How do I correctly align the brake disc with the callipers when replacing my quick-release wheel? My bike's front wheel is quick-release (QR), but the rear has a traditional skewer (because of the hub gears). It also has disc brakes, and as you'd expect, there isn't a lot of clearance between the brake pads and the discs.

When removing and replacing the wheels, I find it easy to make sure the rear wheel is free of the pads: when I close one eye and peer through the brake calliper assembly, I can see light either side of the disc. If I can't see light on one side, I loosen the nut on that side of the axle, and tighten the other one. Then when I spin the wheel, it spins freely.

But when I replace the front wheel with the QR skewer, I find that as tightening the QR pulls the forks together slightly, I often end up with the disc touching one of the pads. I then have to undo the QR, loosen or tighten it by half a turn or so, and then try again. Usually it takes me two or three tries to get it right, and I don't think the QR is really tight enough when the wheel is free to rotate.

Is there an easier way to get it lined up? In case it makes a difference, the pads and discs are about 6 months old and I use them every day in all weathers.
Most modern disc brakes (mechanical or hydraulic) can be aligned by loosening the caliper from the frame or fork, grabbing the brake hard, and re-securing the bolts. Then once you let go of the brake, it should be centered. 

Not ideal for the trail, but easy in the garage.