RL02 Pack tear-down and clean (was: Lorlin Impact Test System Disk...)

On Sunday 06 March 2011, Tony Duell wrote: I have two RL02's on my 11/34C and one on my 11/83. I have a spare RL02 which I recently rebuilt (including new heads), and a working spare RL01. Given that I use RL02 packs regularly - especially on my 11/34C, I felt it critical that I carefully clean and verify packs as much as possible before mounting them in a RL0x drive. Let me say upfront that I've successfully used this procedure on the 32+ packs that I have in stock - which are all 100% - no bad blocks (some using substitute records, of course). I have six or seven packs in storage that did not pass initial "inspection", which I have never mounted in an RL02 for testing. I have not had one crash using a pack that passed this procedure. Tear-down / Clean Procedure --------------------------- Supplies/Tools needed: 1. Dust/Lint free wipes (such as KimWipes S-200) 2. Single ended swabs - 6" rigid white birch shaft 3. Absolute Isopropyl Alcohol (I use Zero Residue, 99.953% Pure Anhydrous) 4. Appropriate non-magnetic tip screwdriver(s) 5. High powered LED flashlight 6. Super clean well washed hands, dried with a lint free towel (or wipes). 7, Lint free clothing Environment: Room which is close to a dust free "Clean Room" as possible. I have a lab in my home which contains only electronic gear. It is far removed from any dust producing areas such as bedrooms, washer/dryers, etc. "Pet free" is also critical. Keep the door of such a room closed while doing this procedure. (No fans!) Procedure: 1. Most Digital packs have a Digital supplied "impact" detector. If it shows red - it's a warning that the pack has been mishandled by a drop or some other impact and may be damaged. It does NOT mean that the pack IS damaged. On the other hand, if the detector shows a clear/white indication, it does NOT mean the pack is O.K. to mount! 2. Clean the outside of the pack with wipes and alcohol. Remove all loose labels, adhesive, etc. 3. Hold the release and lift the handle as if you were going to place the pack in a drive. The protective bottom of the pack will be released. Put the bottom in a safe place (NOT the floor) while you work on the pack. 4. Place the handle in its normal locked position, and prepare to remove the plastic shield covering the bottom of the pack. Older packs will have small Philips head screws which should be completely removed. Newer packs will have "slots" which look like they are made for screwdrivers. There are eight such slots on a pack. Use a small flat head screwdriver to pry (outward direction) each slot until the plastic shield lifts. When the last slot is "released", or the last screw removed, the bottom will slip off. You will now be able to see the platter (bottom) completely. 5. Look carefully at the platter. Are there any scratches or "dings" on it? If so, you can stop here - and consider the platter not worth cleaning or testing. The platter's surface should be even and shiny (don't worry about dust - we'll deal with that later). 6. Now release the handle as if you were going to mount the pack. This will allow you to move the platter at an angle so you can see the top surface of the platter. Examine it for scratches or "dings" as you did for the other side. In the same manner, if you see scratches or dings, forget about using the pack. 7. Now hold the pack so that you can observe if it is "out-of-true". In other words, make sure that the platter is not warped in any way. This check is especially important if the impact sensor displayed "red". 8. Assuming that the platter looks good, we can now begin to clean it. Take a wipe and wrap it around the hard wood handle of the swab (it will take multiple turns of the swab to roll up the entire wipe). The rolled up wipe will just about cover the entire length of the swab. Holding the wipe so it doesn't unroll, put it into the alcohol. Remove the wipe and place it on the platter at an angle similar to a "spoke" on a bike. Holding the swab/wipe in place, spin the platter gently so that the entire surface of the platter becomes covered with the alcohol from the wipe. One pass (revolution) is usually all that is necessary. 9. Now look at the wipe. It should be clean - NO BROWN spots. If you see brown on the wipe, it means that there was probably a crash that you somehow missed on your visual inspection. 10. Assuming that the lint was clean (except for dust), we can now move on to the other surface. Remove the wipe, and place it in a safe place (we will use it later). Put a new wipe on the swab, dip it in the alcohol and do the same now for the other side of the platter. This is a bit trickier - but once you get the knack of it, it's easy. 11. Again look at the wipe. There should be NO BROWN spots. Assuming all is well, remove the wipe from the swab, and place it aside to be used later. We will now begin another visual inspection. 12. Shine a bright LED flashlight on the surface of the platter. If you hold it at the correct angle, you will be able to see any small particles which remain on either surface of the platter. If you've done the above correctly, there should be very few. Use a clean wipe (with no alcohol) to gently pick up any remaining particles. A little practice makes this easy. 13. Now place the handle of the pack in the locked position, and put the pack in a safe place. Put some alcohol on one on the wipes you used to clean the platter and use the wipe to clean the both sides of the plastic shield. Retrieve the pack and place the plastic shield on the pack. When you've lined it up correctly, all the screw holes or slots should line up perfectly (it only goes on one way!). If the pack had screws, replace them all. If it had "slots", gently snap the bottom back into place. 14. Do a final visual inspection of the platter using the LED flashlight. Don't worry if you see a speck or two of particulate on the shiny surface of the platter. The RL0x drive will blow off any remaining loose particles that happened to drift back on your platter while you were putting it back together. 15. Use the remaining wipe you used to clean the platter by pouring alcohol on it and using it to clean the pack bottom which you removed in step #3. Once you've cleaned it, put it back on the pack. 16. Now you are ready to test the pack. I usually use RT-11, and the DIR/BAD command. This will scan every block on the pack and tell you if any are bad. I typically then check to see if the pack is setup for RT, RSX, RSTS or UNIX and look at it's contents before using it. That's a totally different subject ;-) I may well do that - although I didn't get any "bites" for the Lorlin files. (And yes, everything else is standard RT-11 except for a few thousand test results in binary - of which I have no information as to what was being tested or the format/structure of the data). Cheers, Lyle -- Lyle Bickley, AF6WS Bickley Consulting West Inc. http://bickleywest.com "Black holes are where God is dividing by zero"