH | BTT SKR Mini E3 V3 | - | 1 | each | 52.51 | 52.51 | 34.66 | https://www.aliexpress.com/item/1005003519869375.html |
| JINGLIN | 5/lot 4-lead NEMA 17 | - | 1 | lot | 69.39 | 69.39 | 45.80 | https://www.aliexpress.com/item/1005008510880419.html |
| 2/lot 5015 Turbo Fan | - | 1 | lot | 4.90 | 4.90 | 3.23 | https://www.aliexpress.com/item/32970914615.html | |
| JINGLIN | 2/lot 4020 Fan | - | 1 | lot | 5.09 | 5.09 | 3.36 | https://www.aliexpress.com/item/32972111881.html |
| Ancufy | NEMA 14 + 1M cable | - | 1 | each | 14.89 | 14.89 | 9.83 | https://www.aliexpress.com/item/1005006423228157.html |
| HighQ | 2/lot 2020 V-Slot Extrusions | 280mm | 2 | lot | 14.79 | 29.58 | 19.52 | https://www.aliexpress.com/item/1005007310271857.html |
| 320mm | 2 | lot | 15.89 | 31.78 | 20.97 | |||
| 360mm | 2 | lot | 16.69 | 33.38 | 22.03 | |||
| Magic Dragon | 2020 V-Slot Extrusions | 300mm | 1 | each | 8.47 | 8.47 | 5.59 | https://www.aliexpress.com/item/1005004679698586.html |
| MGN12 Linear Rail | 300mm | 1 | each | 20.39 | 20.39 | 13.46 | https://www.aliexpress.com/item/1005003696820721.html | |
| CHY CNC | 2/lot 8mm Linear Shaft (M4x8mm) | 200mm | 2 | lot | 16.29 | 32.58 | 21.50 | https://www.aliexpress.com/item/1005008854590053.html |
| SNWNYN | 2x MGN12H rails, 4x MGN Blocks | 200mm | 1 | lot | 34.59 | 34.59 | 22.83 | https://www.aliexpress.com/item/1005005966099152.html |
| 3D ManufacturinG | T8 Lead Screw + Nut | 200mm | 3 | each | 5.49 | 16.47 | 10.87 | https://www.aliexpress.com/item/1005007457419235.html |
| ElectronicModule | D20L25 Lead Screw Coupler | - | 3 | each | 2.76 | 8.28 | 5.46 | https://www.aliexpress.com/item/1005006456811778.html |
| Haldis | Gearset Kit | - | 1 | each | 21.39 | 21.39 | 14.12 | https://www.aliexpress.com/item/1005004699143725.html |
| Lerdge | Lerdge iX 180mm Hotbed (Magnetic) | - | 1 | each | 30.79 | 30.79 | 20.32 | https://www.aliexpress.com/item/1005005641707683.html |
| Good Luck Elec. Prod. | 2/lot XL4015 | 1 | lot | 6.21 | 6.21 | 4.10 | https://www.aliexpress.com/item/1005006823558141.html | |
| TLZWLA | 10/lot 01x08 2.54mm Female Header Socket | - | 1 | lot | 2.16 | 2.16 | 1.43 | https://www.aliexpress.com/item/4001198421663.html |
| 10/lot 01x20 2.54mm Female Header Socket | - | 1 | lot | 2.62 | 2.62 | 1.73 | ||
| Unnamed | GY-291 ADXL345 Module | - | 1 | each | 2.91 | 2.91 | 1.92 | https://www.aliexpress.com/item/1005007557329503.html |
| ICGOGO | 40/lot F-F DuPont Jumper Wires | 100mm | 1 | lot | 4.20 | 4.20 | 2.77 | https://www.aliexpress.com/item/1005002000655439.html |
| YouKeyi | 5/lot DRV8825 Module | - | 1 | lot | 9.99 | 9.99 | 6.59 | https://www.aliexpress.com/item/1005009321177962.html |
| USBO | IEC320 C14 Fused Switch | - | 1 | each | 13.49 | 13.49 | 8.90 | https://www.aliexpress.com/item/4001315809458.html |
| Wurth Elektronik | 860040674004 100uF 50V | D8xL12mm | 10 | each | 0.555 | 5.55 | 3.66 | https://au.mouser.com/ProductDetail/Wurth-Elektronik/860040674004 |
