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Text File | 1993-10-24 | 30.3 KB | 609 lines

Rosenthal Engineering P.O.Box 1650, San Luis Obispo CA USA 93406 Copyright (C) 1993 All rights reserved. Disk Drive Cleaner When used with the special, NON-ABRASIVE, cleaning diskette and solvent available from Rosenthal Engineering, this program safely removes debris from the delicate read/write heads of floppy disk drives. Data loss, unreliable performance and errors can often be traced to microscopic foreign particles, dirt, dust, oxides and smoke that accumulates on the disk drive heads. - - - - - - - - - - - - How to Use Disk Drive Cleaner Copy the program and documentation to a working directory on your hard drive. If your floppy drive ever becomes so contaminated that it won't read a floppy diskette, you won't be able to read the Disk Drive Cleaner program from a floppy disk either, so save it on your hard drive now. To safely and effectively clean a floppy disk drive, dispense five drops of the cleaning solution, supplied with the kit, onto the fabric exposed by the head access slot of the special cleaning diskette. The cleaning solution is isopropyl alcohol, so use appropriate precations to avoid heat, flames and eye contact. Insert the cleaner diskette into the drive normally. Different areas of the cleaning disk are reserved for scrubbing, cleaning and polishing operations to avoid recontaminating the progressively cleaned heads. Only Rosenthal Engineering approved, NON-ABRASIVE cleaning disks may be used with this program. The fabric material of these diskettes is less abrasive than the industry specifications for the actual magnetic recording media. Run the Disk Drive Cleaner program from the DOS prompt. The program will prompt you to enter the letter of the drive to clean. The whole process takes less than four minutes to clean even the dirtiest drives. Take out the cleaning diskette. That's it, you're done! - - - - - - - - - - - - How to Obtain Approved cleaning kits. The file ORDER.FRM contains a convenient order form to register the software and order additional cleaning kits. Only NON-ABRASIVE cleaning kits, approved by Rosenthal Engineering may be used with this program. - - - - - - - - - - - - How to Try This Software Without a Cleaning Kit The best way to determine if any program will satisfy your needs is to try it for yourself. The Disk Drive Cleaner program may be run without any floppy diskettes in the drive for demonstration and evaluation. A message warning that you have not inserted an approved, NON-ABRASIVE cleaning disk will be displayed; however the program will function normally for your evaluation. To be effective, the special cleaning disk presents a running torque of at least 0.9 ozf-in (65 gcm) with the heads loaded, so without a disk in place, the demonstration will be considerably quieter than normal. Even without a cleaning diskette in place, you should have no difficulty hearing the drive go through its distinctly different cleaning cycles if you listen carefully. - - - - - - - - - - - - Other Methods of Disk Drive Cleaning There are two other methods used for cleaning floppy diskette drives. The first involves at least partial disassembly of the disk drive and direct cleaning of the heads and should be reserved for technically competent service personnel. The second follows the directions printed on nearly every cleaning disk kit available, but is not as effective as using the Disk Drive Cleaner program. Obsolete Cleaning Method I This method involves directly cleaning the internal disk drive heads and mechanism and should therefor, be left to competent technical personnel, regularly involved with manufacturers factory service. With the relatively low cost of new disk drives, it is rarely practical to invest in this level of service, unless the drive is special or particularly expensive to replace; For example, drives used in automatic mass disk duplicators. Standard drives may be easily replaced, and new drives are usually available for about the same (and often less) than the cost of repairing a worn drive. If a drive is particularly filled with debris, say from attempting to read a diskette buttered with peanut-butter and jelly, this may be the only method of salvation. The contaminated parts are gently cleaned with soft cotton rags and isopropyl alcohol. Several rags are used so the parts become progressively cleaned with fresh clean rags. Care is made to not recontaminate a freshly cleaned surface with a dirty