Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Pete Lancashire via cctalk]

>>Ah, oh How should that get between the heads and the platter?

If it can happen it will. It did. I had saved up three or four cartridges
for future repair. I was told such work should be done by
(someone not so expensive) so off they went to one of the manufacturing
repair techs. I was busy a few weeks later and did
not do my usual look inside. Spun up the RK05 and data errors all over the
place. Pulled the cart, did a head inspection and
there was a not the usual black/dark brown streak on the head. Go get the
box of Texwipes, etc and pull out the RK, but the
head just did not feel smooth, if you have done such a cleaning a dozen
times you get to know the feeling when you know
things are flat again.  So time to take the cartridge apart. Its screws
needed very little torque, as in a couple pretty much
fell out. Yep the inside was full of plastic shards. Later found out the
tech used an air screwdriver to put the screws back.

Anyway, I put a DO NOT USE sticker on the door and called DEC, yep .. the
head had to be replaced. For years I kept
it on my desk as a reminder that maybe the department who keep the
compressors, pumps, wirewrap machines etc
running was not a way to save money.

Exact details somewhat fuzzy since this was like 1976

-pete

On Mon, Apr 3, 2017 at 6:33 AM, Philipp Hachtmann via cctalk <
cctalk@classiccmp.org> wrote:

>
>
> Another thing to watch out for is the two halves of some if not all
>> were screwed together with self tapping screws. When you take
>> them apart bit of plastic may come out of the holes or fall off the
>> insides of the screw threads. That plastic if gets between the platter
>> and head will not be to the heads advantage.
>>
> Ah, oh How should that get between the heads and the platter? It's
> nearly impossible to get something of substantial size into that gap.
> Look at the RK05 manual (and pack bag): It's the *really* small stuff that
> gets into the wrong place.
> Normal dust from the paper you used for cleaning (and from your working
> environment) is kicked off the platter by the head. Makes funny sounds.
>
> My procedure: Clean the disk, load it, manually visit the whole surface
> with the heads. If it crashes or clinging does not go away soon, reclean.
> If the disk has become silent and is running nicely, I give the heads a
> "quick brutal cleaning": Towel with IPA, between the heads, load heads onto
> the towel, move towel until heads clean. Must be done carefully...
>
> I once had an RC05 disk crashing. With an awful noise and a white stripe
> on the disk. After cleaning, both heads and disks were fully functional
> again. But I have also seen packs which look perfect but either keep making
> heavy sound or having data errors.
>
> Philipp
>
>

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Philipp Hachtmann via cctalk]

On 01/05/2017 02:22 PM, Noel Chiappa wrote:

> From: Klemens Krause

> We clean our RK05 disks in a very robust way: with cheap burning spirit
> and paper towels. ... We rubbed away thick black traces from occasional
> head crashes and we never removed the oxide coating with this torture.

I am about to get a large batch of RK05 packs, so I am interested in the
details of this.

First, what is 'burning spirit'? (I assume this is a straight translation
into English of some German term, but not knowing German... :-) After poking
around with Google for a while (hampered no little by the fact that it's the
name of a band, and also a term in World of Warcraft :-), it seems like it
might be acetone?


In Germany, "burning spirit" is 96% ethanol + something that tastes 
awfully + some water. No other kinds of alcohol involved as far as I 
know. Some people are able to remove the awful taste in the lab.


I usually use 100% IPA to wash my RK05 packs...
I don't let acetone get near my stuff. It probably will remove the 
laquer. Nice prep if you want to apply a new coating to your disk.


I do it like Klemens: Scrub, scrub, scrub. The black spots MUST be 
removed. Important not to lay the disk onto a hard or somehow grain 
contaminated surface while scrubbing.



BTW: The RK05 manual explicitly warns from WATER on the disks. You 
should not spit (i.e. blow!) onto the surfaces as water is said to 
dissolve the coating.


Philipp

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Philipp Hachtmann via cctalk]

Another thing to watch out for is the two halves of some if not all
were screwed together with self tapping screws. When you take
them apart bit of plastic may come out of the holes or fall off the
insides of the screw threads. That plastic if gets between the platter
and head will not be to the heads advantage.
Ah, oh How should that get between the heads and the platter? It's 
nearly impossible to get something of substantial size into that gap.
Look at the RK05 manual (and pack bag): It's the *really* small stuff 
that gets into the wrong place.
Normal dust from the paper you used for cleaning (and from your working 
environment) is kicked off the platter by the head. Makes funny sounds.


My procedure: Clean the disk, load it, manually visit the whole surface 
with the heads. If it crashes or clinging does not go away soon, 
reclean. If the disk has become silent and is running nicely, I give the 
heads a "quick brutal cleaning": Towel with IPA, between the heads, load 
heads onto the towel, move towel until heads clean. Must be done 
carefully...


I once had an RC05 disk crashing. With an awful noise and a white stripe 
on the disk. After cleaning, both heads and disks were fully functional 
again. But I have also seen packs which look perfect but either keep 
making heavy sound or having data errors.


Philipp

Re: Cleaning RK05 packs

[Fritz Mueller via cctalk]

The first two packs I opened up for cleaning had foam around the inside of the 
hub.  If it is decaying like the rest of the foam DEC used this seems like it 
could be a problem inside the packs?

I haven’t seen this discussed before in any of the RK05 pack cleaning threads.  
Do folks usually leave this be, or remove it?

cheers,
   —FritzM.

Re: Cleaning RK05 packs

[Marc Howard via cctalk]

BTW, have you replaced the emergency head retract batteries and/or allowed
them to reach full charge?

Marc

On Sat, Apr 1, 2017 at 2:01 PM, Fritz Mueller via cctalk <
cctalk@classiccmp.org> wrote:

>
> > On Jan 5, 2017, at 8:48 AM, Rick Bensene  wrote:
> >
> > The method I've used very successfully for unknown packs is:
> >
> > 1) I first mount the pack in a drive that has a good absolute filter,
> > and has had the head load disabled, and spin it for a few hours.
>
> I’m getting to the point in my RK05 restore where I’m about ready to try
> spinning up a pack so I can work through the various offline dynamic
> checks.  I have a pretty clean looking pack to start with (has been stored
> in plastic bag, etc) that doesn’t have any particularly valuable data (just
> an RKDP backup, according to the label, and I have the original as well).
> But I thought it’d be prudent to give it a clean first anyway just in case.
>
> In step one of the process quoted above, is it enough to put the toggle on
> the servo amp board in the down position to disable head load?  Or is it
> best to disable head load in some other way (e.g. jumpers on the backplane,
> or disconnecting any particular cables?)
>
> thanks!
>—FritzM.
>
>

Re: Cleaning RK05 packs

[Fritz Mueller via cctalk]

> On Apr 1, 2017, at 2:53 PM, Marc Howard  wrote:
> 
> BTW, have you replaced the emergency head retract batteries and/or allowed 
> them to reach full charge?

Yes, have done replacement.  Haven’t put a charge on them yet, but figured 
running the drive for a couple hours with disabled head load I could de-dust my 
first candidate pack while simultaneously charging the batteries.

cheers,
   —FritzM.

Re: Cleaning RK05 packs

[Fritz Mueller via cctalk]

> On Jan 5, 2017, at 8:48 AM, Rick Bensene  wrote:
> 
> The method I've used very successfully for unknown packs is:
> 
> 1) I first mount the pack in a drive that has a good absolute filter,
> and has had the head load disabled, and spin it for a few hours.

I’m getting to the point in my RK05 restore where I’m about ready to try 
spinning up a pack so I can work through the various offline dynamic checks.  I 
have a pretty clean looking pack to start with (has been stored in plastic bag, 
etc) that doesn’t have any particularly valuable data (just an RKDP backup, 
according to the label, and I have the original as well).  But I thought it’d 
be prudent to give it a clean first anyway just in case.

In step one of the process quoted above, is it enough to put the toggle on the 
servo amp board in the down position to disable head load?  Or is it best to 
disable head load in some other way (e.g. jumpers on the backplane, or 
disconnecting any particular cables?)

thanks!
   —FritzM.

Re: Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[Pete Turnbull]

On 07/01/2017 18:01, Pete Turnbull wrote:

That part is easy.  Turn it upside down, and for each of the tabs,
insert a small (1/4") flat-blade screwdriver into the rectangular hole
by each tab, turn it so that the side moves away from the bottom cover
sufficiently, then slip a smaller screwdriver into the gap between the
side and the bottom cover, and lever it up slightly.  Repeat until you
have all the tabs undone and the bottom cover lifts off.

