C64 and making doublesided floppies

Chuck Guzis wrote: It doesn't. The C64 flippy disks worked just fine. The 1541 didn't care about the index hole at all. The floppies that didn't work were early generations of SS/DD 5.25". Early on, they really were single sided and could fail. Later on, even the ones labeled SS/DD were actually DS/DD because it was easier to manufacture DS/DD's and label them as both. I used a normal hole puncher to make these. Didn't bother with a special square one. Worked just fine as long as you aligned the hole properly. You shouldn't use DS/HD floppies with the 1541 as the r/w head doesn't have the proper power to handle to coercivity of high density disks. (Not sure if that would be ok with the 1571's.) The only real worry was dirt since you're now spinning the disk backwards when you put it in upside down. As long as it spins in only one direction, dirt tends to stick to the inner cladding or whatever it's called. When you put them in upside down, they spin backwards releasing some of the dirt back onto the cookie. In real life however, the only time I had any problems it was due to magnetic interference or bending when not too careful.