Apps

Bowties.cc: Free Butterfly Key
Inlay Templates

October 27, 2026  ·  VARØ Industries
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A butterfly key is one of the nicest fixes in woodworking. A crack in a slab becomes a feature, held shut by a little hourglass of walnut or maple. Getting the key to drop snugly into its recess is the fiddly part: the router bit rounds the corners, the guide bushing shifts every edge, and the key needs just enough room for glue.

Bowties.cc does that work. It's a free browser tool: design the bowtie, say how you're going to cut it, and download the templates with every offset and clearance already worked out. It's the bowtie-specific sibling of Rideline, our guide-bushing template generator.

Bowties.cc showing a soft-cornered bowtie recess template with engraved label and a matching key template

A soft-cornered 3″ bowtie: recess template on the left, key template on the right.

Three Ways to Cut It

Router + Guide Bushing
A recess template for the workpiece and a key template for the contrasting stock, for any bit and bushing you own.
Brass Inlay Kit
One template. Rout the recess with the collar on and the key with it off. It checks your kit's sizes match.
Laser-Cut Keys
Cut the keys themselves on the laser, corners rounded to fit the routed recess, with kerf compensation.
Four Styles
Classic straight sides, soft rounded corners, curved sides or rounded ends, at any size or from quick 2″–6″ presets.

See the Fit Before You Cut

Bowties.cc simulates the routed recess and the finished key and lays them over your design. Anywhere they differ shows up in red, with a plain-English note: the sharp corners a 1/4″ bit can't reach, a waist too narrow for your bushing, a kit whose collar and bushing don't match. Then it checks that the key actually fits in the recess. Pick the Soft style with a corner radius at least as big as your bit's radius and the recess cuts exactly as drawn.

Bowties.cc laser mode: a recess template and four laser-cut walnut keys

Laser mode: one recess template and a sheet of keys with kerf compensation.

Sizing and Grain

The butterfly key size chart gives starting proportions from 1-1/2″ to 8″ long. Whatever the size, run the key's grain along its length so it lies across the crack, and rout the recess a third to half of the way through the slab. The how-to guide walks through the whole job, and there's a page on how inlay kits work if you have one in the drawer.

Measure your bushing and collar. Real sizes aren't always what's stamped on them, and an inlay shows every thousandth. Use the custom size fields with your caliper readings.

Free, and Nothing Leaves Your Browser

No account, no uploads, no tracking. Downloads are true-scale SVG and DXF with red cuts, blue score marks and an engraved label so you always know which bit and bushing a template was made for. Open bowties.cc and make a few.

Check out more free tools and apps at varo.industries/apps.

Frequently Asked Questions

Which way should the grain run in a butterfly key?
Along the key's length, from one wide end to the other, so the key lies across the crack. A key with its grain running across its width is weak at the narrow waist.
How deep should a bowtie inlay be?
Many woodworkers go about a third to half of the slab's thickness, often 1/4 to 1/2 inch on tabletops. Cut the key a little thicker than the recess is deep and plane it flush after the glue cures.
Why don't the corners of my bowtie fit the routed recess?
A router bit is round, so the recess's inside corners keep at least the bit's radius. Round the key's corners to match (the Soft style in Bowties.cc), use a smaller bit, or square the recess corners with a chisel.
Does Bowties.cc work with brass inlay kits?
Yes. Choose Inlay kit, enter the kit's bit, bushing and collar sizes, and it makes the single template the kit uses for both the recess and the key, and checks that the sizes follow the kit rule.
Is Bowties.cc free?
Yes. It runs in your browser with no account, nothing you make is uploaded, and the site has no analytics or tracking cookies.

Sources & References

  1. Bowties.cc — free butterfly key inlay template generator
  2. Butterfly key size chart — Bowties.cc
  3. Bowtie templates for router inlay kits — Bowties.cc
  4. Rideline — guide bushing templates for any shape