That lets you at the lower surface.  I can't remember how to take the
platter out; IIRC it involves dong something to the cover on the handle.
I just use a torch to look at it, through the side.


A little refresher (experimentation) later...

Take the cover (the part with the slide) off the handle.  Inside you'll 
see a white bar with two inset steel pins that hold the hooks that hold 
the platter hub.  The handle pivots on plastic parts at each side; take 
them out.  That lets you slide the whole handle, when it's in the down 
position, about 1/4" towards the edge.  Do that, making sure the white 
plastic bar moves with the handle, and it will release the pins from the 
hooks and the platter will fall out (so do this with it resting on a 
safe surface - NOT in the lid, or the hub's magnets will stick it to the 
lid).


--
Pete
Pete Turnbull

Re: Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[Pete Turnbull]

On 07/01/2017 16:44, Jerry Weiss wrote:


What is the best way to approach evaluating old RL02 Packs for
cleaning?  Does anyone have experience opening up all the little
plastic tabs on the covers? I have a large stash of RL02’s that I had
planned to backup.   I was planning on just doing a visual inspection
on each before loading.


That part is easy.  Turn it upside down, and for each of the tabs, 
insert a small (1/4") flat-blade screwdriver into the rectangular hole 
by each tab, turn it so that the side moves away from the bottom cover 
sufficiently, then slip a smaller screwdriver into the gap between the 
side and the bottom cover, and lever it up slightly.  Repeat until you 
have all the tabs undone and the bottom cover lifts off.


That lets you at the lower surface.  I can't remember how to take the 
platter out; IIRC it involves dong something to the cover on the handle. 
I just use a torch to look at it, through the side.


I wouldn't worry about a little fine dust.  It's not an RK05 and they're 
very robust.  I once had one make a wierd noise when spun up - the 
"ting" did sound a little like an RK05 head crash.  It turned out a 
spider had decided it was a good warm dry place to live, but all I had 
to do was clean the rest of the spider off the head.


--
Pete
Pete Turnbull

Re: Drum Computers (Was Cleaning things (was Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)))

[Chuck Guzis]

On 01/07/2017 07:01 AM, Al Kossow wrote:
> On 1/7/17 3:06 AM, jim stephens wrote:
> 
>> They did make a tape drive of some sort
> 
> They made several generations, what I've found on their cartridge
> tape drives is under 3M on bitsavers. All use variations of their
> trade secret or what eventually became QIC standard tape formats.
> 
> The 1/4" tape drive division was sold to Gorgens Industries in San
> Diego

You can find non-3M tape drives with 3M-copyrighted ROMs inside.  I have
one such--an ADIC Iotamat drive, which uses, IIRC, a 6800 CPU.

As far as QIC, goes, it was cheap and it aged badly.  I recall calling
3M (long before the Imation spinoff) asking about a DC300 tape cart that
I had where the driver misfunctioned and the tape came off the reel.

I was advised by the tech support guy to disassemble the cartridge and
moisten the loose end of the tape with saliva and stick it to the takeup
reel and manually wind the tape until I reached the BOT marker holes,
then reassemble the cartridge.  It worked, but he seemed to be a bit
ashamed to tell me to use saliva as a temporary adhesive.

FWIW, I'd always found the techs at 3M/Imation or the Federal operation
set up by them to be very helpful.

None of which makes me like QIC any better.

--Chuck

Re: Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[j...@cimmeri.com]

On 1/7/2017 11:44 AM, Jerry Weiss wrote:
What is the best way to approach evaluating old RL02 Packs for 
cleaning? Does anyone have experience opening up all the little 
plastic tabs on the covers? I have a large stash of RL02’s that I had 
planned to backup. I was planning on just doing a visual inspection on 
each before loading. The only disassembly information I have found 
uses the proverbial hammer - 
http://williambader.com/museum/vax/43rl02topremoval.jpg 
 Jerry 


With mine, in a darkened room, I shone a flashlight in perpendicularly 
to reveal what debris was on the platter surface.  In all cases of the 
few packs I had to process, there was a light coating of dust on the 
platters, so I disassembled the pack and washed as previously posted.


For me, they had to be dust free before use.

They were not hard to diassemble, but there was a trick to the handle 
part (which I forget).


- J.

Re: Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[Jerry Weiss]

> On Jan 7, 2017, at 3:42 AM, Pete Turnbull  wrote:
> 
> On 07/01/2017 04:08, Robert Armstrong w#rote:
>>> Paul Koning  wrote:
>>> one would think unplugging the power to the head actuator coils  ...
>> 
>>  One might think that, and that plan works for an RK05, but an RL02 is
>> smarter.  Unless the heads go on cylinder within a few seconds of the head
>> load signal, the drive logic just faults and spins down again.  Not very
>> useful...  What's needed is a way to stall or fake out the drive startup
>> state machine logic.
> 
> I haven't done this for a while, but I think it might work if you also 
> disable the SK TO (Seek Timeout) signal on the main logic board, and maybe 
> also POS SIG (Position Signal).
> 
> There are several setup and adjustment procedures that require one to move 
> the heads by hand, including right back onto the loading ramp. You'd do this 
> with the cover open, the logic board swung up and resting on its clip at the 
> back of the drive, and with the amplifier box turned to a vertical position 
> sitting on its right-hand supports.  The procedures require the above signals 
> to be disabled, and the servo drive (the single inline connector under the 
> amplifier box) to be disconnected.  However, they all start by pressing LOAD 
> and allowing the heads to load at least as far as the loading area at the 
> outside edge of the disk before disconnecting the servo drive; I can't 
> remember if the heads actually go beyond that into the area where the data 
> tracks are.
> 
> How you disable the signals depends on the version of the main logic board - 
> there are three different types, all described in the pocket service guide.
> 
> -- 
> Pete
> Pete Turnbull


What is the best way to approach evaluating old RL02 Packs for cleaning?  Does 
anyone have experience opening up all the little plastic tabs on the covers?  
I have a large stash of RL02’s that I had planned to backup.   I was planning 
on just doing a visual inspection on each before loading.

The only disassembly information I have found uses the proverbial hammer  - 
http://williambader.com/museum/vax/43rl02topremoval.jpg 


Jerry

Re: Drum Computers (Was Cleaning things (was Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)))

[Al Kossow]

On 1/7/17 3:06 AM, jim stephens wrote:


They did make a tape drive of some sort


They made several generations, what I've found on their cartridge tape 
drives is under 3M on bitsavers. All use variations of their trade 
secret or what eventually became QIC standard tape formats.


The 1/4" tape drive division was sold to Gorgens Industries in San Diego

further discussion at 
http://www.vcfed.org/forum/archive/index.php/t-52604.html

Re: Drum Computers (Was Cleaning things (was Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)))

[Chris Elmquist]

On January 7, 2017 5:06:32 AM CST, jim stephens  wrote:
>
>
>On 1/6/2017 6:46 PM, Rick Bensene wrote:
>> Today, there seems to be no record that 3M ever was in the computer
>business.  But...it was.
>They inflicted the write only media on the world that became QIC. So 
>they were in the biz long enough to do that.
>
>Media never intended to be recorded at the densities most devices 
>recorded at, and never intended to have the tape move at the speeds it 
>did inside the cartridge.  Won't go on and on about it, old topic.
>
>They did make a tape drive of some sort, I recall seeing they marketed 
>something to read and write their own tapes a very long time ago.
>
>thanks
>jim

Everything "computer" that 3M did became Imation's and the Imation world 
headquarters here in Oakdale MN is now a giant empty building with a tattered 
"for lease" tarp covering up the Imation logo sign at the entrance to the 
property.  Rumor has it the facility may become the HQ for a furniture store 
called Slumberland.  Oh, the irony.

Chris

-- 
Chris Elmquist

Re: Drum Computers (Was Cleaning things (was Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)))

[jim stephens]

On 1/6/2017 6:46 PM, Rick Bensene wrote:

Today, there seems to be no record that 3M ever was in the computer business.  
But...it was.
They inflicted the write only media on the world that became QIC. So 
they were in the biz long enough to do that.


