How Big Should the Hanging Hole Be in a Laser Cut Ornament?
For a 3 mm plywood ornament, make the hanging hole 3 to 5 mm in diameter and keep at least 3 mm of material between the hole and the nearest edge. Use about 3 mm for thin twine, 4 mm for cord or hooks, and 5 to 6 mm for ribbon folded through. Our ornaments use a 4 mm hole.
It is the last small thing on the file and the first thing the customer touches. You hang the ornament on the tree, tug the ribbon, and either it glides on beautifully or the wood cracks at the top like a nutshell. The hanging hole decides which.
A hanging hole is a small circular cut-out near the top of an ornament through which a string, ribbon or hook passes. Its size depends on what goes through it and on the strength of the wood around it.
Recommended hole size by hanger type
| Hanger | Hole diameter (3 mm plywood) | Notes |
|---|---|---|
| Thin twine or thread (1 mm) | 3 mm | Tight but easy |
| Jute cord or string (2 mm) | 4 mm | Our default size |
| Metal ornament hook | 4 mm | Hook wire is usually under 1.5 mm |
| Satin ribbon (3 mm wide) | 4–5 mm | Fold flat to pass through |
| Ribbon (6 mm wide) | 6–7 mm | Needs a bigger hole and more margin |
| Leather cord (2–3 mm) | 5 mm | Allow for knots |
Our ornaments use a 4 mm hole, for example in the reindeer at 90 × 124 mm. That size fits most cords and hooks while leaving plenty of wood.
Where to put the hole
A hole in the wrong place is worse than a hole of the wrong size. Rules that work:
- Keep the margin between the hole and the edge at least equal to the plywood thickness, preferably 3 to 4 mm.
- Place the hole above the centre of mass, so the ornament hangs straight rather than tipping.
- Avoid putting the hole across the grain where the wood is thin, such as through the neck of an animal.
- Keep at least 2 mm of solid wood on each side of the hole at its narrowest point.
For a hanging hole of 4 mm, that means a tab at least 4 + 2 + 2 = 8 mm wide around it. A tiny star point that is only 6 mm wide cannot carry a 4 mm hole safely.
Kerf and hole size
The laser removes a bit of wood along the path (kerf, typically 0.1 to 0.25 mm in 3 mm plywood). For a hole, the cut falls on the line, so the finished hole is roughly one kerf larger than drawn. A 4 mm hole may come out near 4.1 to 4.25 mm. That helps with fit, but if you want a tight hole for a metal ring, draw it slightly smaller, say 3.8 mm, and test. See what kerf is.
Pro tip: cut three test holes at 3, 4 and 5 mm into scrap and try your real cord. The quickest decision you will ever make.
Worked example
You make 3 mm plywood reindeer and sell them with jute twine of about 2 mm. Pick a 4 mm hole. The hole sits in the middle of the head between the antlers, 6 mm below the top edge, leaving a 4 mm wall above the hole (6 minus the 2 mm radius). The ornament weighs a few grams and hangs level. If a buyer wants a ribbon 6 mm wide, move to a 6 mm hole and increase the wall above to 4 mm of wood, which means moving the centre 1 mm lower: 7 mm from the top edge.
Common mistake: a hole smaller than the plywood is thick, such as 2 mm in 3 mm ply. The laser leaves a funnel-shaped burn and the hole closes with char, so even thin thread will not pass. Never go below the material thickness without testing.
Practical checks before you cut a batch
| Check | Target |
|---|---|
| Cord passes with a knot | Yes, without forcing |
| Wall around the hole | 2 mm or more |
| Ornament hangs level | Hole above centre of mass |
| Edge of hole is clean | Sand lightly or use air assist |
| Char inside hole | Wipe with a cloth or light sanding |
Plywood sheets that are painted or stained lose a little hole size, because coatings add thickness. If you finish after cutting, allow an extra 0.2 to 0.3 mm.
Next step
Open a file from the Christmas ornament category, measure its hole, and decide whether your cord needs a bigger one. If you resize ornaments, remember that holes scale with the file: see how to scale laser files. For your first complete project, try your first laser project: a Christmas ornament.
Questions and answers
What size hanging hole should I use for a 3 mm plywood ornament?
3 to 5 mm, with 4 mm a good all-round choice for twine, cord and hooks. Use 6 to 7 mm for ribbon 6 mm wide.
How far from the edge should the hole be?
At least as far as the plywood is thick, preferably 3 to 4 mm of wood between the hole and the edge.
Does kerf change the hole size?
Slightly. The laser cuts on the line, so the finished hole is about one kerf larger, typically 0.1 to 0.25 mm.
Why did my ornament crack at the hanging hole?
Most likely the wall around the hole was too thin, under 2 mm, or the hole sat across the grain in a narrow section.
Does the hole size change when I scale the file?
Yes. A 4 mm hole at 150% becomes 6 mm. Redraw it to the size your hanger needs.
Should the hole be centred at the top?
Put it above the centre of mass, usually on the vertical centreline, so the ornament hangs straight.