"I had read that you may double your disk's holding capacity by cutting out the proper notches on the backside of your disk's envelope. So, I grabbed my Wabash single density disks, a scissor and went snipping away. Several problems arose after trying to use the backsides on my Atari 810 disk drive. First I received many 144 errors (device done) while formatting the disk under DOS 2.0S, but successful (I thought) under DOS 1. My second problem occurred when I failed to be able to copy any files to disk. I had the speed and head pressure adjusted but still no luck."
Thomas M. Krischan
Although it is possible, in theory, to record on both sides of ordinary disks, it is not a good idea. Some disks are designed to be "double-sided" and provisions are made to thicken and strengthen the disk so that the recordings on each side will not interfere with one another. "Print-through," where the information being magnetized on one side also appears on the second side, can obviously play havoc with whatever was already on the second side.
In addition, disk surfaces are so delicate that a single cigarette ash, floating onto the disk, can render it useless. This would suggest that cutting holes in the outer envelope might deform the surface, or worse. One final drawback: attached to the inner surface of the envelope is a soft, textured fabric designed to trap any stray particles and keep them off the disk surface. Using the opposite disk side causes it to spin in the opposite direction, dislodging and redepositing any foreign matter back onto the surface.