Media never intended to be recorded at the densities most devices 
recorded at, and never intended to have the tape move at the speeds it 
did inside the cartridge.  Won't go on and on about it, old topic.


They did make a tape drive of some sort, I recall seeing they marketed 
something to read and write their own tapes a very long time ago.


thanks
jim

Re: Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[Pete Turnbull]

On 07/01/2017 04:08, Robert Armstrong w#rote:

Paul Koning  wrote:
one would think unplugging the power to the head actuator coils  ...


  One might think that, and that plan works for an RK05, but an RL02 is
smarter.  Unless the heads go on cylinder within a few seconds of the head
load signal, the drive logic just faults and spins down again.  Not very
useful...  What's needed is a way to stall or fake out the drive startup
state machine logic.


I haven't done this for a while, but I think it might work if you also 
disable the SK TO (Seek Timeout) signal on the main logic board, and 
maybe also POS SIG (Position Signal).


There are several setup and adjustment procedures that require one to 
move the heads by hand, including right back onto the loading ramp. 
You'd do this with the cover open, the logic board swung up and resting 
on its clip at the back of the drive, and with the amplifier box turned 
to a vertical position sitting on its right-hand supports.  The 
procedures require the above signals to be disabled, and the servo drive 
(the single inline connector under the amplifier box) to be 
disconnected.  However, they all start by pressing LOAD and allowing the 
heads to load at least as far as the loading area at the outside edge of 
the disk before disconnecting the servo drive; I can't remember if the 
heads actually go beyond that into the area where the data tracks are.


How you disable the signals depends on the version of the main logic 
board - there are three different types, all described in the pocket 
service guide.


--
Pete
Pete Turnbull

RE: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[CuriousMarc]

Here is the exact reference for the clean room wipes:

Berkshire DURX 670
Item #: DR670.0404.10
4"x4" (10cm x10 cm)
Non-woven Polyester/Cellulose

And isopropyl alcohol we use is 99.9%, not just 99 as I said.

Marc

-Original Message-

We use 6"x6" clean room rated wipes (I think they were either Berkshires or
Kimwipes) from Grainger and 99% isopropyl alcohol from Fry's. Won't scratch,
free of microscopic dust and lint, and 99% alcohol will leave no drying
marks (it's typically the last rinse in IC manufacturing). May cost you a
bit. Wipe your work area before and use clean room gloves.
Marc

> On Jan 5, 2017, at 6:40 AM, Al Kossow  wrote:
> 
> isopropyl alcohol works. TFE is better, if you have some stashed.
> 
> If you can find them anywhere, Texwipe made a plastic wand that looks 
> like a tongue depressor with a slit down the middle and a lint free 
> sleeve called the Texsleeve (tx300 sleeve, tx800 wand) that you would 
> use to clean heads
> 
> Minor head crashes leave a tar-like residue that you need to remove. A 
> pack inspector is a handy thing to have (spinle with microscope and 
> illuminator on the rack and pinion) to look for surface damage.

 

RE: Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[Robert Armstrong]

>Paul Koning  wrote:
>one would think unplugging the power to the head actuator coils  ...

  One might think that, and that plan works for an RK05, but an RL02 is
smarter.  Unless the heads go on cylinder within a few seconds of the head
load signal, the drive logic just faults and spins down again.  Not very
useful...  What's needed is a way to stall or fake out the drive startup
state machine logic.

Bob

RE: Drum Computers (Was Cleaning things (was Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)))

[Rick Bensene]

Allison wrote;

>I envy the chance to restore a LGP-30 or for that fact play with one. 
>Many of the things I remember
>mid sixties on are now gone or were rare then.  Like small desk sized drum 
>computers using transistors or first generation IC (RTL and RDTL).


I so regret not having rescued an old computer that I played with through all 
four years of high school.  

The machine was made by Minnesota Mining and Manufacturing (aka 3M 
Corporation). Today, there seems to be no record that 3M ever was in the 
computer business.  But...it was.   The system was designed expressly for 
process control.  Kind of makes sense for 3M to develop a system like this, 
since most of the manufacturing they did needed process controls, and at the 
time, computers were  getting to into that role in place of electromechanical 
systems.

The system was given to our high school by the local Natural Gas public utility 
that used the system from the mid-1960's through the early-1970's for 
monitoring and controlling gas flow in pipelines.  It was replaced by more 
modern computer, a PDP-11 of some variety, IIRC.

This 3M machine was a dual processor system, with two identical CPUs that could 
communicate to each other through a common register located in an I/O rack. The 
original process control software was designed so that both CPUs would operate 
in tandem, each doing a different part of the job.  One CPU mainly did all of 
the I/O interfacing and data normalization, and the other CPU did the number 
crunching and processing for the process control, feeding results back to the 
I/O CPU to control the physical stuff, and generating reports on an IBM 
typebar-type output typewriter.  Operator interaction with the process control 
system was through a Teletype 33-ASR terminal.

The CPUs were transistorized.  I recall that the cards were arranged in a U 
fashion looking at the CPU chassis from the top, some power supply circuitry 
and relays at the top of the U, the circuit cards making up the sides and 
bottom of the U, and the drum memory module in the middle..  Each CPU was 
something like 12RU height, and were in a small desk-high standard 19" 
equipment rack, with the CPUs stacked one above the other.

The CPUs were 24-bit word machines, with an 8K-word magnetic drum as main 
memory.Instructions had five bits for the opcode, and two address fields, 
one for operand location (drum address in block/track/sector format) or in the 
case of some instructions a short constant number), and also a next instruction 
address (again in block/track/sector format).
 
The I/O rack had the interprocessor communication register, along with 
registers for reading the time from a transistorized  Parabam real-time clock 
(HH:MM:SS) in 24-hour time (The clock had those wonderful projection-type 
incandescent displays to show the current time), a Teletype current-loop 
interface at 110 baud, an interface for communication the IBM wide-carriage 
output typewriter (which we never we able to get working), and a whole slew of 
relay outputs, contact closure inputs, digital to analog converters with line 
drivers, and comparators with counters connected that could act as 
software-driven analog to digital converters, event counters, etc.  One last 
output interface was a register that was write-only that could enable or 
disable an old Mallory Sonalert that would generate an ear-splitting shriek 
when turned on.  There were also two banks of decimal thumbwheel switches, one 
with three digits, and another with 8 digits, that could be read from the CPU 
4-bits at a time through an I/O register.

 When I got to high school in 1974, the drum in one of the CPUs had suffered a 
bearing failure and crashed hard.   The instructor of the computing curriculum 
looked into seeing if the drum could be repaired, but it would have been 
prohibitively expensive, so the drum was removed from this CPU and used as a 
prop for illustrating different types of memory technology to his students.

The other CPU ran fine through my years of high school, and I learned a great 
deal about programming at the machine level from the old 3M (I for the life of 
me can't remember the model number of the machine).

I fondly remember  writing an "alarm clock" program where a time in HHMMSS form 
could be wheeled into the low six digits of the eight-digit thumbwheel 
register, and when the time there matched the time on the Parabam clock, it'd 
fire off the Sonalert, and print an arbitrary message on the teletype 
repeatedly until the program was halted by dialing a stop code read from the 
three digit thumbwheel switch bank when the program was started. Once the 
program was started, I'd scramble the three digit thumbwheels, so no one but me 
would know the code to stop the program.  You might think that  you could just 
press the "STOP" button on the console...but there was a Plexiglas cover with a 
small padlock lock on it that covered the console controls...and I 

Re: Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[Tony Duell]

On Fri, Jan 6, 2017 at 6:27 PM, Robert Armstrong  wrote:

>   Speaking of spinning up a pack without loading the heads, can anyone tell
> me how to do this on an RL01/2 drive?

I am pretty sure you unplug the positioner motor from the DC power supply
PCB. You have to remove the latter (4 corner screws and a plastic cover
that identifies the testpoints) and it's a 2 pin plug on the underside
(component side) of the board.

-tony

Re: Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[Paul Koning]

> On Jan 6, 2017, at 1:27 PM, Robert Armstrong  wrote:
> 
>> Rick Bensene  wrote:
> 
>> 1) I first mount the pack in a drive that has a good absolute filter, and
> has
>> had the head load disabled, and spin it for a few hours.  
> 
>  Speaking of spinning up a pack without loading the heads, can anyone tell
> me how to do this on an RL01/2 drive?

