Star of David — L-Arm Butt-Joint Calculator
6 identical L-arms. Each arm = 1 Long piece (L) + 1 Short piece (S). 30° miters create 60° butt joints.
Geometry:
Offset = W / tan(60°),
S = (L/2) − Offset,
D = 2(L + Offset).
1) Geometry Inputs
This is the strip width you rip (and the piece width).
2) Geometry Outputs
Short piece length (S)
—in
Offset
—in
Final tip-to-tip size (D)
—in
Long piece length (L)
—in
Per star cut list: 6 × L and 6 × S.
3) Batch-Cut Production Plan
Rip W-wide strips → cut ALL long pieces from long-only strips → cut ALL short pieces from short-only strips.
Pieces per strip (Long)
—pcs
Pieces per strip (Short)
—pcs
Strips per sheet capacity
—strips
Cut LONG strips
—strips
Cut SHORT strips
—strips
Sheets needed
—sheets
Auto waste %
—%
4) Cut Diagram
Schematic of the Long (L) and Short (S) pieces with 30° miter ends. Updates live and respects unit toggle.
5) L-Arm CNC / Laser Template (SVG)
Generates a 1-piece L-arm outline using your computed L, S, and W (60° joint angle). Download and import into LightBurn / Illustrator / VCarve / Fusion.