Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site sftig.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxn!mhuxm!sftig!rbt From: rbt@sftig.UUCP (R.Thomas) Newsgroups: net.micro.cpm Subject: Re: using both side of disks Message-ID: <549@sftig.UUCP> Date: Tue, 16-Jul-85 13:38:23 EDT Article-I.D.: sftig.549 Posted: Tue Jul 16 13:38:23 1985 Date-Received: Thu, 18-Jul-85 04:26:08 EDT References: <11476@brl-tgr.ARPA> Organization: AT&T Bell Laboratories, Summit, NJ Lines: 44 > > It is absolutely safe to use both sides of a disk on a 1541 disk-drive > if the disks are certified double-sided on the box, and there is a > write-protect notch cut on both side edges of the disk. If not, then > it is risky to use the uncertified side for data storage. > > If you buy a commercial software product which uses both sides of a > disk, then it is probably safe to assume that they are using the > correct kind of disk. > > > --- Andy Brown Interesting. I have *never* seen a disk with notches cut on both sides, except when I have personally known the person who cut them. Most 'double sided' software distribution disks I have seen have actually not had notches on *either* side. They must have been produced on duplicating machines that ignored the presence or absence of write protect notches. On the other hand, I have the following philosophy on 'flippy' disks -- Because of the dirt entrapment/releasing problem, it is never a good idea to use the 'back' side of a disk, unless the disk is (almost) brand new. That means that for day to day use, if you only have a single sided drive, you should only use the front side of your disks. Whether you buy disks marked 'single sided' or 'double sided' is a matter of personal preference, especially since the price difference is so small, nowadays. I buy 'double sided' disks, personally, because of the following observation -- There *is* one safe use for 'flippy' disks. That is for distributing software that is too big to fit on a single side. In that case, you are going to use a new -- fresh out of the box -- disk, so you are not worried about dirt, and the recipient is going to make a backup copy (onto *two* disks!) as soon as she gets it, then put it away and (hopefully) never have to read it again, so she is not worried about dirt either. I do enough software swapping that I find it useful to have a supply of 'double sided' disks readily available at all times. As an aside, I don't think it is possible to design a liner that will not entrap some dirt, and release it if the disk is spun the other way. That just seems like the the inevitable workings of the laws of physics to me. Enjoy! Rick Thomas ihnp4!attunix!rbt