| NINDEJIN NINDEJIN | 50/lot M2x8mm Hex Wafer Head Screw | - | 1 | lot | 2.06 | 2.06 | 1.36 | https://www.aliexpress.com/item/1005008750192874.html |
| Don Eden | Pan Screws (PH) | 50pcs M3x5mm | 1 | lot | 2.82 | 2.82 | 1.86 | https://www.aliexpress.com/item/1005008709978631.html |
| (note, 16mm screws are in place of 15mm screws due to lack of listings) | 50pcs M3x16mm | 1 | lot | 4.29 | 4.29 | 2.83 | ||
| 50pcs M3x35mm | 1 | lot | 6.09 | 6.09 | 4.02 | |||
| 20pcs M4x8mm | 1 | lot | 3.32 | 3.32 | 2.19 | |||
| 10pcs M5x8mm | 7 | lot | 3.32 | 23.24 | 15.34 | |||
| 10pcs M5x16mm | 2 | lot | 3.90 | 7.80 | 5.15 | |||
| Countersunk Screws | 20pcs M4x5mm | 1 | lot | 3.74 | 3.74 | 2.47 | ||
| Hundred Years | Pan Screws (PH) | 50pcs M3x8mm | 1 | lot | 2.64 | 2.64 | 1.74 | https://www.aliexpress.com/item/1005006674754845.html |
| 50pcs M3x10mm | 1 | lot | 2.73 | 2.73 | 1.80 | |||
| 50pcs M3x20mm | 1 | lot | 3.55 | 3.55 | 2.34 | |||
| 50pcs M3x25mm | 1 | lot | 3.89 | 3.89 | 2.57 | |||
| 50pcs M8x50mm | 1 | lot | 8.02 | 8.02 | 5.29 | |||
| Heated Inserts | 100pcs M2L2 OD3.2mm | 1 | lot | 2.89 | 2.89 | 1.91 | https://www.aliexpress.com/item/1005006967339727.html | |
| 100pcs M3L4 OD4.2mm | 1 | lot | 2.35 | 2.35 | 1.55 | |||
| CANOT | Hex Nuts | 50pcs M3 | 1 | lot | 2.19 | 2.19 | 1.45 | https://www.aliexpress.com/item/1005007593861199.html |
| 10pcs M8 | 1 | lot | 3.00 | 3.00 | 1.98 | |||
| RTLECS | 5/lot 8P 2.54mm Pogo Pins | - | 1 | lot | 11.59 | 11.59 | 7.65 | https://www.aliexpress.com/item/4001036140528.html |
| MEAN WELL | LRS-350-24 | - | 1 | each | 55.22 | 55.22 | 36.45 | https://au.mouser.com/ProductDetail/709-LRS350-24 |
| FreeBoom | PET Expandable Cable Sleeve | 25mmx2m | 1 | each | 11.09 | 11.09 | 7.32 | https://www.aliexpress.com/item/1005009088606787.html |
| Unnamed | 100/lot M/F Spade Connectors | 16-14AWG | 1 | lot | 5.61 | 5.61 | 3.70 | https://www.aliexpress.com/item/1005009138598203.html |
| Unnamed | Black Copper Cable | 5m, 22AWG | 1 | lot | 3.01 | 3.01 | 1.99 | https://www.aliexpress.com/item/1005006647928006.html |
| 2m, 16AWG | 1 | lot | 3.68 | 3.68 | 2.43 | |||
| PeoPoly | Magneto X Lancer Melt Zone Long | - | 1 | each | 45.44 | 45.44 | 29.99 | |
| Lerdge | PEI Bed | 180x180 | 1 | each | 11.79 | 11.79 | 7.78 | https://www.aliexpress.com/item/1005005332775787.html |
| wuhushiyu | T-Nuts | M5 / 20 Series | 150 | each | 0.0676 | 10.14 | 6.69 | https://www.aliexpress.com/item/32814359094.html |
| M3 / 20 Series | 50 | each | 0.0782 | 3.91 | 2.58 | |||
| Raspberry Pi | Pi 4B (out of stock, cannot verify pricing details) | - | 1 | each | 0 | 0.00 | ||
| Pi Pico H | - | 1 | each | 8 | 8 | 5.28 | https://au.mouser.com/ProductDetail/Raspberry-Pi/SC0917 | |
| WGXCPP | 127/lot Heat Shrink Kit | - | 1 | kit | 4.09 | 4.09 | 2.70 | https://www.aliexpress.com/item/1005001787291963.html |
| ? | microSD Card (self sourced) | - | 2 | each | 0 | 0.00 | ||
| Tojiato | 4/lot GT2 Idlers W6B5 | 20T | 2 | lot | 5.89 | 11.78 | 7.77 | https://www.aliexpress.com/item/1005007557987612.html |