I don't know a specific answer, but one would think unplugging the power to the 
head actuator coils would do the job.

paul

Spinning up RL02 w/o head load ? (was Cleaning RK05 packs)

[Robert Armstrong]

> Rick Bensene  wrote:

>1) I first mount the pack in a drive that has a good absolute filter, and
has
> had the head load disabled, and spin it for a few hours.  

  Speaking of spinning up a pack without loading the heads, can anyone tell
me how to do this on an RL01/2 drive?

Thanks,
Bob Armstrong

Re: Cleaning things (was Cleaning RK05 packs (Was: LGP-30 Memory Drum Update))

[allison]

On 01/06/2017 07:32 AM, David Bridgham wrote:
> On 01/05/2017 08:13 PM, allison wrote:
>
>> Lots of ifs, mights, and maybes.   My knowledge is from actually owning
>> and maintaining a Cessna since 1979 and so far that has not been an issue.
> Yup, that's just how the discussion in the aircraft community went.  One
> group would point out that Simple Green contained chemicals known to
> corrode aluminum while another group would say they'd been using the
> stuff on their airplanes and hadn't noticed any problems.  Then the
> company came out with Simple Green Extreme, promoting it as being safe
> for aircraft though never actually saying, as far as I saw, that the
> regular Simple Green wasn't safe.
>
>
I see that as the maker responded to a perceived problem and did their
marketing!

The bottom line is its seriously off topic and likely not an issue.  
To get on topic over the years I've used a number of things deemed bad
with full success.

An example was a few Altair era board with green crud plus dirt from the
prior holder storing them.
The green crud was the gold over copper plated contacts without nickel
over copper.  I decided
to keep them and ran them through the dishwasher with the usual
dishwasher caustic cleaner
(cascade) and the oven dry them.  They came out looking better than
factory and it even cleaned
the contacts.  They tested fine and I stripped the damaged gold and
re-plated the contacts with
electroless tin (didn't have the materials for nickel then gold) and
sill have them.  Back then the
locals on the board told me the boards would be ruined.

When doing repairs or restoration the person/organization doing it needs
to fist have goals, then
process, and the skills to implement them and maybe even mitigate side
effects.  What process
they use and can apply is dependent on available materials and the
available skills. Our advantage
now is is world wide near instant communication to ask what is best,
easy, fast, or cheap.

I envy the chance to restore a LGP-30 or for that fact play with one. 
Many of the things I remember
mid sixties on are now gone or were rare then.  Like small desk sized
drum computers using transistors
or first generation IC (RTL and RDTL).


Allison

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Pete Lancashire]

>>The latter 91% is safe for many uses and is water clear it leaves no residue
>>(however one must assure its dry after).

And what type of microscope did you use to determine there is no residue ?

On Thu, Jan 5, 2017 at 9:23 AM, allison  wrote:
> On 1/5/17 8:36 AM, E. Groenenberg wrote:
>>
>> We have a similar common name for it being 'brand spiritus'.
>>
>> It's basically 90% - 92% alcohol, with the rest being methanol and water
>> and it's color is blue-ish.
>>
>> Ed
>> --
>
>
> In the past from the local print and painting supplier "De-natured alcohol"
> Usually in a pint or gallon can (this is USA).  I also buy Lacquer thinner,
> Acetone, Ethanol (99.4pure) and MEK in the same form all powerful
> solvents and better than 99% pure.
>
> Rubbing alcohol is ok save for its isopropanol plus water (either 70% or
> 91%).
> The latter 91% is safe for many uses and is water clear it leaves no residue
> (however one must assure its dry after).
>
> There is also Rubbing Alcohol that is ethanol plus water with an added
> denaturant
> (toxic) to render it safe for skin use and not for drinking.
>
> GC chemicals supplies two different residue free solvent cleaners.
>
> My favorite head cleaner was banned in many places Xylene, takes curd
> off like no tomorrow.  May melt the user too.
>
> As to cleaning and repairing the drum... DO NOT TOUCH ANYTHING UNTIL
> YOU ARE SURE of the process to be applied.  That applies to solvents, wipes,
> and all.  Use gloves!  Test solvents near an edge or other area that is not
> critical.
>
>
> Allison
>
>
>> Ik email, dus ik besta.
>> BTC : 1J5fajt8ptyZ2V1YURj3YJZhe5j3fJVSHN
>> LTC : LP2WuEmYPbpWUBqMFGJfdm7pdHEW7fKvDz
>>
>> On Thu, January 5, 2017 14:22, Noel Chiappa wrote:
>>>
>>>  > From: Klemens Krause
>>>
>>>  > We clean our RK05 disks in a very robust way: with cheap burning
>>> spirit
>>>  > and paper towels. ... We rubbed away thick black traces from
>>> occasional
>>>  > head crashes and we never removed the oxide coating with this
>>> torture.
>>>
>>> I am about to get a large batch of RK05 packs, so I am interested in the
>>> details of this.
>>>
>>> First, what is 'burning spirit'? (I assume this is a straight translation
>>> into English of some German term, but not knowing German... :-) After
>>> poking
>>> around with Google for a while (hampered no little by the fact that it's
>>> the
>>> name of a band, and also a term in World of Warcraft :-), it seems like
>>> it
>>> might be acetone?
>>>
>>> Noel
>>>
>>
>
>

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[David Bridgham]

On 01/05/2017 08:13 PM, allison wrote:

> Lots of ifs, mights, and maybes.   My knowledge is from actually owning
> and maintaining a Cessna since 1979 and so far that has not been an issue.

Yup, that's just how the discussion in the aircraft community went.  One
group would point out that Simple Green contained chemicals known to
corrode aluminum while another group would say they'd been using the
stuff on their airplanes and hadn't noticed any problems.  Then the
company came out with Simple Green Extreme, promoting it as being safe
for aircraft though never actually saying, as far as I saw, that the
regular Simple Green wasn't safe.

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[curiousmarc3]

We use 6"x6" clean room rated wipes (I think they were either Berkshires or 
Kimwipes) from Grainger and 99% isopropyl alcohol from Fry's. Won't scratch, 
free of microscopic dust and lint, and 99% alcohol will leave no drying marks 
(it's typically the last rinse in IC manufacturing). May cost you a bit. Wipe 
your work area before and use clean room gloves.
Marc

Sent from my iPad

> On Jan 5, 2017, at 6:40 AM, Al Kossow  wrote:
> 
> isopropyl alcohol works. TFE is better, if you have some stashed.
> 
> If you can find them anywhere, Texwipe made a plastic wand that looks like
> a tongue depressor with a slit down the middle and a lint free sleeve
> called the Texsleeve (tx300 sleeve, tx800 wand) that you would use to clean 
> heads
> 
> Minor head crashes leave a tar-like residue that you need to remove. A pack 
> inspector
> is a handy thing to have (spinle with microscope and illuminator on the rack 
> and pinion)
> to look for surface damage.
> 
> On 1/5/17 5:22 AM, Noel Chiappa wrote:
>>> From: Klemens Krause
>> 
>>> We clean our RK05 disks in a very robust way: with cheap burning spirit
>>> and paper towels. ... We rubbed away thick black traces from occasional
>>> head crashes and we never removed the oxide coating with this torture.
>> 
>> I am about to get a large batch of RK05 packs, so I am interested in the
>> details of this.
>> 
>> First, what is 'burning spirit'? (I assume this is a straight translation
>> into English of some German term, but not knowing German... :-) After poking
>> around with Google for a while (hampered no little by the fact that it's the
>> name of a band, and also a term in World of Warcraft :-), it seems like it
>> might be acetone?
>> 
>>Noel
> 

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Chuck Guzis]

On 01/05/2017 05:13 PM, allison wrote:
>> Freon TF works well on everything.  Too bad it's not available.
>> 
>> Is it still used for aircraft electronics?
> No its been obsoleted.  There are many other similar but not
> fluorinated hydrocarbons that are preferred and also good old soap
> and water.

No, it's been banned.  "Obsoleted" to me carries the implication that
there's something better.  TF was banned under the Montreal Protocol not
for its toxicity, but for the ozone-depletion characteristic of the
stuff when it was released into the atmosphere.  Same goes for most
chlorinated refrigerants.

HCFC-225 had been an adequate substitute, but that was phased out in
2015.  Too bad--it was almost as good as a cleaner.

