Why Your Board Was Quoted on the Fine Pitch Route

You uploaded a board, expected the advertised price, and got a higher one. Nothing has gone wrong — the board fell outside at least one Standard manufacturing limit and was quoted on the Fine pitch route instead. This explains what that means and what you can do about it.

One limit is enough

The Standard line is a specific process with specific tolerances. A board is compared against every limit, and exceeding any single one moves the whole board to the Fine pitch route. It is not a score or an average.

That surprises people, because a design can be comfortably inside every limit but one — a single cluster of small vias, or a board a few millimetres too large — and still be routed. The reason is physical rather than commercial: the process either holds a tolerance or it does not.

What is actually measured

The values come from your Gerber and drill files, not from your design rules. In broad terms:

• Board dimensions, taken from the outline layer.
• Copper layer count.
• The narrowest trace on any copper layer.
• The tightest gap between separate copper features.
• The smallest drilled hole.
• Hole density across the board area.
• The tightest annular ring — the copper left around a hole.

The current limits for each are published on our capabilities page. They are worth reading against your own design rather than guessing which one caused it.

The one that usually causes it

In practice, fine features are the common cause — trace width and the spacing between copper. Both are frequently inherited from a design rule template that was written for a different fabricator, or for a board that was never actually manufactured.

Board size is the next most common, and it is usually deliberate rather than accidental: the design simply is bigger than the Standard panel is set up for.

Hole size and annular ring appear less often but are the ones people are most surprised by, because vias are usually left at a default that was set once and never revisited.

What is worth changing

If a single measurement is marginally outside a limit, it is often worth changing. Widening the narrowest traces, opening up spacing in one dense area, or increasing a via pad diameter are usually small edits, and they can move a board back onto the cheaper route.

If several measurements are outside, or one is far outside, it is usually not worth contorting a design to fit. The Fine pitch route exists precisely so that boards which need finer features can still be built.

What is never worth doing is loosening your design rules without changing the geometry. The measurement comes from the copper, not from the rules file.

You will be told which one

A quote that moves to the Fine pitch route names the measurement responsible and the limit it missed, so you are not left comparing tables by hand. If it is one number and a small margin, that is a clear signal the edit is worth making.

If you are not sure whether a change is worth it for your design, reply to the email that comes with your board review and ask. That conversation takes a few minutes and occasionally saves a redesign.