4 Jun
2023
4 Jun
'23
11:15 p.m.
Last time I worked with large pack drives was the three RM03's in 2003
or so before I sent AI to LCM. One of the drives had dirty heads and I
cleaned them with isopropyl. Mounted a scratch pack and it exploded.
Other two drives were clean and worked fine before powering down,
parking, and putting away.
CDC drives have glue or something that is not compatible with alcohol.
RL01/02/RK05/RK03's do not seem to have this issue, I have
cleaned/replaced those heads without issue.
One important thing: Check the air filter before doing anything. On one
of my RL02's the heads were sanded down like cheese wedges and it took
me a bit to realize the filter was plugged and not enough air was going
over them to allow them to fly properly. Then again that system was used
at Solarex, where they cut wafers for solar panels. Filter was choked
with silicon dust. Oi..
CZ
On 6/4/2023 7:07 PM, Robert Ollerton via cctalk wrote:
cp-v at the LCM, system and swapping on 300MB packs.
On Sun, Jun 4, 2023 at 3:16 PM P Gebhardt via cctalk <cctalk(a)classiccmp.org>
wrote:
> Hi Rod,
>
> I don't blame them either! Operating these drives means having access to
> spare heads, alignment equipment and and alignment pack - not taking into
> account the work to be put in all of this!
> Anyway, thanks for sharing your anecdote with us :)
> Greetings,
> Pierre
>
>
>> I can't say I blame them. It was a lot of work to get a drive running
> after a head crash. If it was a bad crash, there >could be extensive
> cleaning to be done followed by replacing one or more heads. Then the new
> heads had to be >aligned. If you hadn't cleaned thoroughly enough, you
> risked damaging the expensive alignment disk.
>> Once I came back from lunch to see the operators had 3 drives open. They
> kept swapping a disk pack which was >giving I/O errors to new drives and
> were crashing heads along the way due to the damaged disk pack. I stopped
>> them before they spun up the pack on a 4th drive. That wasn't as bad as
> the time one of them dropped a disk pack >and bent platters. That ripped
> heads completely out of the mounting mechanism.
>> Ah, the good old days!
>>
>> Rod
>> On Jun 2, 2023, at 2:51 AM, P Gebhardt via cctalk <cctalk(a)classiccmp.org>
> wrote:
>> Hi all,
>>
>> I just came across pictures on the LCM website about their SDS Sigma
> installation there.
>> On the pictures, one can see 10-platter disk packs in the corner and
> stored on the disk drives.
>> Did the LCM ever had these in operation, either for data retrieval or
> even demo purposes?
>> I know of the Jim Austin Computer museum where they fixed a CDC 9766
> drive but it suffered
>> a head crash after a few hours according to their description which led
> to giving up the operation
>> of these drives.
>>
>> Greetings,
>> Pierre
>>
>>
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