Techspray (and NASA and a bunch of other outfits) have proposed some
possible alternatives;

https://www.techspray.com/t-ak225ban.aspx

If these were my packs, I'd drop them a line and see what they recommend
for the specific application.

FWIW, I buy my denatured ethanol from the paint store--it's about as
water-free as it's possible to get, usually with some methanol commonly
added as a denaturing agent, although other substances can be used.
This was a practice started in 1906 so that manufacturers could be
exempted from alcohol taxation.

During Prohibition, the government, responding to a higher moral
standard, reformulated the denaturing agents, making them even more
lethal.  The result was dramatic--in 1928, 700 people died in New York
alone from consumption of industrial alcohol.  Oddly, the 18th amendment
only forbade manufacture, sale and transportation of alcohol.
Consumption was still perfectly legal.

Paint-store alcohol is free of water because it's commonly used as a
shellac solvent/carrier.  Any appreciable amount of water results in a
cloudy finish.

FWIW,
Chuck

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Jon Elson]

On 01/05/2017 11:38 AM, Pete Lancashire wrote:

you could test various solvents with a Q-tip to make sure they don't cause 
damage.

And a week later after the binder had decomposed what are you going to do ?


That's why you test in a non-critical area, and then let it 
sit for a while to make sure it doesn't cause slow 
deterioration.  And, of course, with a general idea of the 
material (plated nickel vs. oxide/epoxy) you can select 
solvents that are known to not attack that material.


Jon

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[allison]

On 01/05/2017 07:15 PM, Chuck Guzis wrote:
> On 01/05/2017 03:24 PM, David Bridgham wrote:
>
>> This question of whether Simple Green was aluminum safe came up in
>> the aircraft world a few years back and the answer turned out to be
>> that some ingredient in there is mildly corrosive to aluminum.  Not
>> badly so and if you managed to flush it off with water then no
>> problem but if a bit of cleaner were to weep into a crack and not get
>> get cleaned off then over time it might be a problem.  Not too long
>> after that Simple Green came out with a new formulation, Simple Green
>> Extreme or something like that, that *was* aluminum safe.  So look
>> for the Simple Green that's sold for cleaning airplanes if you're
>> cleaning around aluminum.
Lots of ifs, mights, and maybes.   My knowledge is from actually owning
and maintaining a Cessna since 1979 and so far that has not been an issue.
FYI often cleaning the bird is good no matter what you use as salt spray
and
other things it can be exposed to are far worse.  Like acid rain and soot
from fires.

>
> Freon TF works well on everything.  Too bad it's not available.
>
> Is it still used for aircraft electronics?

No its been obsoleted.  There are many other similar but not fluorinated
hydrocarbons that are preferred and also good old soap and water.


Allison

>
> --Chuck
>

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Marc Howard]

"A pack inspector is a handy thing to have (spinle with microscope and
illuminator on the rack and pinion)"

Can you post a picture of this critter?  Is it something we could 3D print?

Thanks,

Marc

On Thu, Jan 5, 2017 at 6:40 AM, Al Kossow  wrote:

> isopropyl alcohol works. TFE is better, if you have some stashed.
>
> If you can find them anywhere, Texwipe made a plastic wand that looks like
> a tongue depressor with a slit down the middle and a lint free sleeve
> called the Texsleeve (tx300 sleeve, tx800 wand) that you would use to
> clean heads
>
> Minor head crashes leave a tar-like residue that you need to remove. A
> pack inspector
> is a handy thing to have (spinle with microscope and illuminator on the
> rack and pinion)
> to look for surface damage.
>
> On 1/5/17 5:22 AM, Noel Chiappa wrote:
> > > From: Klemens Krause
> >
> > > We clean our RK05 disks in a very robust way: with cheap burning
> spirit
> > > and paper towels. ... We rubbed away thick black traces from
> occasional
> > > head crashes and we never removed the oxide coating with this
> torture.
> >
> > I am about to get a large batch of RK05 packs, so I am interested in the
> > details of this.
> >
> > First, what is 'burning spirit'? (I assume this is a straight translation
> > into English of some German term, but not knowing German... :-) After
> poking
> > around with Google for a while (hampered no little by the fact that it's
> the
> > name of a band, and also a term in World of Warcraft :-), it seems like
> it
> > might be acetone?
> >
> >   Noel
> >
>
>

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[allison]

On 1/5/17 12:30 PM, Al Kossow wrote:


On 1/5/17 9:22 AM, j...@cimmeri.com wrote:


As Allison taught me, the oxide surface on platters / drums is just a form of 
inactive RUST.. and therefore, unaffected
by water (no, the water doesn't cause it to start rusting further).

The interface between the aluminum platter and the steel sector ring 
would be a really bad thing to get water into.
Simple Green is a earth safe (Eco) detergent with a PH of 8.5 to 9.5.  
Safe for many things
as a mild great and organic residue remover.  Used that or Woolite for 
washing aluminum

aircraft for decades.

Water is not the hazard, allowing it to remain without drying is as it 
promotes corrosion.

Pure water (non-ionic) is mostly inactive.

FYI: Decades ago I used to do radio repair for the maritime set and a 
salt dunked radio
that was still dripping from its dunking in salt water was immediately 
without prejudice
immersed in clean water.  It was then again immersed in new fresh clean 
water.  The goal
was to remove the salt and then DRY (in a 160 degree Fahrenheit oven) 
the unit before
active corrosion could take over.  It was usually successful if the unit 
hadn't remained
submerged for more than a few hours  or allowed to sit around for more 
than a few
hours as if it it electrolytic corrosion from dissimilar metals would 
take over and kill it.
It was also effective on intermittent marine gear that had gotten flaky  
from salt tracking

on the board over time.

Allison

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[allison]

On 1/5/17 10:56 AM, Mouse wrote:

In the US, "rubbing alcohol" is mostly denatured ethanol (though "isopropyl$

Interesting.  I don't think I've ever seen a bottle of "rubbing
alcohol" that was anything but isopropanol-and-water.  But I'm more
Canadian than US.

Many are possible in the local apothecary (aka drug store in local lingo).

ISO70% + water
ISO91% + water
Ethanol (denatured)+ water

Then there are products with oil of wintergreen (green color) and other 
additives

and are identified on label.


I would suggest avoiding these blends of random chemicals made with no real $

Or, more precisely, with _different_ concern for purity.  For rubbing
alcohol you want to avoid biologically active contaminants, but
dissolved solids per se don't matter.  Here, you care about dissolved
solids but don't much care about things that might be biologically
active, as long as they evaporate without residue.
Generally there are no solids in the first three and are safe for 
cleaning gear

is the materials are not affected by the alcohol in use.


Which leads me to tentatively suggest gasoline (West Pondian) / petrol
(East Pondian), since it seems to me that will go to some lengths to
avoid fouling engines with residues.  And it's available pretty much
universally, and relatively cheaply.
NO!  Highly flammable and contains a laundry list of things.  Good 
enough for cleaning
an engine of oil (with great care).  Oddly Kerosene (aka paraffin) can 
be had as (K1 crystal)
highly refined.  Again it can acquire impurities from the source but can 
also be purchased

in small containers for camp stoves and lamps.


Or am I wrong about it not leaving even trace residues?
There is what was called "white gas" that was pure petrol extracts 
without additives.

These days if you see it its for camp stoves and lights and not cheap.


Of course, anyone with distillation equipment could distil any of these
to get something with less residue.  But not everyone has chem-lab
glassware.
Or the temperature controls to not render unsafe(highly flammable) 
lighter gasses



Allison

/~\ The ASCII Mouse
\ / Ribbon Campaign
  X  Against HTML   mo...@rodents-montreal.org
/ \ Email!   7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[allison]

On 1/5/17 8:36 AM, E. Groenenberg wrote:

We have a similar common name for it being 'brand spiritus'.

It's basically 90% - 92% alcohol, with the rest being methanol and water
and it's color is blue-ish.

Ed
--


In the past from the local print and painting supplier "De-natured alcohol"
Usually in a pint or gallon can (this is USA).  I also buy Lacquer thinner,
Acetone, Ethanol (99.4pure) and MEK in the same form all powerful
solvents and better than 99% pure.

Rubbing alcohol is ok save for its isopropanol plus water (either 70% or 
91%).
The latter 91% is safe for many uses and is water clear it leaves no 
residue

(however one must assure its dry after).

