This is a simple but very effective 3D‑printed jig designed to help you cut a standard 25×75 mm microscope slide into three equal sections. If you do any kind of spin‑coating, perovskite work, thin‑film testing, or general lab prototyping, you already know how useful 1/3‑size slides can be—and how annoying they are to cut consistently by hand. This little rig fixes that.

The jig holds a full‑size glass slide securely in a recessed channel and provides two clean reference edges for scoring. Just place the slide in the slot, align your glass cutter along the printed guide, score the line, and snap. The result is three uniform mini‑slides with far less breakage and far more repeatability than freehand cutting.

The design is intentionally minimal: no moving parts, no hardware, no calibration. It prints quickly, uses very little filament, and is sturdy enough in PLA or PETG for routine lab use. The geometry keeps the slide flat and stable while giving your cutter a reliable straight edge to follow.

Whether you’re preparing substrates for spin‑coating, making test coupons, or just trying to get more mileage out of your glass slides, this jig makes the process faster, safer, and much more consistent.


How to Use the Jig

Insert the microscope slide into the frame, then place the base underneath. Score the slide along the guide using any standard glass scorer. Once both score lines are made, remove the base and lift the slide out of the frame.

Before cleaving, tap the scored edge of the slide over a sheet of paper placed on a flat surface. This helps remove any loose glass particles from the groove you just created.

Next, place the slide into the cleaver box with the scored side facing up. Hold the slide with one finger so it cantilevers over the small raised section inside the box. With your other hand, press down quickly and firmly. The slide should cleave cleanly along the score. Repeat the process for the second cut to produce all three sections.