Every template shows its flange lines: cyan dashed lines marking the flanges where the panel is fastened to the airframe, and other structure behind the panel (sub-panels, stiffeners, the edge of a glare shield) that limits how deep an instrument can be behind them. Check an instrument's depth before placing it over one.
An instrument drawn with the room its body or guard needs behind the panel (the toggle switches, circuit breakers, switch guards and some USB chargers) shows that as a dashed outline too, so you see what will not fit before the panel is cut.
A round instrument is drawn at its panel hole's size, and where its body behind the panel is larger, that is a dashed outline around it, so two gauges set side by side leave the room the real ones need.
- Flange lines, the layers button in the tool row, shows or hides them all together. A red slash across it means they are hidden; your browser remembers the choice.
- The button is grayed on a design without any.
- They are drawn the same way on every template, cyan and dashed, whatever the template's picture used.
- They show on every Panel color, white or not, so they are there while you place instruments.
- On a colored panel, the template's holes (a control wheel's, for example) are drawn as flange lines too.
- They are never in an exported picture, nor in the picture sent with a CAD, Cut, Paint & Label request.
- Measure gives the distance from an item to the closest flange line on each side. See Measure distances on your panel.