There is also Rubbing Alcohol that is ethanol plus water with an added 
denaturant

(toxic) to render it safe for skin use and not for drinking.

GC chemicals supplies two different residue free solvent cleaners.

My favorite head cleaner was banned in many places Xylene, takes curd
off like no tomorrow.  May melt the user too.

As to cleaning and repairing the drum... DO NOT TOUCH ANYTHING UNTIL
YOU ARE SURE of the process to be applied.  That applies to solvents, wipes,
and all.  Use gloves!  Test solvents near an edge or other area that is 
not critical.



Allison


Ik email, dus ik besta.
BTC : 1J5fajt8ptyZ2V1YURj3YJZhe5j3fJVSHN
LTC : LP2WuEmYPbpWUBqMFGJfdm7pdHEW7fKvDz

On Thu, January 5, 2017 14:22, Noel Chiappa wrote:

 > From: Klemens Krause

 > We clean our RK05 disks in a very robust way: with cheap burning
spirit
 > and paper towels. ... We rubbed away thick black traces from
occasional
 > head crashes and we never removed the oxide coating with this
torture.

I am about to get a large batch of RK05 packs, so I am interested in the
details of this.

First, what is 'burning spirit'? (I assume this is a straight translation
into English of some German term, but not knowing German... :-) After
poking
around with Google for a while (hampered no little by the fact that it's
the
name of a band, and also a term in World of Warcraft :-), it seems like it
might be acetone?

Noel

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Pete Lancashire]

>>you could test various solvents with a Q-tip to make sure they don't cause 
>>damage.

And a week later after the binder had decomposed what are you going to do ?

On Thu, Jan 5, 2017 at 9:05 AM, Jon Elson  wrote:
> On 01/05/2017 07:22 AM, Noel Chiappa wrote:
>>
>>  > From: Klemens Krause
>>
>>  > We clean our RK05 disks in a very robust way: with cheap burning
>> spirit
>>  > and paper towels. ... We rubbed away thick black traces from
>> occasional
>>  > head crashes and we never removed the oxide coating with this
>> torture.
>>
>> I am about to get a large batch of RK05 packs, so I am interested in the
>> details of this.
>>
>> First, what is 'burning spirit'? (I assume this is a straight translation
>> into English of some German term, but not knowing German... :-) After
>> poking
>> around with Google for a while (hampered no little by the fact that it's
>> the
>> name of a band, and also a term in World of Warcraft :-), it seems like it
>> might be acetone?
>>
> I'd be very careful with acetone, it tends to dissolve a lot of things, like
> maybe the binder in the coating.
> Rubbing alcohol (isopropyl) and pure ethanol are the things I've seen used
> to clean magnetic media.
> if there is a spot that is not actually used (maybe other parts of the
> gouged tracks) you could test various solvents with a Q-tip to make sure
> they don't cause damage.
>
> Jon
>

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Chuck Guzis]

On 01/05/2017 03:24 PM, David Bridgham wrote:

> This question of whether Simple Green was aluminum safe came up in
> the aircraft world a few years back and the answer turned out to be
> that some ingredient in there is mildly corrosive to aluminum.  Not
> badly so and if you managed to flush it off with water then no
> problem but if a bit of cleaner were to weep into a crack and not get
> get cleaned off then over time it might be a problem.  Not too long
> after that Simple Green came out with a new formulation, Simple Green
> Extreme or something like that, that *was* aluminum safe.  So look
> for the Simple Green that's sold for cleaning airplanes if you're
> cleaning around aluminum.


Freon TF works well on everything.  Too bad it's not available.

Is it still used for aircraft electronics?

--Chuck

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Lyle Bickley]

On Thu,  5 Jan 2017 08:22:05 -0500 (EST)
j...@mercury.lcs.mit.edu (Noel Chiappa) wrote:

> > From: Klemens Krause  
> 
> > We clean our RK05 disks in a very robust way: with cheap
> > burning spirit and paper towels. ... We rubbed away thick black
> > traces from occasional head crashes and we never removed the
> > oxide coating with this torture.  
> 
> I am about to get a large batch of RK05 packs, so I am interested in
> the details of this.
> 
> First, what is 'burning spirit'? (I assume this is a straight
> translation into English of some German term, but not knowing
> German... :-) After poking around with Google for a while (hampered
> no little by the fact that it's the name of a band, and also a term
> in World of Warcraft :-), it seems like it might be acetone?

I'm sure I've discussed cleaning packs on this list before, but here
goes again :)

I've cleaned a LOT of RL02 and RK05 packs. Both are relatively easy to
clean, but patience is definitely a virtue.

1) I clean the external surface of the pack with a damp cloth to
eliminate dirt and dust. Then I dry off any dampness with a clean, dry
cloth.

2) I open (unscrew or unclip depending on the model) the pack and
carefully set the screws (if any) in a clean (dust free) plastic box.

3) I examine the pack surface for crashes - and if there are visible
"hits" or "groves" in the pack, I discard it immediately.

4) Assuming the surface is good, I then use Lint Free Professional
Swabs saturated with Pure Anhydrous Isopropyl Alcohol (99.953% pure) to
clean the entire surface of the disk.

5) If there are any dirt buildup spots (NOT the result of a crash), I
use Lint Free Professional Chamois Swabs, saturated with the above
Alcohol, to gently clean up the spot. BTW, in my experience, this step
is rarely required.

6) After cleaning, I use a Lint Free Texwipe to GENTLY clean the entire
surface of any dust or other particulate.

6) I then clean all of the internal casing using Texwipe and the
above alcohol.

7) I re-assemble the disk and examine it for any dust particles with a
bright LED flashlight. If there are any visible dust particles, I use a
filtered air supply to blow away the dust.

NOTE: When replacing screws in packs, be super careful not to tighten
the screws too hard. Tightening too much can strip the plastic threads
and introduce plastic particulate on to the disk.

I've cleaned over 40 RL0x and RK05 packs using this method - and all
have subsequently worked perfectly.

NOTE: All of the above products are available online or at any
electronic supply house. The Pure Anhydrous Isopropyl Alcohol on the
container says: "For cleaning fiber optics, semi-conductors, contacts,
magnetic tape, medical equipment and other electronic devices. Zero
residue". Cost here in Silicon Valley is about $8 for 1 Litre.

Lyle
--
73AF6WS
Bickley Consulting West Inc.
http://bickleywest.com

"Black holes are where God is dividing by zero"

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[David Bridgham]

On 01/05/2017 12:22 PM, j...@cimmeri.com wrote:
>
> It's very mild and has been aluminum safe for me (think, aluminum
> wheels on cars).

This question of whether Simple Green was aluminum safe came up in the
aircraft world a few years back and the answer turned out to be that
some ingredient in there is mildly corrosive to aluminum.  Not badly so
and if you managed to flush it off with water then no problem but if a
bit of cleaner were to weep into a crack and not get get cleaned off
then over time it might be a problem.  Not too long after that Simple
Green came out with a new formulation, Simple Green Extreme or something
like that, that *was* aluminum safe.  So look for the Simple Green
that's sold for cleaning airplanes if you're cleaning around aluminum.

Dave

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Tony Duell]

On Thu, Jan 5, 2017 at 5:30 PM, Al Kossow  wrote:
>
>
> On 1/5/17 9:22 AM, j...@cimmeri.com wrote:
>
>> As Allison taught me, the oxide surface on platters / drums is just a form 
>> of inactive RUST.. and therefore, unaffected
>> by water (no, the water doesn't cause it to start rusting further).
>>
>
> The interface between the aluminum platter and the steel sector ring
> would be a really bad thing to get water into.
>

I seem to remember that at least some RK05 packs have a piece of foam inside the
hub (no idea what for, and it doesn't seem to be the Evil Foam that
turns to dust
or gunge). Get that soaked with water and you will have some interesting effects
when you spin up!

-tony

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Tony Duell]

> Another thing to watch out for is the two halves of some if not all
> were screwed together with self tapping screws. When you take
> them apart bit of plastic may come out of the holes or fall off the
> insides of the screw threads. That plastic if gets between the platter
> and head will not be to the heads advantage.