cleaning implement. Cleaning the heads themselves must be done extremely delicately. Inside the outer plastic (Poly Chloride) jacket of a floppy diskette, is substrate material (polyethylene terephthalate), thinly (.0001 inch or 2 um nominal) coated with iron oxide (rust) and a binder. The heads themselves are designed to make intimate compact and ride directly on the magnetic medium. A delicate spring forces the read/write heads to ride against this very thin magnetic surface. Technicians must use extreme care to not exceed the the pressure normally exerted by the spring when burnishing the heads. To be effective burnishing heads must be done in-line with the read/write head gap. A read/write head is a very small core wound with a coil of fine wire. You can picture these tiny heads as a donut or bead (toroid) with a fine slot cut through it from the center to the outside. The toroid is then embedded in a ceramic or plastic material so the slot, or head gap as it's called, is exposed at a polished surface to contact the magnetic medium. The head gap rides perpendicular to the direction to travel of the disk lined up like the spokes of a wheel, and should be cleaned in that direction. When burnishing, the heads and cleaning fabric must be passed back and forth across the head gad following a radial path like the spokes and the diskette being the wheel. Technicians cleaning the heads directly can use isopropyl alcohol and "Lintless Head Cleaning Swabs" (General Cement #GC 32-3081 or Radio Shack #44-1094). Again, use several swabs so the head is not recontaminated, as the surface area of the swabs is far less than that of a cleaning diskette. This burnishing should be followed up with a normal cleaning using the Disk Drive Cleaning program, as your human technician (I hope this applies), can not physically burnish the heads at the same high speeds the program does so effectively. Technicians will also notice that the program will exercise the drive and heads with or without the cleaning disk in place. This can often be useful when freeing a drive mechanism or lubricating (*SPARINGLY PLEASE!*) sliding and bearing parts. Obsolete Cleaning Method II This is the "smear it around" method described on the package of every cleaning disk kit I've seen. You apply their cleaning solution to their paper or fabric cleaning diskette. The user then enters a DOS command like DIR and the computer tries unsuccessfully to read the single outside track until it gives up with an error. Abrasion is not generally of concern, because the heads are not oscillated or burnished across the cleaning disk and the disk only runs for about thirty seconds or less. In this "smear it around" method, only a very small area of the cleaning disk is used, and no effort is made to reserve different portions of the cleaning diskette for progressively cleaner operations. The relatively small area of the cleaning diskette that is accessed, quickly becomes contaminated, and the absolute maximum usage that can be squeezed out of a cleaning disk is between ten and fifteen times. Dirt from the heads is shared with the cleaning disk, and visa versa, until all are about equal. With no effort made to burnish the heads against the cleaning surface in a lateral gyrating radial motion (like cleaning spokes on a wheel) the most critical head gap area is not serviced as effectively as the Disk Drive Cleaner program does. The remaining residue is left to attract more debris so most of these "smear it around" method kits recommend repeat cleaning after only forty hours of use, or less. If a disk drive becomes so contaminated that it won't read the Disk Drive Cleaner reliably, you will get a DOS error message or an "Error! Program is corrupt." message. The only advantage to the smear it around method is to hopefully get the disk drive clean enough to at least load the Disk Drive Cleaner program. It's best to keep a copy of the Disk Drive Cleaner on your hard drive so you won't be depending on the same drive that has become unreliable to load the program. Other Drive Cleaning Considerations Modern computers employ cooling fans to circulate air through them for efficient operation. Unfortunately, along with the air comes dust and other particles. Sometimes the dust will accumulate sufficiently to cause mechanical problems with floppy disk drives. For example, there is a small hole near the center of the diskette which the computer uses to index and determine the position of the rotating disk. An electric eye, made