meta data for this page
  •  

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Next revision		Previous revision
adv:cleaning [2022/11/20 21:55] – Initial version from discussions on Discord. flanadv:cleaning [2023/06/25 14:35] (current) – Add the success story of 7jp4-guy since it may make it easier for people to make a decision flan
Line 6: Line 6:
  
 This page gathers information from the #cleaning-tips forum on the applesaucefdc Discord. If you have questions, that is the best place to ask. This page gathers information from the #cleaning-tips forum on the applesaucefdc Discord. If you have questions, that is the best place to ask.
 +
 +----
 +
  
 ===== Overview ===== ===== Overview =====
Line 12: Line 15:
  
 ==== Structure of a floppy disk ==== ==== Structure of a floppy disk ====
 +
 +=== 8" and 5¼" ===
  
 {{ https://upload.wikimedia.org/wikipedia/commons/thumb/2/21/8-inch_floppy_disk_-_IZOT%2C_Bulgaria_-_inside.jpg/640px-8-inch_floppy_disk_-_IZOT%2C_Bulgaria_-_inside.jpg|Inside the 8-inch floppy disk}} {{ https://upload.wikimedia.org/wikipedia/commons/thumb/2/21/8-inch_floppy_disk_-_IZOT%2C_Bulgaria_-_inside.jpg/640px-8-inch_floppy_disk_-_IZOT%2C_Bulgaria_-_inside.jpg|Inside the 8-inch floppy disk}}
  
-8" and 5¼" floppies consist of a plastic disk (usually mylar) coated with a magnetic medium (sometimes called the "cookie"). The disk has a large hole in the center, sometimes reinforced with a plastic or metal ring. The disk is sandwiched between two layers of non-woven, anti-static fabric called the //liner//. These are enclosed in a square plastic cover (usually PVC) with several holes cut out called the //jacket//.+8" and 5¼" floppies consist of a plastic disk coated with a magnetic medium (sometimes called the //cookie//). The disk has a large hole in the center, sometimes reinforced with a plastic or metal ring. The disk is sandwiched between two layers of non-woven, anti-static fabric called the //liner//. These are enclosed in a square plastic cover (usually PVC) with several holes cut out called the //jacket//.
  
-The plastic disk and the magnetic medium are the heart of the floppy disk as they hold the data. The magnetic coating on the plastic disk is very thin. For example, it is 2.794 μm (micrometers) thick for a high-density 8" floppy—about the length of an e. coli bacterium. It consists of magnetic powder (iron oxide) and a binder. Unfortunately, the formulation of the binder by different manufacturers in unknown. [[https://patents.google.com/patent/US5955169A/en|One patent]] lists the binder as "polyester polyurethane".((According to @bitsavers, whale oil was used as a tape lubricant until it was banned in the 1970s.))+The plastic disk and the magnetic medium are the heart of the floppy disk as they hold the data. The plastic disk is a thin sheet of mylar about 0.07 mm (70 μm) thick. The magnetic coating on the plastic disk is even thinner. For example, it is 2.794 μm (micrometers) thick for a high-density 8" floppy—about the length of an e. coli bacterium. It consists of magnetic powder (iron oxide) and a binder. Unfortunately, the formulation of the binder by different manufacturers in unknown. [[https://patents.google.com/patent/US5955169A/en|One patent]] lists the binder as "polyester polyurethane".((According to @bitsavers, any story you may have heard about whale oil being used as a tape lubricant is a [[https://gearspace.com/board/showpost.php?p=5926272&postcount=15&s=e0001c352c3200f021779fcae9c6e0b8|myth]] that originated in the 1990s.))
  
 The liner ensures that the plastic disk spins freely. It also collects dust and debris that find their way into the jacket. The liner can be made out of several kinds of fibers. It is imbued with an anti-static treatment which helps it attract and hold onto dust. It is usually physically bonded to the jacket. The liner ensures that the plastic disk spins freely. It also collects dust and debris that find their way into the jacket. The liner can be made out of several kinds of fibers. It is imbued with an anti-static treatment which helps it attract and hold onto dust. It is usually physically bonded to the jacket.
  
 The jacket protects the disk from rough handling and helps it maintain its shape. The jacket protects the disk from rough handling and helps it maintain its shape.
 +
 +=== 3½" ===
 +
 +3½" floppies are similar to 8" and 5¼" floppies in their major components, but differ in the details. 3½" floppies have a similar mylar disk coated with a magnetic medium, but the reinforcement ring is replaced with a stainless steel //hub//. The hub is attached to the disk with a ring of adhesive. The disk is still sandwiched between two sheets of fabric liner. The disk and liner are enclosed in a //shell// of plastic. Attached to the shell is a spring-loaded //shutter// that protects the media that is be exposed through the //head access slot// in the shell.
 +
 +The liner of 3½" floppies is similar to the liner of 8" and 5¼" floppies and serves the same purpose. One major difference is that it is not glued to the shell. It is held close to the disk with //wiper tabs// or //lifters//, which are small bent pieces of flexible plastic adhered to the shell. The wiper tabs keep the liner close to the disk to clean it as it spins.
 +
 +The shutter is made out of stainless steel. It is held closed by a spring. When a disk is inserted into a drive, the shutter is gently pushed out of the way to expose the magnetic medium to the drive heads.
 +
  
 ==== Problems ==== ==== Problems ====
Line 32: Line 46:
  
   * dust: disks left out of their sleeves can accumulate dust in the window   * dust: disks left out of their sleeves can accumulate dust in the window
-  * dirt and grime: in harsh environments, dirt and grime can accumulate on the disk surface+  * dirt and grime: in harsh environments, dirt and grime can accumulate on the disk surface during use
   * tar: if the disk has been used in a room with a smoker, tar can accumulate on the surface   * tar: if the disk has been used in a room with a smoker, tar can accumulate on the surface
   * mold: some molds can grow on the disk in certain temperatures and humidities   * mold: some molds can grow on the disk in certain temperatures and humidities
Line 40: Line 54:
 One of the biggest problems with disks that have a lot of build-up is that not only is the disk surface contaminated, but the liner is, too. In this case, merely spinning the disk in the drive can wear away the magnetic media, resulting permanent data loss. One of the biggest problems with disks that have a lot of build-up is that not only is the disk surface contaminated, but the liner is, too. In this case, merely spinning the disk in the drive can wear away the magnetic media, resulting permanent data loss.
  
