I just acquired a Crown Graphic with an Ektar 127 lens. I can't get the shutter to open the lens. The cable mechanism seems to work and I can cock and release the shutter, but the shutter leaves do not open- am I doing something wrong? Thanks

Just a guess, but many set-and-release shutters incorporate a spring-driven ring, which is what rotates when you cock the shutter, and a concentric ring to which the blades are pivoted. That actuation ring is connected to the return spring that closes the shutter.

The driver ring has a pawl that picks up the actuation ring when the shutter is tripped, causing the blades to open. At the end of the ring's travel, the pawl toggles to free the pin, and the blades close.

If the pawl were gunked up with old dry lubricant, it might be frozen in its releasing position, so it does not engage the actuating ring at all. I hate it when that happens!

You might bring the shutter in to a camera repair shop, if there's one near you. Most of them can "clean, lubricate and adjust" an old shutter. What they cannot do is repair it if it needs a part.