up of a photo cell and a (often invisible infared) light emitting diode watches the hole. Other electric eyes monitor other holes and notches for write protection, media type, disk in position, etc. If dust accumulates to the point that any of these electric eye sensors becomes obscured, they won't function properly. This is rarely a problem, and can be corrected by simply vacuuming the disk drive through the slot. There are small, cute vacuum cleaners sold for this, but just use a standard tank and hose type vacuum cleaner with a small crevice tool attached. There is no need to invade the disk drive itself. If more cleaning is required, it should be done by a competent service technician. This type of cleaning is rarely required, but its description is included to be complete. - - - - - - - - - - - - Failures Caused by Dirty Disk Drive Heads The floppy disk drive read/write heads actually contact the magnetic oxide coating of the floppy diskette itself. This magnetic coating is very thin, in fact the thinner, the better, about 0.0001 inches or less. To understand how thin this is, a human hair is 0.003" (30 times larger), a dust particle is .0015" (15 times larger), a finger print is 0.006" (six times larger) and a tobacco smoke particle 0.00025 (2 1/2 times larger). The smallest separation of the head from the oxide coating will cause errors transferring data between the head and the diskette. Additionally diskettes are finished to a surface roughness of 3 microinch (76 um)AA maximum.... That means shiny smooth. The diskette rubs directly against the head at about 300-360 RPM, so this is no place for dirt and grit abrasive to the surface. With clean heads, a good quality diskette will typically have life expectancy for media wear of 5 million passes minimum. Clean, well maintained disk drives are more reiable and prevent accelerated wear and diskette deterioration. - - - - - - - - - - - - How Diskette Quality Affects Disk Heads As the coating of magnetic oxide passes across the head gap, a writing current passed through its windings forms an electromagnet that causes a magnetic flux to take the most conductive path across the gap in the head. Providing this gap is clean (especialy of magnetic oxides), the most magnetically conductive path is the surface of the oxide coating, which becomes magnetized and remains so even after the disk is removed. The data is stored as high as 17,436 bits (1's and 0's) per inch on a surface less than one sixth the thickness of a finger print. Reading the information back off the diskette is even more critical. As the magnetic medium passes across the head gap, the very tiny magnetized particles induce a voltage in the read/write head which recovers the data. As the dirt builds up between the magnetic medium and the critical head gap, the effective clipping rate detteriorates. The industry standard (ANSI) sets the minimum magnetic clipping level for diskettes at 40%. Typically a better quality diskette will be rated at least 60% and some even as good as 70%. A good judge of the quality of a diskette is the guaranteed minimum clipping level, but you'll have to ask the manufacturer. A dropout (which is a loss of data) is defined as signal level with an insufficient amplitude to be read consistently by the system. For example, a signal written at 6.0 volts and read back at 2.4 volts represents a 60% loss in signal amplitude, which means a signal of 40% remaining (a 40% clipping level). When dirt accumulates at the head gap, the recovered signal deteriorates rapidly and when a clipping rate falls below the industry standard, it is considered a missing bit (drop out) error. Another error that increases as the disk read/write heads become contaminated affects the peak voltage variance, or modulation error. Modulation is the difference (or variation) from the average signal. For example, if an average signal level produced when a diskette passes the head gap is 6.0 volts, but within a five millisecond time span rises to 6.6 volts, a modulation error of 10% has been measured. This error causes inaccurate write/read responses and becomes especially pronounced when the diskette is of low quality, damaged, irregular or the heads were not clean when the disk was recorded. With the close tolerances required to write and recover information between the heads and the diskette, the importance of using quality diskettes and periodically cleaning disk drives is obvious. - - - - - - - - - - - - How to Handle and Store Diskettes 1) No