Fillet and Chamfer

Purpose#

Both tools work on the corner between two elements:

• Fillet inserts a tangent arc with radius R between two lines, circles or arcs and shortens or extends the elements to the tangent points.
• Chamfer replaces the corner of two lines with a bevel — with two distances D1/D2 or with angle and distance.

The elements need not touch: both tools work with the extensions.

Access#

• Ribbon: group Modify, buttons Fillet (5) and Chamfer (6).
• Classic toolbar: group Edit, buttons Fillet (6) and Chamfer (7).
• Key: U Fillet.
• Command search : Fillet, Chamfer.

Fillet#

Fillet Three steps:

1. Click the first element (1) — line, circle or arc; status line Click the 2nd element (line/circle/arc)....
2. Click the second element (2). The field R: appears, the status line reports Move the mouse → radius/sector · click = place · R+Enter = fixed radius.
3. Set radius and position (3): the mouse determines the radius (distance to the corner) and the sector — with crossing elements there are four possible corners, the one nearest to the pointer wins. A click places the arc as the preview shows it; or you type R and press Enter — then the fixed radius applies in the sector where the pointer is.

The arc is created on the active layer, the two elements are shortened or extended to the tangent points. If no arc fits — e.g. parallel lines or a radius larger than the circle — the program reports No tangent arc possible. A radius of 0 cancels.

Chamfer#

Chamfer Also three steps, here with lines only:

1. Click the first line (1) — on the side that should stay; status line Chamfer: click the 2nd line (on the side to keep).
2. Click the second line (2), also on the side that stays. The chamfer field appears with the last used values (default 5/5); the preview shows the bevel. Status line: Chamfer: enter the values + Enter, or click to confirm.
3. Enter the values and accept with Enter, ✓ OK or a click in the drawing area.

The chamfer field#

• D1, D2 — the distances of the chamfer from the corner along the first and the second line.
• ⇄ — swaps D1 and D2.
• → ∠/D — switches to the mode angle and distance: ∠ is the angle of the chamfer to the first line, D the distance along the first line; the button back is then labelled → D1/D2.
• ✂ ON / OFF — trimming: with ON the lines are shortened (or extended) to the chamfer, with OFF they stay unchanged and the bevel is added.
• ✓ OK accepts, × cancels.

The values and the mode are remembered for the next call.

Options and relations#

• Both tools stay active for the next corner; Esc ends them and removes the highlighting.
• Arc and bevel are created on the active layer.
• For a tangent arc without shortening the elements use Tangent arc.
• Fillets on circles and arcs give transitions like on slots; where two circles do not intersect, the radius must be large enough for an arc to touch both.

Related commands#

• Trim or extend one / two elements — sharp corner without arc
• Tangent arcs