I seem to recall that one of the RK05 manuals warned that when re-fitting
said screws you should always put them in, turn them anticlockwise
until the threads engage and then tighten them clockwise. Just
screwing them in not only risks (as ever) stripping the thread in the
plastic housing, but also the action of cutting the new thread may
cause bits of plastic to break loose and they might (will!) end up
where they shouldn't

-tony

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[j...@cimmeri.com]

On 1/5/2017 12:30 PM, Al Kossow wrote:


On 1/5/17 9:22 AM, j...@cimmeri.com wrote:


As Allison taught me, the oxide surface on platters / drums is just a form of 
inactive RUST.. and therefore, unaffected
by water (no, the water doesn't cause it to start rusting further).


The interface between the aluminum platter and the steel sector ring
would be a really bad thing to get water into.


Yeah, if you let it sit there long 
enough, but wiped dry (and let to sit to 
dry further), it's not going anywhere.


- J.

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[j...@cimmeri.com]

It's very mild and has been aluminum 
safe for me (think, aluminum wheels on 
cars).


As Allison taught me, the oxide surface 
on platters / drums is just a form of 
inactive RUST.. and therefore, 
unaffected by water (no, the water 
doesn't cause it to start rusting further).


- J.

On 1/5/2017 12:21 PM, Al Kossow wrote:

http://simplegreen.com/downloads/SDS_EN-US_SimpleGreenAllPurposeCleaner.pdf

not something I would think of using on a disk surface

On 1/5/17 8:59 AM, Liam Proven wrote:

On 5 January 2017 at 17:11, j...@cimmeri.com  wrote:

- apply some Simple Green to a microfiber cloth


I may be the odd one out here, but what on Earth is "Simple Green?"

https://www.youtube.com/watch?v=TkZFuKHXa7w

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Al Kossow]

On 1/5/17 9:22 AM, j...@cimmeri.com wrote:

> As Allison taught me, the oxide surface on platters / drums is just a form of 
> inactive RUST.. and therefore, unaffected
> by water (no, the water doesn't cause it to start rusting further).
>

The interface between the aluminum platter and the steel sector ring
would be a really bad thing to get water into.

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Al Kossow]

http://simplegreen.com/downloads/SDS_EN-US_SimpleGreenAllPurposeCleaner.pdf

not something I would think of using on a disk surface

On 1/5/17 8:59 AM, Liam Proven wrote:
> On 5 January 2017 at 17:11, j...@cimmeri.com  wrote:
>> - apply some Simple Green to a microfiber cloth
> 
> 
> I may be the odd one out here, but what on Earth is "Simple Green?"
> 
> https://www.youtube.com/watch?v=TkZFuKHXa7w
> 

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[j...@cimmeri.com]

On 1/5/2017 11:59 AM, Liam Proven wrote:

On 5 January 2017 at 17:11, j...@cimmeri.com  wrote:

- apply some Simple Green to a microfiber cloth


I may be the odd one out here, but what on Earth is "Simple Green?"

https://www.youtube.com/watch?v=TkZFuKHXa7w



Ever heard of Soylent Green?  Same 
stuff, but with more water added. :)


- J.

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Pete Lancashire]

DEC (branded, made by Texwipe) cleaning pads contained 99% isopropyl
alcohol. The most important part was being non abrasive.
I would consider using Texwipe or other brands of non abrasive
materials before I even though about a solvent.

I remember a disk being being cleaned with common paper towels, when
that person was done you could see the scratches all over the platter.

At one time the system I ran had over 200 packs in use.

Another thing to watch out for is the two halves of some if not all
were screwed together with self tapping screws. When you take
them apart bit of plastic may come out of the holes or fall off the
insides of the screw threads. That plastic if gets between the platter
and head will not be to the heads advantage.

BTW watch out for the filter cartridge seals disintegrating,

On Thu, Jan 5, 2017 at 5:55 AM, Pete Turnbull  wrote:
> On 05/01/2017 13:22, Noel Chiappa wrote:
>>
>> > From: Klemens Krause
>>
>> > We clean our RK05 disks in a very robust way: with cheap burning
>> spirit
>> > and paper towels. ... We rubbed away thick black traces from
>> occasional
>> > head crashes and we never removed the oxide coating with this
>> torture.
>
>
>> First, what is 'burning spirit'? (I assume this is a straight translation
>> into English of some German term, but not knowing German... :-) After
>> poking
>> around with Google for a while (hampered no little by the fact that it's
>> the
>> name of a band, and also a term in World of Warcraft :-), it seems like it
>> might be acetone?
>
>
> I'm sure it's not ! :-)  He'll mean the sort of alcohol used in a spirit
> burner.  The UK equivalent is "methylated spirit" - primarily ethanol but
> with a (un)healthy dose of methanol to make it unfit to drink (and hence
> exempt from excise duty) plus pyridine (and small amounts of other things)
> to give it an unpleasant taste and odour, and some methyl purple dye to make
> it obvious at a glance.  Denatured alcohol, in other words. I don't think
> the German (EU) version has the dye although it does contain IPA and MEK.
> For cleaning, because of that dye, isopropyl alcohol (IPA, isopropanol) is
> often a better choice in the UK.
>
> In the US, "rubbing alcohol" is mostly denatured ethanol (though "isopropyl
> rubbing alcohol" is mostly IPA), but always contains other chemicals as
> well.  Either should do for cleaning a disk.
>
> --
> Pete
> Pete Turnbull
>

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Pete Lancashire]

My error did mean to say 90% just got a bit too wound up with so many
suggestions that could destroy the coating.

On Jan 5, 2017 7:49 AM, "Al Kossow"  wrote:

> 91% IPA works fine.
> 99% is better though i'm skeptical it really is
>
> https://www.quora.com/When-is-70-isopropyl-rubbing-alcohol-better-than-91
>
>
>
> >> In the US, "rubbing alcohol" is mostly denatured ethanol (though
> "isopropyl rubbing alcohol" is mostly IPA), but always contains other
> chemicals as well.
>
> https://www.lewisu.edu/academics/biology/pdf/isopropanol_91.pdf
>
> IPA
> Water
>
>
>
>

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[E. Groenenberg]

We have a similar common name for it being 'brand spiritus'.

It's basically 90% - 92% alcohol, with the rest being methanol and water
and it's color is blue-ish.

Ed
--
Ik email, dus ik besta.
BTC : 1J5fajt8ptyZ2V1YURj3YJZhe5j3fJVSHN
LTC : LP2WuEmYPbpWUBqMFGJfdm7pdHEW7fKvDz

On Thu, January 5, 2017 14:22, Noel Chiappa wrote:
> > From: Klemens Krause
>
> > We clean our RK05 disks in a very robust way: with cheap burning
> spirit
> > and paper towels. ... We rubbed away thick black traces from
> occasional
> > head crashes and we never removed the oxide coating with this
> torture.
>
> I am about to get a large batch of RK05 packs, so I am interested in the
> details of this.
>
> First, what is 'burning spirit'? (I assume this is a straight translation
> into English of some German term, but not knowing German... :-) After
> poking
> around with Google for a while (hampered no little by the fact that it's
> the
> name of a band, and also a term in World of Warcraft :-), it seems like it
> might be acetone?
>
>   Noel
>

RE: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Rick Bensene]

The method I've used very successfully for unknown packs is:

1) I first mount the pack in a drive that has a good absolute filter,
and has had the head load disabled, and spin it for a few hours.  If the
pack shows any sign of excessive vibration, it is probably no good or
requires more serious attention.   This process moves a bunch of air
through the pack, removing any loose dust.
2) I then take the pack apart, in a relatively dust-free space.  Inspect
the platter for any obvious damage that may make it unusable, such as
warping, mis-centered on hub (caused by being dropped), divots in the
platter surface or signs of serious head crash(e.g., oxide gone).   I
set the platter assembly on a lint-free cloth and cover with another
lint free cloth.
3) I first use a vacuum cleaner with a light brush attachment to vacuum
loose dust out of the pack case.  Then I use a sink with a sprayer head
and warm soapy water to thoroughly clean the plastic parts of the disk
pack, and rinse thoroughly with clear water.  I use dried compressed air
to blow out all the moisture, and then set the pack parts aside on a
lint-free cloth to dry out thoroughly, usually for 24 hours
4) I use 3M LCD monitor cleaning pads (which are lint-free by nature) to
wipe the platter surfaces to remove excess oxide and remaining dust.  I
use a light pressure.  Any areas that are clearly discolored get extra
treatment.  I wipe in a circular (spiral) motion from the hub outward to
the edge of the platters.  It's a little tedious from a handling
perspective, juggling the platter with one hand, and managing the wiping
with the other.  I end up using quite a few of the wipes, as they get
dirty pretty fast. 
5) I use a bright flashlight to spot any remaining dust and canned air
to dislodge any that I find.  If air doesn't work, then I use more wipes
to remove any that I can see.
6) Once over with canned air to blow off any remaining dust.
7) Quickly reassemble the patter into the pack casing 
8) Spin the pack again for  a few hours with no head load.
9) Cross fingers, put in a "live" drive, spin it up, and hope for no bad
noises.

