Layout marks

Lay out equal divider bays

Find clear bay widths and every divider face from one reference wall, including the thickness occupied by each partition.

Equal bays need equal empty space, not equal distances between the divider edges. The partitions occupy part of the available width. This worksheet starts with the clear inside width of a box that already exists, so it does not subtract the outside walls a second time. Use it to draw a fixed-divider layout on a base or to check a layout before gluing.

How to use the result

1. Measure between the inside faces of the two outside walls at the intended divider position. Check the front and back; a tapered box cannot be corrected by spacing arithmetic.
2. Measure the actual partition stock. Enter the number of empty bays you want, which is one more than the number of partitions.
3. Mark every near face from the same inside wall. Mark the thickness on the far side of that line, then dry-fit all partitions before attaching any of them.

Worked example

With 380 mm inside width, three 12 mm dividers leave 344 mm for four bays. Each bay is 86 mm wide. The near faces are 86, 184 and 282 mm from the left inside wall. Centre marks would instead be 92, 190 and 288 mm; do not mix the two systems.

Before making

• The final bay should match the first after the last divider thickness is included.
• Test the widest item with its handling clearance, not just its nominal width.
• If a bay is too narrow, reduce the bay count or use a wider box; do not force the part during assembly.

Continue your plan

• two compartment stationery tray
• interior and clearance