How cellos are made

A good cello takes 200 to 300 hours of hand work, plus weeks of waiting for glue and varnish to dry.

stations: 10
things upstream: 47
raw sources: 13
steps from the ground: 8

The short version

A cello is built over an internal mold. Ribs are heated and bent, then glued to corner blocks. A maple back and a spruce top are carved from thick slabs with gouges and planes. The top gets a bass bar, edges get purfling, a neck and scroll are carved from maple, and many coats of varnish finish it.

Build the mold

A mold made to the exact inside measurements of the cello shapes and holds the body while it is glued. Templates for the back and top plates are made at the same time.
Bend the ribs

Six ribs are cut and bent with a heating iron and a bending strap, which softens the wood just enough to bend without cracking. They are glued to the corner and end blocks and clamped to the mold.

Goes in
Lumber Adhesive
Carve the plates

Back and top plates start about 25 millimeters thick and are hand-carved with gouges and planes into arches. The arch matters for both strength and sound. Spruce is easier and quicker to shape than harder maple.

Goes in
Lumber
Close the back

The back plate is glued to the ribs and clamped. The f-holes are drawn on the top and cut out.

Goes in
Adhesive
Glue the bass bar and top

A bass bar is cut to fit under the top and glued in. Together with the sound post it supports string tension of roughly 80 pounds and carries vibration to the surface. The top is then glued on.

Goes in
Adhesive
Inlay the purfling

A channel is cut around the edges of the top and back and filled with purfling, a decorative inlay that also helps stop cracks from spreading.
Carve the neck and scroll

The neck, pegbox and scroll are roughly cut from one block of maple and hand-carved with planes, chisels and scrapers, then fitted to the body.

Goes in
Lumber
Sun-darken and varnish

The bare cello sits in sunlight or a light box for a week or more, and is exposed to ammonia fumes to darken the wood further. Then comes several coats of the luthier's own varnish, with light sanding between them.
Fit the fingerboard and post

The fingerboard is attached with weak hide glue so that it can be removed for repairs. A spruce sound post is cut to match the arching and set between the top and back.

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Adhesive
String it

The nut, bridge and strings go on, and the nut's string grooves must be cut at precise spacing and angles for the cello to play in tune.

Goes in
Steel wire

End of the lineCello

Worth repeating

The varnish on a cello neck is left off on purpose, so a player's thumb doesn't wear it unevenly.
Some cellos are made from aluminum or carbon fiber instead of wood.
The back plate is usually made from two blocks of wood, carefully matched so that the flame and grain align.