Chamfer

Use Chamfer to cut a flat bevel where a fillet would round. Select one or more edges, press H, and type a distance.

One distance, and only one

The popover has two rows: the edges, and the Distance. Distance is the setback from the edge, the same on both faces. There is no second distance, no angle, and no reference face to choose.

Everything else works exactly as Fillet describes: one distance for every edge in the feature, all edges on one body, above zero and up to 100 mm, the same edge picker that opens holding the edges the chamfer already has, and an edge that vanishes dropped with a warning on the step while the rest carry on.

Choosing a chamfer over a fillet

For a printed part the choice is usually about the machine rather than the look.

A chamfer on the bottom edge prints; a fillet on it does not. A round at the base of a wall starts as a near-horizontal overhang against the plate, which the first layers cannot support. A 45° bevel is exactly the overhang most printers handle without help. Look at almost any printed bracket: the underside is chamfered and the top is rounded.

A chamfer is a lead-in. A bevel around a hole or on the end of a peg guides the mating part in. A fillet in the same place does the opposite. It leaves material where the other part needs to start.

A fillet is for stress. Where a part will be loaded, a round spreads the load and a sharp internal corner concentrates it. Round the inside corners that carry force, and bevel the outside ones you have to print or fit.

When it fails

The failure is the same as a fillet's, diagnosed the same way, and so is the fix. Nothing is promised before the attempt — there is no maximum printed under the Distance field — but a distance that does not fit comes back with the largest one that does:

A 2 mm chamfer does not fit here — the largest that fits is 1.4 mm

That number comes from re-running the same chamfer at halved distances until the kernel accepts one, and it sits under the field as a one-click Use 1.4 mm. Bevels that each fit on their own but run into each other say exactly that, and an edge whose two faces are already tangent says there is nothing there to cut.

When the diagnosis cannot be run, the generic message survives:

Chamfer geometry failed — common causes: distance too large, edges interfere, edges not connectable. Try a smaller distance or fewer edges.

Halve the distance and rebuild. If it still fails, take the stubborn edges out of the selection and bevel them in a second chamfer.

See also

• Fillet: a round instead of a bevel
• Cut and Push Face: cutting a bevel a chamfer cannot make