Order one small board from a fabrication house and you will usually still pay for a minimum panel area. The standard answer is panelization: arranging several copies of the board — or several different boards — onto a single fabrication panel, separated later by routing or V-scoring. Doing it yourself has real advantages: you control the spacing and orientation, and the panel you approve is the panel that gets built. Gerbv supports this from the command line — greatly expanded command-line functionality, including the ability to panelize boards into a single one, is documented since the 2.1.0 era, and the same command-line machinery handles its export formats. This tutorial explains how to plan a panel, how the documented command-line export options apply to producing the panel files, and how to verify the result in the viewer before anything is ordered. Gerbv is on the download page (the Linux installation guide suits command-line work particularly well), and our Gerber viewer page covers the inspection side you will need at the end.
Plan the panel before touching the command line
Panelization decisions are geometric, and they are much easier to make on paper than at a prompt. Decide how many boards go on the panel and in what arrangement — a grid of identical copies is the common case, with mixed panels for small production runs of related boards. Fix the spacing between boards: your board house publishes a minimum gap for the routed separation it supports, and the panel must respect it everywhere, not just on average. Decide whether the panel needs rails — sacrificial borders that give the assembly process something to hold — and if so, how wide they are and whether they belong in the panel data you generate or are added by the house. Note the finished panel’s overall dimensions, because that is the number you will verify afterwards. All of this is standard panel planning that applies to any tool; what Gerbv contributes is the machinery to produce the panel data from your existing Gerber and drill files once the plan exists.
What the command line gives you
Gerbv’s documented command-line surface, per its man page, is built around viewing, export and transformation. Export is selected with -x followed by the format — the supported export formats include RS-274X and drill formats for data output, plus the picture formats — and the output file is set with -o. For RS-274X and drill export, two options do the geometric work that panel building relies on: -T applies translation and rotation to the exported data, and -O sets the origin of the exported coordinates, with units expressed in inch, millimetre or mil. Those documented primitives are the honest building blocks of command-line panelization: copies of a board’s data placed at planned offsets, written out as new RS-274X and drill files. One honesty note, stated plainly because it matters at a command line: the exact invocation for a full panel build depends on the layout you planned, and this site does not print a panelize command line that the man page does not itself spell out — consult the man page on your system for the precise syntax of the build you have installed, and treat any example you find elsewhere with the same suspicion. The workflow below is the documented level, and it is enough to work with.
The workflow, at the documented level
Start from a verified single-board set: run the stack through loading and aligning the layers and confirm the set aligns before you multiply it — panelizing a misregistered board manufactures the error several times over. Export the panel data layer by layer: for each Gerber layer, produce the panel version by writing the board’s data at each planned position, using the documented translate/rotate and origin options to place copies, and do the same for the drill data so holes multiply with the copper — the commands in exporting to PDF, PNG or SVG show the same -x/-o pattern for picture output. Work in a dedicated panel folder, keep the single-board originals untouched in their own folder, and name panel files unmistakably (panel in the filename, plus the arrangement, such as the copy count) so nobody can confuse a panel file with the single-board file it came from. Repeatability is the quiet prize: once the placements are written down, re-running the same export for revision C of the board produces the same panel, updated.
Verify the panel like any other board
A generated panel is just another fabrication set, and it gets the full inspection. Open the panel files in Gerbv exactly as exported: the copies should appear in the planned grid, every layer present, drill hits multiplied in step with the pads. Then measure — measuring distances and clearances is the tool for this pass: the overall panel width and height against your plan, the spacing between adjacent boards against the board house’s minimum, and the position of a copy in the far corner, because accumulated placement errors, if they exist, show up at the greatest distance from the origin. Check the outline layer especially carefully: rails, separation paths and board edges are the panel’s mechanical definition, and an overlap between two boards’ outlines is a manufacturing problem, not a cosmetic one. If anything is off, fix the placements in your command and regenerate — never edit the generated panel files by hand, or the next revision will silently lose the correction.
When to panelize yourself — and when not to
Do it yourself when you need a specific arrangement the board house will not guess: mixed boards on one panel, your own rails and tooling holes, or a panel that must match an assembly fixture you already own. Let the house do it when the board is simple and the run is a prototype. Either way, someone should view the final panel data before production; if the house panelizes, ask for the panel files back and run them through the same Gerbv check. The panel is the thing being manufactured, so the panel — not the single board — is the thing to approve, a principle the Gerber viewer checklist states for every order.
Frequently asked questions
Does Gerbv really panelize, or is that the board house’s job?
Both are real options. Panelizing boards into a single one through the command line has been a documented Gerbv capability since the 2.1.0 era. Many designers still let the board house panelize simple boards; doing it in Gerbv gives you control of arrangement, spacing and rails.
Which documented options place the copies?
For RS-274X and drill export, the man page documents -T for translate/rotate and -O for the export origin, with units in inch, millimetre or mil; -x selects the export format and -o the output file. Check the man page on your system for the exact invocation syntax of your build.
How do I know the generated panel is correct?
View it like any fabrication set: open the panel files in Gerbv, confirm every copy and layer is present, and measure the overall panel size, the inter-board spacing and a far-corner copy’s position against your plan before ordering.