| 20T Smooth | 1 | lot | 5.92 | 5.92 | 3.91 | |||
| Maecoom | 3/lot GT2 Timing Pulley W6B5 | 20T | 1 | lot | 6.55 | 6.55 | 4.32 | https://www.aliexpress.com/item/1005003176136280.html |
| DFORCE Trianglelab | 6mm Timing Belt | 3000mm | 1 | each | 19.11 | 19.11 | 12.61 | https://www.aliexpress.com/item/1005006507781085.html |
| Panda Bearings | 2/lot LM8UU Bearings | - | 2 | lot | 3.73 | 7.46 | 4.92 | https://www.aliexpress.com/item/1005007070280422.html |
| [PCB] (5/lot) {JLCPCB} | Supp. Board | - | 1 | lot | 10.62 | 10.62 | 7.01 | |
| Male D-Plug | - | 1 | lot | 3.21 | 3.21 | 2.12 | ||
| Female D-Plug | - | 1 | lot | 3.21 | 3.21 | 2.12 | ||
| ADXL Connector | - | 1 | lot | 3.21 | 3.21 | 2.12 | ||
| NEWHONGHUIDA Fastener | 30/lot Dowel Pins | M5x20mm | 1 | lot | 7.38 | 7.38 | 4.87 | https://www.aliexpress.com/item/4000473863693.html |
| excellence | 20/lot JST PH2.0 8P Connector | Horizontal | 1 | lot | 3.16 | 3.16 | 2.09 | https://www.aliexpress.com/item/1005007755047389.html |
| Vertical | 1 | lot | 3.10 | 3.10 | 2.05 | |||
| Unnamed | 5/lot PH 8P Ribbon Connector (Single Head) | 800mm | 2 | lot | 8.39 | 16.78 | 11.07 | https://www.aliexpress.com/item/1005006460578382.html |
| SVALID | 10/lot 4P 24AWG JST XH-2.54 Cable | 150mm | 1 | lot | 4.19 | 4.19 | 2.77 | https://www.aliexpress.com/item/1005002376525415.html |
| alinsin | 10/lot KF120 2.54mm Terminal Block | 4P | 1 | lot | 4.42 | 4.42 | 2.92 | https://www.aliexpress.com/item/1005003179482974.html |
| 3P | 1 | lot | 3.47 | 3.47 | 2.29 | |||
| Creality | CR-Touch ABL (non-bracket) | - | 1 | kit | 38.79 | 38.79 | 25.60 | https://www.aliexpress.com/item/1005009104612536.html |
| [Filament] | 1kg PETG Black (self sourced) | 0 | 0 | |||||
| 1kg PETG Pink (self sourced) | 0 | 0 | ||||||
| Shipping | 50.77 | 33.51 | ||||||
| Subtotal | 922.93 | 609.13 | ||||||
| +10% GST | 92.29 | 60.91 | ||||||
| Total | 1015.22 | 670.05 | ||||||
| Hack Club Grant | 530.30 | 350.00 | ||||||
| Out Of Pocket | 484.91 | 320.05 |
Parts
6| Qty | Value | Footprint | References |
|---|---|---|---|
| 1 | Conn_01x06 | Connector_PinHeader_2.00mm:PinHeader_1x06_P2.00mm_Vertical | J1 |
| 1 | LOGO | LOGO | G*** |
| 1 | ~ | Connector_PinHeader_2.54mm:PinHeader_1x08_P2.54mm_Vertical | UTP1 |
The 3 most common of 6 parts.
Questions
How big is the Tailplug PCB?
It measures 14.5 × 25 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Tailplug use?
6 parts. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Tailplug KiCad files?
From the RedBigz/xt-1 repository on GitHub, at the commit this page was made from: the board is pcb/tailplug/tailplug.kicad_pcb and its schematic pcb/adxl_holder/adxl_holder.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Tailplug design in my own project?
Its repository states no licence, so its author keeps all rights: ask RedBigz before reusing the design.
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