-=== Weak binder ===+=== Weak binder (shedding) ===
  
 With time or the over-use of solvents, the binder can break down causing the magnetic oxide layer to flake away, resulting in permanent data loss. Trying to clean a disk with weak binder will probably destroy it. With time or the over-use of solvents, the binder can break down causing the magnetic oxide layer to flake away, resulting in permanent data loss. Trying to clean a disk with weak binder will probably destroy it.
Line 46: Line 60:
 === Loose ring === === Loose ring ===
  
-Over time, the glue holding the reinforcement ring to the disk may degrade, causing the ring to separate from the disk. This is usually recoverable //if// the ring doesn't rip the disk.+Over time, the glue holding the reinforcement ring to the disk may degrade, causing the ring to separate from the disk. This is usually recoverable for 5¼" disks //if// the ring doesn't rip the disk. For 3½" floppies, this is usually fatal as it is next to impossible to correctly center the hub. 
 + 
 +----
  
 ====== Considerations ====== ====== Considerations ======
Line 55: Line 71:
  
 If the answer is that keeping the disk physically intact is the most important thing, then you may not want to even try cleaning it. If the answer is that keeping the disk physically intact is the most important thing, then you may not want to even try cleaning it.
 +
 +----
  
 ====== Cleaning the disk surface ====== ====== Cleaning the disk surface ======
Line 72: Line 90:
 ==== Water ===== ==== Water =====
  
-Water is gentler on the magnetic media than other solvents.+Water is gentler on the magnetic media than other solvents. When disks are affected by mold, water is often sufficient to clean the media.
  
 TODO(flan): Example detergents and surfactants TODO(flan): Example detergents and surfactants
Line 81: Line 99:
  
 > When in doubt, look at the surface under magnification. If you do that with an alcohol based cleaner, you will never use it again. > When in doubt, look at the surface under magnification. If you do that with an alcohol based cleaner, you will never use it again.
 +
 +===== Success Stories =====
 +
 +==== 7jp4-guy ====
 +
 +[[https://discord.com/channels/901677188162658315/901677188607279136/1041160374419992656|7jp4-guy said]]:
 +
 +> OK. So I just did something that I am not sure if I should regret or not. I am working on a lot of LOAD'N'GO! disks for Apple II which are unpreserved and are badly damaged with mildew. I have tried cleaning the disks in the jacket using alcohol and repeatedly reading them. This has not been very successful to say the least. I ended up damaging the media in Frogger (one of the ones that is previously preserved so I did it first.) Next up was MAGIC MOVER which I don't think is preserved. After some thought, I decided to take a big risk and to damage it a bit in the hopes of saving the data. What I did was slit open the jacket, remove the media itself, wash it in water and then place it in a new jacket. The results were absolutely astonishing - both sides of the disk read on the first try without error.
 +
 +But this came at the cost of damaging the jacket, which is fine if you are really after the data. As david.rysk said:
 +
 +> Preserving the data is more important than the jacket, after all the physical artifact is kinda useless without the data.
 +
 +The flip side is that if the disk has been imaged, keeping the physical artifact intact might be preferable without trying to read the data (because that may destroy it).
  
 ====== Known Bad Brands ====== ====== Known Bad Brands ======
Line 88: Line 120:
 ^ brand  ^ products         ^ problem              ^ source ^ ^ brand  ^ products         ^ problem              ^ source ^
 | Wabash | floppies, tapes  | binder deterioration | [[https://forum.vcfed.org/index.php?threads/delicate-8%E2%80%9D-and-5%C2%BC%E2%80%9D-double-sided-floppy-disks-%E2%80%93-how-to-avoid-a-%E2%80%98bulldozer%E2%80%99-effect.1239735/post-1272149|Chuck on vcfed.org]] | | Wabash | floppies, tapes  | binder deterioration | [[https://forum.vcfed.org/index.php?threads/delicate-8%E2%80%9D-and-5%C2%BC%E2%80%9D-double-sided-floppy-disks-%E2%80%93-how-to-avoid-a-%E2%80%98bulldozer%E2%80%99-effect.1239735/post-1272149|Chuck on vcfed.org]] |
 +
 +
 +====== References ======
 +
 +  * Riaz, R. //Floppy disk//. How Products Are Made. Retrieved November 23, 2022, from http://www.madehow.com/Volume-1/Floppy-Disk.html 
 +  * PC Magazine. //Definition of floppy disk//. PCMAG. Retrieved November 23, 2022, from https://www.pcmag.com/encyclopedia/term/floppy-disk 
 +  * Masakazu Hoshino, Eizou Sakurai, Hajime Itoh, Kunio Iwase, Toshio Nagasaka (1999). //U.S. Patent No. 5,955,169//. Washington, DC: U.S. Patent and Trademark Office. Retrieved November 23, 2022, from https://patents.google.com/patent/US5955169A/en.