Hey everyone! This is Mark III of my wrist-mounted disc launcher series. The Mark III Wrist-Mounted Disc Launcher is a fully 3D-printed , four-disc launcher with a removable cartridge and satisfying quick-eject mechanism. Recommended materials: Print the launcher in PLA or PLA+ only . Other materials may behave differently in the launch and return spring, snap-fit, and moving components and are not recommended unless you are prepared to test and tune them yourself. Recommendations for the LAUNCH SPRING (Part #2) : ✅ PLA ❌ Matte PLA ❌ Silk PLA Prepare before assembly: Flush cutters or side cutters Spare 1.75 mm filament for hinge and pivot pins Small amount of lubricant Preferably silicone dry lubricant spray , plastic-safe lithium grease , or another lubricant confirmed to be compatible with plastics Basic cleanup tools for removing supports or excess material BUILD WITH ME: IMPORTANT NOTE: REMOVE THESE BUILT-IN SUPPORTS BEFORE ASSEMBLY: Link to the ASSEMBLY VIDEO : Best practices: - Before firing, lightly press the trigger to make sure the discs are feeding freely. If anything feels stuck, stop and check the mechanism rather than forcing it. - After each shot, let your fingers come off the trigger cleanly so the return mechanism can reset quickly. CORRECT DISC ORIENTATION Make sure that the the disc is exactly how it appears on the image when you load it in. FIRING TECHNIQUE Make sure your hand is turned back when you launch a disc! Questions, build photos, modifications, and feedback, feel free to reach out! THANK YOU to everyone who has followed this project, tested previous versions, shared feedback, posted builds, and supported its development from Mk-I to Mk-II. A large part of the Mark III exists because of YOU. Version History Mk-III v1.0 — Initial Release Released: August 17, 2026 ✅ 4-disc removable cartridge ✅ Quick-eject cartridge system ✅ Fully printed return mechanism ✅ Orientation-independent disc retention/feed system ✅ Improved pusher and firing geometry A1 Mini Profile Released: August 18, 2026 ✅ A1 Mini-compatible print profile for Mk-III v1.0 Mk-III v1.1 — Reliability Update / Testing Released: August 21, 2026 ✅ Stronger cartridge locking geometry ✅ Revised disc retaining/feed clips ✅ Reduced launch-spring infill for testing ✅ Revised test profile targeting reported jamming and incomplete ejection Here’s a ready-to-paste MakerWorld description: Mk-III v1.2 — Cartridge and Return Mechanism Update This update focuses primarily on improving reliability, simplifying assembly, and making the first printing experience more consistent across different printers. What changed Completely redesigned the return mechanism. The previous four-part spiral spring and rack-and-pinion assembly has been replaced with a much simpler compression-spring system. Updated the main launcher body and added built-in supports designed to be removed easily after printing. Revised the cartridge’s launch-spring geometry to reduce stiffness and make firing more reliable. Improved how tightly the cartridge snaps onto the launcher while retaining the satisfying quick-eject action. Added a second upper disc retainer to help advance the discs more consistently. Restyled the cartridge toward the “Brand New Day” web-shooter aesthetic. The upper retainer visually resembles the wiring seen on the movie design while also serving a functional purpose. Added a printable universal pin for the pinned joints. Builders no longer need to cut spare filament from a spool for hinge and locking pins. Adjusted pin-hole tolerances to work more consistently with the new printed pins and across different printers. Important tradeoff The softer launch-spring geometry may produce slightly less power and a shorter disc-travel distance than the previous version. I believe a more reliable and accessible first experience is preferable to maximizing power with a spring that may be too stiff for other users’ prints. Community confirmation requested Please let me know how the following perform after printing v1.2: Firing reliability and spring stiffness Cartridge retention during repeated use Disc feeding and final-disc ejection Return-mechanism assembly and operation Printed-pin fit and hole tolerances Ease of removing the built-in supports These changes are intended to address the reported issues, but I will continue adjusting the design based on real-world prints and community feedback. (description last updated: September 20, 2026)
Spidey Disc Launcher Mark-III (Quick-Eject)
by MechBrick. · original on MakerWorld ↗
♥ 3.8k⬇ 3.9k🖨 5.0k prints
Print profiles
Soft Spring (Replacement) 0.2mm layer, 2 walls, 25% infill
⏱ 22m · 4 g · 1 material(s)
Prints on: P1P 0.4, H2C 0.4, H2D Pro 0.4, A1 mini 0.4, X1E 0.4, A1 0.4, X1 0.4, X1 Carbon 0.4, H2S 0.4, P2S 0.4, X2D 0.4, A2L 0.4, P1S 0.4, H2D 0.4PLA
Not in stock
A1 MINI (Ver 1.2.7) (9-25-2026)
⏱ 5h 55m · 76 g · 1 material(s)
Prints on: A1 mini 0.4, P1S 0.4, X1 Carbon 0.4, X1 0.4, X2D 0.4, X1E 0.4, P2S 0.4, H2D 0.4, H2S 0.4, H2C 0.4, A1 0.4, P1P 0.4, A2L 0.4, H2D Pro 0.4PLA
Not in stock
LATEST (Ver. 1.2.7) (9-25-2026)
⏱ 6h 25m · 91 g · 1 material(s)
Prints on: P1P 0.4, H2C 0.4, H2D Pro 0.4, X1E 0.4, A1 0.4, X1 0.4, X1 Carbon 0.4, H2S 0.4, P2S 0.4, X2D 0.4, A2L 0.4, P1S 0.4, H2D 0.4PLA
Not printable on our printers
TPU Strap Clips
⏱ 19m · 2 g · 1 material(s)
Prints on: P1S 0.4, P1P 0.4, H2S 0.4, X2D 0.4, X1 0.4, A1 mini 0.4, P2S 0.4, H2C 0.4, A1 0.4, H2D Pro 0.4, X1 Carbon 0.4, A2L 0.4, X1E 0.4, H2D 0.4PLA
Not in stock