They're cut manually at the factory (it's not a machine cut), so you could feasibly do it yourself. The quality of the final product will vary depending on your skill level.
Some things to know before you start:
- Don't just chop away with a utility knife. Get a short, stiff X-acto blade suitable for the task. You might want to invest in an edge bevelling tool to round off the cutout when you're finished.
- The underside of the Brooks cutout has a shallow notch around the perimeter. This allows for the topside of the cutout to flex downward when pressure is applied, and keeps the cutout edges from flaring upward.
- You'll want to lace the skirts if you make a cutout. The center "hammock" of the saddle helps to retain the tension on the leather and maintain the formed shape of the skirts. Get a good 3mm punch (either a hammered punch or a rotary style), measure and mark your punch points, and make clean holes as opposed to drilling the leather (which really is just tearing the fibers.
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"I feel like my world was classier before I found cyclocross."
- Mandi M.