This 3D printable filament joiner tool is designed to allow reliable joining of two pieces of filament so that leftover material can be reused. The jig holds the filament in alignment while the ends are heated and pressed together inside a PTFE guide tube, producing a straight and consistent join suitable for feeding back into a 3D printer.

The tool is intended to reduce wasted filament, extend the usable life of partial spools, and avoid unnecessary filament changes during long prints.

Features

Allows joining of two filament ends with controlled alignmentDesigned for use with PTFE guide tubing to maintain straight joinsDesk clamp design keeps the jig stable during useTop clamp helps maintain filament tension while completing the joinCompatible with common filament materials such as PLA, PETG, and ABSSimple mechanical design suitable for FDM printingIncludes a detailed instructional PDF for assembly and operation

Technical Details

Designed for standard FDM 3D printingRecommended materials:Main body and clamp: PLA or PETGFlexible grip insert: TPU

Hardware required (not included):

1 × 50 mm PTFE tube (4 mm outer diameter, 2 mm inner diameter)1 × M5 × 30 mm thumb screw bolt1 × M6 × 20 mm nylon bolt or equivalent1 × 4 mm × 12 mm flange screw1 × M5 rivnut

The PTFE tube should have a slit cut along its length to allow easy removal after joining the filament.

Files Included

3 STL files:Main bodyTop clampFlexible grip component

1 PDF instruction guide explaining assembly and filament joining process.

Usage Notes

Print the components using standard FDM settings appropriate for the chosen materials.Assemble the jig using the specified hardware and follow the included PDF instructions.

To join filament, insert the slit PTFE tube into the guide channel, feed the filament ends into the tube, heat the filament ends, and press them together inside the tube while the jig maintains alignment.