Based on Klemens' method, this is probably being overly cautious, but
it's worked well for me. 

Rick Bensene

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[j...@cimmeri.com]

The method I use for RL02 packs (not sure if similar), is:

- remove platter from pack
- rinse it down with tap water
- apply some Simple Green to a microfiber cloth
- wipe the entire platter with that cloth
- rinse by wiping with a 2nd cloth wet with distilled water
- let dry 24 hours

John

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Kyle Owen]

The cleaning procedure in the laboratory I used to work in for removing
organics from silicon wafers was typically acetone, then isopropanol, then
ethanol, then a deionized water rinse and nitrogen dry. We did use piranha
solution on occasion when it was particularly caked on (like really old
photoresist). When I cleaned an ST-4051 in the lab, I skipped the acetone.
That worked quite well; the drive worked just fine after that (and a
low-level format).

Kyle

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Mouse]

>> In the US, "rubbing alcohol" is mostly denatured ethanol (though "isopropyl$

Interesting.  I don't think I've ever seen a bottle of "rubbing
alcohol" that was anything but isopropanol-and-water.  But I'm more
Canadian than US.

> I would suggest avoiding these blends of random chemicals made with no real $

Or, more precisely, with _different_ concern for purity.  For rubbing
alcohol you want to avoid biologically active contaminants, but
dissolved solids per se don't matter.  Here, you care about dissolved
solids but don't much care about things that might be biologically
active, as long as they evaporate without residue.

Which leads me to tentatively suggest gasoline (West Pondian) / petrol
(East Pondian), since it seems to me that will go to some lengths to
avoid fouling engines with residues.  And it's available pretty much
universally, and relatively cheaply.

Or am I wrong about it not leaving even trace residues?

Of course, anyone with distillation equipment could distil any of these
to get something with less residue.  But not everyone has chem-lab
glassware.

/~\ The ASCII Mouse
\ / Ribbon Campaign
 X  Against HTMLmo...@rodents-montreal.org
/ \ Email!   7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Al Kossow]

91% IPA works fine.
99% is better though i'm skeptical it really is

https://www.quora.com/When-is-70-isopropyl-rubbing-alcohol-better-than-91



>> In the US, "rubbing alcohol" is mostly denatured ethanol (though "isopropyl 
>> rubbing alcohol" is mostly IPA), but always contains other chemicals as well.

https://www.lewisu.edu/academics/biology/pdf/isopropanol_91.pdf

IPA
Water

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Paul Koning]

> On Jan 5, 2017, at 8:55 AM, Pete Turnbull  wrote:
> 
> On 05/01/2017 13:22, Noel Chiappa wrote:
>>> From: Klemens Krause
>> 
>>> We clean our RK05 disks in a very robust way: with cheap burning spirit
>>> and paper towels. ... We rubbed away thick black traces from occasional
>>> head crashes and we never removed the oxide coating with this torture.
> 
>> First, what is 'burning spirit'? (I assume this is a straight translation
>> into English of some German term, but not knowing German... :-) After poking
>> around with Google for a while (hampered no little by the fact that it's the
>> name of a band, and also a term in World of Warcraft :-), it seems like it
>> might be acetone?
> 
> I'm sure it's not ! :-)  He'll mean the sort of alcohol used in a spirit 
> burner.  The UK equivalent is "methylated spirit" - primarily ethanol but 
> with a (un)healthy dose of methanol to make it unfit to drink (and hence 
> exempt from excise duty) plus pyridine (and small amounts of other things) to 
> give it an unpleasant taste and odour, and some methyl purple dye to make it 
> obvious at a glance.  Denatured alcohol, in other words. I don't think the 
> German (EU) version has the dye although it does contain IPA and MEK.  For 
> cleaning, because of that dye, isopropyl alcohol (IPA, isopropanol) is often 
> a better choice in the UK.
> 
> In the US, "rubbing alcohol" is mostly denatured ethanol (though "isopropyl 
> rubbing alcohol" is mostly IPA), but always contains other chemicals as well. 
>  Either should do for cleaning a disk.

I recognized "burning spirit" by its Dutch analog, and yes, it means denatured 
ethanol.

I would suggest avoiding these blends of random chemicals made with no real 
concern for purity.  You need a liquid here that will evaporate cleanly, 
leaving behind neither oily residue nor solids.  I see no reason to believe 
that denatured alcohol or rubbing alcohol are made to those standards.

paul

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Al Kossow]

isopropyl alcohol works. TFE is better, if you have some stashed.

If you can find them anywhere, Texwipe made a plastic wand that looks like
a tongue depressor with a slit down the middle and a lint free sleeve
called the Texsleeve (tx300 sleeve, tx800 wand) that you would use to clean 
heads

Minor head crashes leave a tar-like residue that you need to remove. A pack 
inspector
is a handy thing to have (spinle with microscope and illuminator on the rack 
and pinion)
to look for surface damage.

On 1/5/17 5:22 AM, Noel Chiappa wrote:
> > From: Klemens Krause
> 
> > We clean our RK05 disks in a very robust way: with cheap burning spirit
> > and paper towels. ... We rubbed away thick black traces from occasional
> > head crashes and we never removed the oxide coating with this torture.
> 
> I am about to get a large batch of RK05 packs, so I am interested in the
> details of this.
> 
> First, what is 'burning spirit'? (I assume this is a straight translation
> into English of some German term, but not knowing German... :-) After poking
> around with Google for a while (hampered no little by the fact that it's the
> name of a band, and also a term in World of Warcraft :-), it seems like it
> might be acetone?
> 
>   Noel
> 

Re: Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Pete Turnbull]

On 05/01/2017 13:22, Noel Chiappa wrote:

> From: Klemens Krause

> We clean our RK05 disks in a very robust way: with cheap burning spirit
> and paper towels. ... We rubbed away thick black traces from occasional
> head crashes and we never removed the oxide coating with this torture.



First, what is 'burning spirit'? (I assume this is a straight translation
into English of some German term, but not knowing German... :-) After poking
around with Google for a while (hampered no little by the fact that it's the
name of a band, and also a term in World of Warcraft :-), it seems like it
might be acetone?


I'm sure it's not ! :-)  He'll mean the sort of alcohol used in a spirit 
burner.  The UK equivalent is "methylated spirit" - primarily ethanol 
but with a (un)healthy dose of methanol to make it unfit to drink (and 
hence exempt from excise duty) plus pyridine (and small amounts of other 
things) to give it an unpleasant taste and odour, and some methyl purple 
dye to make it obvious at a glance.  Denatured alcohol, in other words. 
I don't think the German (EU) version has the dye although it does 
contain IPA and MEK.  For cleaning, because of that dye, isopropyl 
alcohol (IPA, isopropanol) is often a better choice in the UK.


In the US, "rubbing alcohol" is mostly denatured ethanol (though 
"isopropyl rubbing alcohol" is mostly IPA), but always contains other 
chemicals as well.  Either should do for cleaning a disk.


--
Pete
Pete Turnbull

Cleaning RK05 packs (Was: LGP-30 Memory Drum Update)

[Noel Chiappa]

> From: Klemens Krause

> We clean our RK05 disks in a very robust way: with cheap burning spirit
> and paper towels. ... We rubbed away thick black traces from occasional
> head crashes and we never removed the oxide coating with this torture.

I am about to get a large batch of RK05 packs, so I am interested in the
details of this.

First, what is 'burning spirit'? (I assume this is a straight translation
into English of some German term, but not knowing German... :-) After poking
around with Google for a while (hampered no little by the fact that it's the
name of a band, and also a term in World of Warcraft :-), it seems like it
might be acetone?

Noel