THOTCON 0xC · United States · 2023

THOTCON 0xC Badge

Contra-themed laser-tag badge with custom clear-PC housing

The THOTCON 0xC badge was a Chicago electronic conference badge built around a Contra-inspired, conference-wide laser-tag game and a custom injection-molded clear polycarbonate housing. Rob Rehrig's first-hand writeup documents the badge theme, enclosure work, IR receiver/emitter layout, TIR lens work, Xometry manufacturing path, and roughly 2,000-badge production scale.

THOTCON United States Chicago Contra Laser Tag IR TIR Lens Injection Molded Polycarbonate PCB Art Electronic Badge North America

EventTHOTCON 0xC

SeriesTHOTCON

LocationChicago, Illinois / undisclosed location

CountryUnited States

People

Authors & Credits

badge housing, optics, and production writeup author

Rob Rehrig

Rehrig's project writeup preserves the 0xC badge theme, laser-tag concept, enclosure investigation, optical layout, lens work, and manufacturing decisions.

Source

badge maker and production portfolio publisher

Fourfold

Fourfold's work portfolio lists THOTCON 0xC as a complete badge package covering assembly, protective enclosure, manufacturing, and production.

Source

event and schedule publisher

THOTCON

The official THOTCON archive establishes the 2023 Chicago event, badge pickup, and badge-required party entry.

Source

injection-molding production partner

Xometry

Rehrig's writeup identifies Xometry as the injection-molding partner for the THOTCON 0xC badge housing.

Source

Why It Mattered

It closes the public THOTCON lineage gap between the 2021 0xB badge and the 2025 0xD touch-wheel badge with a source-backed record of a mechanically ambitious game badge where enclosure optics and production tooling were central to the attendee experience.

Hardware

The recovered sources document a custom PCB inside an injection-molded clear polycarbonate shell. Rehrig describes an initial two-material ABS/PC enclosure plan, LED passthrough needs, an IR receiver in the center of the badge, IR emitters to the center-left and center-right, and total-internal-reflection lens work for the laser-tag optical path.

Software & Apps

Public sources describe the core badge function as a conference-wide laser-tag game with more interactive badge behavior than prior years, but this pass did not recover a public firmware repository, schematic, BOM, Gerber archive, or full badge manual.

Lore

The badge theme drew from the NES game Contra, including a target motif inspired by the end of the first stage. Rehrig's writeup documents the production iteration from a two-piece ABS/PC enclosure toward a single clear-PC housing with Xometry as the injection-molding partner.

Lifecycle

Add-ons & Upgrades

badge game source-backed

Contra laser-tag badge game

Rehrig describes the 0xC badge theme as Contra and the core functionality as a conference-wide laser-tag game.

Compatibility: THOTCON 0xC Badge

Source

event access artifact officially documented

Badge-required party entry

The official schedule says attendees needed a 0xC badge for entry to the THOTCON 0xC party at Ravenswood Event Center.

Compatibility: THOTCON 0xC Badge

Source

mechanical enclosure source-backed

Injection-molded clear polycarbonate housing

The production path moved from a two-material ABS and PC enclosure concept to a single clear polycarbonate housing so the PCB color and LED passthrough could work within the tooling schedule.

Compatibility: THOTCON 0xC Badge

Source

optical and mechanical design source-backed

TIR lens design

Rehrig documents total-internal-reflection lens work intended to focus emitter output and shape the optical behavior needed for the laser-tag game.

Compatibility: THOTCON 0xC Badge

Source

optical interface source-backed

IR receiver and dual-emitter layout

The badge placed an IR receiver in the center and IR emitters on the center-left and center-right of the board for laser-tag interaction.

Compatibility: THOTCON 0xC Badge

Source

production workflow documented

Xometry injection-molding production path

The first-hand writeup names Xometry as the injection-molding partner and describes design-for-manufacturing tradeoffs around wall thickness, sink marks, lens geometry, and schedule pressure.

Compatibility: THOTCON 0xC Badge

Source

Operational history

Issues & Camp Impact

housing-design tradeoff note

The badge housing changed from a two-piece ABS and clear-PC concept to a single clear-polycarbonate part after injection-molding review, timeline pressure, wall-thickness concerns, sink-mark risk, and lens-geometry iteration.

The record preserves the badge as a real production artifact with mechanical and optical compromises rather than treating the enclosure as a frictionless visual shell.

Confidence: first-hand project writeup
Status: documented
Timeframe: pre-conference production
Source note: Rob Rehrig THOTCON 0xC project writeup.

missing rights-cleared image note

No THOTCON 0xC Badge image is published because the current public source trail has not been paired with a reusable original badge or artifact photo or official upstream raster render with source URL, license or permission basis, attribution, and processing notes.

The United States record remains source-backed and image-free rather than copying source-page media, documentation screenshots, event photos, social media, placeholders, or generated approximations.

Confidence: local project policy
Status: needs licensed original replacement
Timeframe: current catalogue build
Source note: badge.gallery image policy and THOTCON official 0xC schedule, Rob Rehrig project writeup, Fourfold work page, and InfoconDB event metadata source trail.

source-depth caveat note

Rob Rehrig's first-hand writeup documents the 0xC badge theme, laser-tag behavior, enclosure, optics, and production decisions, but this pass did not recover a public schematic, Gerber set, BOM, firmware repository, binary archive, or full badge manual.

The catalogue records verified event, game, mechanical, and optical facts without claiming that the complete design archive is public.

Confidence: source-backed but incomplete
Status: needs deeper archive recovery
Timeframe: current THOTCON 0xC pass
Source note: Rob Rehrig THOTCON 0xC writeup, official THOTCON 0xC schedule, Fourfold work page, and InfoconDB event metadata.

Resources

Fourfold work portfolio maker portfolio · Fourfold source identifying the THOTCON 0xC badge as a full-assembly/manufacturing project from bare PCB to polished conference-electronics product. THOTCON 0xC Electronic Conference Badge first-hand project writeup · Rob Rehrig source for the Contra theme, conference-wide laser-tag concept, custom housing design, clear polycarbonate production decision, IR receiver/emitter layout, TIR lens work, Xometry manufacturing path, and roughly 2,000-badge scale. THOTCON 0xC InfoconDB record event metadata · InfoconDB source for THOTCON 0xC dates, May 19-20, 2023, unknown-location framing, and official con-page link. THOTCON 0xC schedule official event schedule · Official THOTCON archive source for May 19-20, 2023 Chicago dates, badge/swag check-in, and badge-required party entry at Ravenswood Event Center.

Sources

Fourfold: Fourfold work portfolio Retrieved 2026-05-15 · Maker portfolio source for the 0xC badge's full assembly, manufacturing, protective-enclosure, and conference-electronics production framing. InfoconDB: THOTCON 0xC (2023) Retrieved 2026-05-15 · Event metadata source for May 19-20, 2023 dates and unknown-location context. Rob Rehrig: THOTCON 0xC Electronic Conference Badge Retrieved 2026-05-15 · First-hand badge-team source for the Contra theme, laser-tag function, enclosure and lens design, injection-molding decisions, Xometry production path, and physical-layout evidence. THOTCON: THOTCON 0xC schedule Retrieved 2026-05-15 · Official event source for the May 19-20, 2023 Chicago edition, badge pickup, and party-entry badge requirement.