smoking. Tobacco smoke is one of the worst substances for causing damage to diskettes. Smoke particles are about two to three times the thickness of the diskettes magnetic oxide coating and are particularly nasty because of their sticky tar nature. Airborne smoke particles are drawn into the computer and circulated by the cooling fan. Smoke particles are about 1/7th the size dust particles, so air filters that trap the majority of dust may not restrict the smoke. Diskettes exposed to the air in the area around the computer are extremely vulnerable to smoke particles. Air, especially around high voltage sources like CRT monitors, gets charged with static electricity. The electrostaticly charged smoke particles then adhere to surfaces around the computer and the smoker. Floppy diskettes have a particular affinity to tobacco smoke, especially if they are exposed by being left out of their protective envelopes and storage boxes. 2) Keep a Clean Work Environment. Wash your hands and don't eat or drink when handling diskettes. When inserted into a disk drive, the contamination on the diskette will be scraped onto the read/write heads. The heads should be cleaned periodically using the Disk Drive Cleaner program and cleaning kits so the contamination accumulated on the heads does not migrate to other diskettes. If you exchange diskettes with others who may not take such precautions seriously, you should take it upon yourself to clean your own systems drives following the exchange. Never touch or attempt to clean the surface of the diskettes magnetic medium. 3) Keep Diskettes Away From Magnetic Fields. Contact with permanent magnets (like cute refrigerator magnets), transformers (like calculator type power supplies), electric motors and telephone bells create strong magnetic fields and will destroy your data. Keep magnetic fields away from diskettes and never allow magnets to be around your computer work area. 4) Don't Physically Abuse a Diskette. Don't bend, fold, paper clip, rubber band or place heavy objects on diskettes. Use only felt tip pens to gently write on diskette labels, never ball point pens and pencils. Keep diskettes out of direct sunlight and heat. Any of these will cause damage and loss of data. - - - - - - - - - - - - Protecting Your Valuable Data The best time to deal with a computer related problem is before you have one. Backup Copies The best way to protect your valuable data is to make copies of it, and keep it in a safe place, preferably at a different location. Safety backup disks made on computers properly maintained with the Disk Drive Cleaner, are more reliable should they ever be required. Periodic Maintenance Regularly scheduled periodic cleaning of your computers floppy disk drives will reduce data loss, unreliable performance and errors caused by microscopic foreign particles, dirt, dust, oxides and smoke that accumulates on the disk drive heads. How often you need to use the Disk Drive Cleaner depends on your computer's environment, the amount of use your floppy disk drive receive and the quality and cleanliness of the diskettes you use. For automatically fed disk drives employed in mass disk duplication on a continuous full time basis, it's not uncommon to use the Disk Drive Cleaner daily. These drives are usually specially modified for this type of service and are often quite expensive. If distribution disks are to be of consistently good quality, the drives must be properly maintained and clean. Well cleaned drives will produce better results and last longer with less repairs and down time. For computers in most non-smoking offices, most diskette manufactures recommend cleaning diskette drives after only 40 hours of use, and less if for environments of dust, smoke and dirt. Once every six months seems to satisfy the requirements of the majority of computer users. Cleaning disks used in non-smoking, low dirt and dust offices seem to be effective for at least ten to fifteen uses with this program. Use the ORDER.FRM file for ordering additional cleaning kits. Always order a few extra kits in the sizes you use, so you won't run out when you need them the most. - - - - - - - - - - - - Program Requirements Disk Drive Cleaner runs using DOS 3.0 or higher and has been tested with versions through 6.0. This program supports the approved cleaning kits available for all 3 1/2" and 5 1/4" double sided floppy disk drives configured as drives A-C. Sorry but 8" and single sided approved cleaning kits are not available except by special request. Use