Wiggle Ruler, Wave Template for Quilting & Craft

Draw round it, cut round it, or just print the shape because you like it. A wiggle ruler, ready to print.

Files

• STL: wiggle_wave_mw.stl. Plain mesh, any slicer.

• 3MF: wiggle_wave.3mf. Bambu Studio project with my tested settings (PrusaSlicer opens the geometry).

• SCAD: wave_ruler_mw.scad. The parametric source, for any other size.

What it is for

It started as a quilting template. Lay it on fabric, draw round it with a marker, cut along the line with scissors. The outer edge is the whole product: there is no seam allowance baked in and no offset applied, so the edge you draw against is exactly the line you get.

That turns out to be a small part of what people want it for:

• a wavy border on a card, a scrapbook page or a stencil

• the outline for wiggle wall art, a wave shelf trim or a squiggle sign blank

• a guide for drawing repeating waves on anything flat

• a template for wavy-edged applique, felt, leather or paper

• a wiggle-edged plant label, luggage tag or bunting flag

If you want a wave and you do not care what it is for, set the numbers and print it. That is a legitimate use.

Need a different wave? Customise in OpenSCAD

Download the .scad file and open it in OpenSCAD (free). Every option below is in its Customizer panel.

Two wave edges, each with its own peak spacing and height, on a body you set the width and depth of. The waves are true sinusoids, not a row of scallops, so the line flows rather than scalloping in and out.

Two ways to size it. The waves and the width pull against each other, so you pick which one you fix:

• Peak spacing fixed. You set the distance between peaks on each edge and how many whole waves you want, and the width follows. Use this when the wave itself matters.

• Width fixed. You set the overall width and how many waves sit on each edge, and the peak spacing follows. Use this when it has to fit a block, a border or a print bed.

Both routes reach the same geometry from opposite ends. Entering the same shape either way produces an identical file, which I checked rather than assumed.

The rest of the knobs:

• Wave height, top and bottom: Trough to peak, per edge, so a gentle roll on one side and a tight ripple on the other

• Peak spacing or wave count: Whichever sizing mode you picked

• Waist: The narrowest band of solid material between the two waves: this decides whether it flexes under a pen

• Width and thickness: Thickness is 1/4 in (6.35 mm) by default, matching shop-bought templates

• End tabs: Flat ears at each end, so the wave starts and stops cleanly. On by default

• Hole: A hanging or finger hole near one end, or both, or neither

• Solid or open window: The window hollows the middle and leaves a frame: less filament, and you can see the fabric

• Corner radius and chamfer: The chamfer is on the top face only, for the reason below

Why it is shaped the way it is

The bottom edge is square and vertical, and the chamfer is on the top face only. If the underside is rounded, a pen tip creeps beneath the edge and you draw inside the true line, so every piece comes out slightly small.

The corner radius is clamped to the tightest crest of the wave, because corner rounding flattens any convex feature tighter than the radius. Ask for a corner bigger than the wave can carry and it gives you the biggest one that is safe, and tells you it did.

It refuses bad settings rather than printing them: a waist thin enough to hinge, a crest too tight to cut round, or a window frame wider than the material it sits in all stop with a message.

Print settings

• Material: PLA, or PETG if it will get knocked about

• Layers: 0.2 mm, or 0.12 mm for the smoothest drawing edge

• Walls: 4 to 5, because the edge is the functional surface

• Infill: 15% gyroid. The walls make the edge, so more infill only adds weight

• Supports: None, flat on the plate as oriented

• Elephant foot compensation: 0, and no first-layer chamfer. The 3MF here already has it at zero

• Wall order and seam: Outer wall first and a scarf seam, so the drawing edge stays clean and true. The 3MF here already has both

A wave ruler is long and thin, so it will usually fit a 256 mm bed diagonally even when it will not fit square.

The parameter design, the geometry decisions and the testing here are mine. The OpenSCAD was written with Claude, and every version was rendered and measured before it went up.

If it is useful, a like and a make with a photo really help. I read every comment.

Also on MakerWorld: https://makerworld.com/en/models/3259738