Watch tools / Revision 3
Expansion-band stretcher
An open cleaning drum with reinforced sockets, diagonal braces, and interchangeable band-retaining inserts.
- Drum diameter
- 88.20 mm
- Overall footprint
- 96.77 × 88.20 mm
- Height
- 34 mm
- Insert sizes
- 16–20 mm (five pairs)
Assembly & reinforced socket · Model render. Select the image to enlarge.
A stronger drum for the same inserts
Revision 3 supports 23 mm of the insert spine in stepped sockets, with 26 mm rear walls and 4 mm side walls. The low front wall leaves the largest band opening clear. The diagonal frame and thicker rims carry over from Revision 2. Existing inserts still fit: only the drum needs a new print.
Choose your files
Print drum.stl upright as supplied. Use slot_inserts_16-20mm.stl for all five pairs, including 19 mm. Split the file into objects in your slicer to print just the pair you need. The editable OpenSCAD file opens as an assembly; export the separate parts for printing.
Printing & use
Start with 0.2 mm layers, four perimeters, and solid inserts. Inspect the upper-rim bridges and brace junctions in your slicer. Match the slot to the band body and wider end fittings, smooth every contact edge, and check bath clearance and filament compatibility. The 254 mm reference arc is not a guaranteed stretched band length.
Design: Beau Gosse · AI-assisted creation.
CC BY-NC-SA 4.0 · Noncommercial use, attribution, and share-alike.
Looking for the first version? Download the original band stretcher ZIP. Revision 3 above is the current design.