PCB Panelization: V-Cut vs. Tab Routing

Choose a panel separation method around the assembly process and the finished board edge. A tightly packed array is not useful if components prevent depanelization or the separated board no longer fits its enclosure. Agree the panel with the assembler before ordering the bare boards and stencil.

Match separation to the board shape

V-cut scoring uses straight score lines to help separate boards. Tab routing removes material around the profile while leaving selected bridges to hold the boards together; perforated tabs are often called mouse bites. These approaches create different edge and handling conditions. Eurocircuits' panel guidelines describe both methods, but its dimensional rules should not be assumed to apply to another supplier.

For a rectangular board, scoring may be an option if the assembly layout allows it. For an irregular outline, routed separation may provide a more suitable contour. Present the actual geometry for review rather than selecting the method from a generic comparison alone.

Check the populated panel

Review tall connectors, components overhanging the board edge and parts near separation lines. Include the intended cutting tool or fixture in the discussion. Clearance that looks adequate on an empty board may disappear after assembly. Also identify edge areas that must be smooth enough to slide into a housing.

• Show rails, tooling holes and alignment marks on the panel drawing.
• Mark component keepouts around tabs or score lines.
• Identify which team separates the boards and at what process stage.
• State whether tab remnants need additional finishing.

Define quantity in boards and panels

For example, a six-board array and an order of ten panels represent sixty individual boards before any agreed allowances. Put both numbers on the request. A quantity field without a unit can produce an avoidable quoting error, especially when the assembly purchase order counts finished units.

Release one approved panel drawing

Give the panel a revision and use that same revision for the PCB, stencil and assembly setup. If the fabricator will create the panel, supply the single-board data plus explicit array requirements and request the proposed drawing. Do not independently create a stencil from an older panel. Confirm the complete handoff after any change to spacing, rails or orientation.

Technical reference: Eurocircuits: customer panel basics. Supplier-specific process limits in the reference are not DIYIPCB manufacturing commitments.