only NON-ABRASIVE cleaning disks approved by Rosenthal Engineering for use with this program. - - - - - - - - - - - - Software License agreement You are encouraged to copy and distribute this software provided it remains unmodified, complete in its original form, and no fee (other than a nominal copy charge) is required. This software is provided "as is" without warranty either expressed or implied. You may not make any changes or modifications to the software, and you may not decompile, disassemble or in anyway reverse engineer the software. This Software is copyrighted material. It is not sold, but licensed for use with cleaning kits and diskettes approved by Rosenthal Engineering. Only cleaning kits and diskettes approved by Rosenthal Engineering may be used with this software. This software is provided "as is" without warranties of any kind. Responsibility rests entirely with the user to determine its fitness for a particular purpose. ROSENTHAL ENGINEERING SHALL NOT IN ANY CASE BE LIABLE FOR SPECIAL, INCIDENTAL, CONSEQUENTIAL, INDIRECT OR OTHER SIMILAR DAMAGES ARISING FROM ANY USE OF THIS SOFTWARE. Some states may not allow these limits on warranties, so they may not apply to you. In no case shall Rosenthal Engineering's liability exceed the license fees paid by you to Rosenthal Engineering for the right to use the Licensed Software. This constitutes the entire agreement and understanding between the parties and supersedes any prior agreement or understanding whether oral or written and may only be modified in writing. Corporate, business, institutional and government users require an additional negotiated site license. - - - - - - - - - - - - Cleaning Solution The disk drive cleaning kit comes complete with isopropyl alcohol in a small bottle that makes it convenient to dispense for cleaning. If you require additional solvent, isopropyl alcohol is the same ingredient found in common rubbing alcohol and is available quite inexpensively from any pharmacy. Warning! Isopropyl alcohol is flammable. Keep away from heat and flames. Keep the cap tightly secured when not in use and out of the reach of children. Isopropyl alcohol is irritating to eyes, so avoid eye contact. If eye contact occurs, immediately flush eyes with plenty of water for at least ten minutes and call a physician. ================================================================ Material Safety Data Sheet June 16, 1993 Rosenthal Engineering P.O.Box 1650 San Luis Obispo, CA USA 93406 Trade name: Disk Drive Head Cleaning Kit ( Fluid ) ---------------------------------------------------------------- 1) Ingredient Isopropyl Alcohol C.A.S. Number .............. 67-63-0 Percent..................... 100% ---------------------------------------------------------------- 2) Physical Data Boiling point............... ca. 180.0 F Vapor Pressure.............. ca 33.0 mmHg Vapor Density............... ca. 5.0 Air=1 Evaporation rate............ ca. 0.80 Water=1 Solubility in water......... ca. 100.0 g/100 cc Specific gravity............ ca 0.800 Water=1 Percent volatile............ 100 Volatile organic compounds.. 785.00 gms/liter VOC less H2O & exempt solvents N/D ph.......................... 4.7 Viscosity................... N/D Melting point............... N/D Appearance.................. Clear liquid Odor........................ Alcohol odor ---------------------------------------------------------------- 3) Fire and Explosion Hazard Data Flash Point................. ca. 53.0 F Flammable limits - LEL...... ca. 2.0% Flammable limits - UEL...... ca. 12.0% Autoignition temperature.... N/D Extinguishing media......... CO2, Foam, Dry Chemical, Water Fog Special fire fighting procedures...... None Unsual fire and explosion hazards..... None NFPA Hazard codes Health........................... 2 Fire............................. 3 Reactivity....................... 0 Unusual reaction hazard.......... None ---------------------------------------------------------------- 4) Reactivity Data Stability............................. Stable Incompatibility: Materials/Conditions to avoid.... Heat Hazardous Polymerization: Hazardous polymerization will not occur. Hazardous decomposition products: Carbon Monoxide and Carbon Dioxide. ---------------------------------------------------------------- 5) Environmental information Spill Response: Refer to other sections of this MSDS for information regarding physical and health hazards, respiratory protection, ventilation and personal protective equipment. Extinguish all ignition sources. Cover and collect spilled fluid with absorbent material such as a paper wiping towel and clean up residue. Place in an approved metal container. Recommended Disposal: Incinerate in an industrial or commercial facility. Environmental data: Material to be disposed has a U.S. EPA hazardous number D001 (ignitable). SARA Hazard Class......... Yes Pressure.................. No Reactivity................ No Acute..................... Yes Chronic................... Yes ---------------------------------------------------------------- 6) Suggested First Aid Eye Contact: Immediately flush eyes with large amounts of water. Get immediate medical attention. Skin Contact: Flush skin with large amounts of water. If irritation persists, get medical attention. Inhalation: If signs/symptoms occur, remove person to fresh air. If signs/symptoms continue, call physician. If Swallowed: If swallowed, call a physician immediately. Only induce vomiting at the instruction of a physician. Never give anything by mouth to an unconscious person. ---------------------------------------------------------------- 7) Precautionary information. Eye protection................ Avoid eye contact. Skin protection............... Avoid skin contact. Recommended ventilation.. Use in a well ventilated area. Respiratory protection... Avoid inhalation of vapors. Prevention of Accidental Ingestion... Do not ingest. Recommended storage... Keep out of the reach of children. Fire and Explosion Avoidance: Keep away from heat, sparks, open flame, and other sources of ignition. Exposure Limits Ingredient Value Unit Type Auth Skin* --------------------- ----- ---- ---- ---- ----- Isopropyl Alcohol.... 400 PPM TWA ACGIH Isopropyl Alcohol.... 985 MG/M3 TWA ACGIH Isopropyl Alcohol.... 500 PPM STEL ACGIH Isopropyl Alcohol.... 1230 MG/M3 STEL ACGIH Isopropyl Alcohol.... 400 PPM TWA OSHA Isopropyl Alcohol.... 980 MG/M3 TWA OSHA Isopropyl Alcohol.... 500 PPM STEL OSHA Isopropyl Alcohol.... 1225 MG/M3 STEL OSHA * Skin Notation: Listed substances indicate with "Y" under SKIN refer to the potential contribution to the overall exposure by the cutaneous route including mucous membrane and eye, either by airborne or, more particularly, by direct contact with the substance. Vehicles can alter skin absorption. Source of Exposure Limit Data: ACGIH: American Conference of Governmental Industrial Hygienists. OSHA: Occupation Safety and Health Administration. ---------------------------------------------------------------- 8) Health Hazard Data Eye Contact: Moderate Eye Irritation: signs/symptoms include redness, swelling, pain, tearing, and hazy vision. Skin Contact: Mild Skin Irritation (after prolonged or repeated contact): signs/symptoms can include redness, swelling, and itching. PERSONS WITH PRE-EXISTING SKIN DISORDERS MAY BE MORE SUSCEPTIBLE TO DERMATITIS. Inhalation: Central Nervous System Depression: signs/symptoms can include headache, dizziness, drowsiness, incoordination, slowed reaction time, slurred speech, giddiness and unconsciousness. Irritation (upper respiratory): signs/symptoms can include soreness of the nose and throat, coughing and sneezing. If Swallowed: Ingestion may cause: Irritation of Gastrointestinal Tissues: signs/symptoms can include pain, vomiting, abdominal tenderness, nausea, blood in vomitus, and blood in feces. Central Nervious System Depression: signs/symptoms can include headache, dizziness, drowsiness, muscular weakness, incoordination, slowed reaction time, fatigue, blurred vision, slurred speech, giddiness, tremors and convulsions. Aspiration Pneumonitus: signs/symptoms can include coughing, difficulty breathing, wheezing, coughing up and pneumonia, which can be fatal. Other Health Hazard Information: DUE TO THE SIZE OF THE CONTAINERS AND THE POTENTIAL LOW LEVEL OF EXPOSURE TO THIS PRODUCT, MANY OF THESE HEALTH EFFECTS ARE NOT EXPECTED TO OCCUR UNDER ANTICIPATED USE CONDITIONS. -------------------------------------------------------------- Abbreviations: N/D - Not Determined N/A - Not Applicable -------------------------------------------------------------- The information on this Data Sheet represents our current data and best opinion as to the proper use and handling of this product under normal conditions. Any use of the product which is not in conformance with this Data Sheet or which involves using the product in combination with any other product or any other process is the responsibility of the user. ===============================================================