jcc@siemens.UUCP (03/12/85)
<> We are trying to decide between two companies for a disk cleaning and inspection contract. One company offers "shock watches" ( a warning device which tells you that a disk pack has been mishandled in such a way that its use can possible damage the heads of a drive ). Our environment is such that only a few people (about 5 or 6) handle disk packs. The company that offers the "shock watches" quoted us a price about 50% more than the competition. I would like to hear from other people who were in the situation. Are the "shock watches" worth the extra money considering the fact that the disks are in a "stable" environment? All comments and suggestions are appreciated. Joe Camaratta princeton!siemens!jcc
peterb@pbear.UUCP (03/14/85)
That ought to be backwards. Its more work to inspect all disks to see if any are out of round, warped than it is to know which ones are known to be mishandled. If other than the shock watches the services match, I'd recommend saving the money. This also hinges on how good your staff is at handling the packs. Peter Barada ima!Pbear!peterb
59231ig@houxm.UUCP (I.GERSZBERG) (03/21/85)
<> We have those "shock watchers" on our disk packs. We have never seen one of those things set yet!!! One time we had a head crash, we took the (fortunately single) pack which had been destroyed and dropped it onto the floor from 2-3 feet....and the shock indicator STILL HAD NOT GONE OFF!!!!! EXPLAIN THAT ONE! Then we dropped it again from a greater height and the thing finally showed (just a little though). I'll let you draw your own conclusions from this experiment. Bob Switzer
herbie@watdcsu.UUCP (Herb Chong [DCS]) (03/22/85)
In article <1181@houxm.UUCP> 59231ig@houxm.UUCP (I.GERSZBERG) writes: ><> >We have those "shock watchers" on our disk packs. We have never seen >one of those things set yet!!! One time we had a head crash, we took the >(fortunately single) pack which had been destroyed and dropped it >onto the floor from 2-3 feet....and the shock indicator STILL HAD NOT >GONE OFF!!!!! EXPLAIN THAT ONE! Then we dropped it again from a greater height >and the thing finally showed (just a little though). I'll >let you draw your own conclusions from this experiment. > >Bob Switzer i worked at a place once that askd me to do a little research into these gadgets for testing how likely something was to be damaged when shipped in a certain way. most of these gadgets are little steel balls held in place by springs or other variations on this. almost all of them are rated for 30G's or more before they trip. small ones as low as 15G's are hard to find and expensive. we found that, after some calculations using idealized numbers to mazimize acceleration, that a typical object dropped from about 1m undergoes about 8 to 10 G's of acceleration. in other words, these things would trip only if the forces are large enough to physically damage the exterior of the objects (in corrugated cardboard boxes). they aren't useful for other types. Herb Chong... I'm user-friendly -- I don't byte, I nybble.... UUCP: {decvax|utzoo|ihnp4|allegra|clyde}!watmath!water!watdcsu!herbie CSNET: herbie%watdcsu@waterloo.csnet ARPA: herbie%watdcsu%waterloo.csnet@csnet-relay.arpa NETNORTH, BITNET, EARN: herbie@watdcs, herbie@watdcsu