11 Apr
2006
11 Apr
'06
10:46 a.m.
In a recent acquisition of several 11/23 systems I was fortunate to
receive four RL01
drives, being two sets of Unit 0 and Unit 1.
One set of these drives were very dirty/dusty, and by the looks of the
course filters
(which were deteriorating badly in all drives) and the accumulations in
the power
supply and plenum areas, I have to say this set was used in at least an
ISO Class 10
Million level (not so) clean room environment! The other drive set
was in
pretty good condition, cleanliness wise. I replaced all four course
filters, and
checked the absolute filters, which were actually okay even in the dirty
drives.
Because all of these have been powered off for many years, I opened them
up and
pulled the power supply for a session with my capacitor reformation rig
after
cleanup. With that successfully accomplished, and finding that all
voltages were in
line, everything was reassembled. During the wait for the capacitors, I
cleaned the
interior pretty well with a vacuum and Windex. As a side note, three of
the drives
still had the platter brushes installed, and since I already had each
drive opened
for power supply checkout, I went ahead and removed the brush assemblies.
Fortunately, the 'clean' set of drives are now fully functional, having
been tested
with one of the 11/23s.
Unfortunately, after mounting and LOADing a known good disk cartridge,
neither drive
from the 'dirty' set will show READY after
spinup. Though the details
are a bit
different, each drive emits a very noticeable sound, kind of a
whining/rumbling sound
(not squealing), that I think is indicative of dry bearings in the
spindle, the
spindle motor, or both. I wonder if dragging bearings are preventing
the drive from
becoming READY due to uneven RPM?
I've scoured the online documents for possible information regarding RL
drive
lubrication, but I can't come up with anything that suggests 'in the field'
lubrication options. The RL01/RL02 Maintenance Guide talks about
disassembly and
Field Replaceable Units, but nothing about lubrication.
So a few questions for those in the know:
Could dragging bearings be the cause of no READY indication?
Has anyone had any experience lubricating the appropriate assemblies in
an RL drive?
If so, what lubricant is recommended, where is it applied, and how?
Removing the motor for lubrication is no problem, but I wonder if
removing the
spindle assembly would then necessitate a head alignment once it's back
in place?
I'm not sure I'm ready to go through that process just yet! Still, if I
need to do
it, I need to do it.
Any advice is welcome.
Assuming I can get this resolved, I'm in the market for a set of (2) RL
connecting
cables and a terminator. Anyone with some spares that they'd like an
offer on,
please contact me off-list.
Thanks.
J
11 Apr
11 Apr
11:51 a.m.
pretty good condition, cleanliness wise. I replaced
all four course
filters, and
checked the absolute filters, which were actually okay even in the dirty
drives.
The RL airflow is rather nice in there's air circulated round the disk
pack, the absolute filter and the outside of the 'heat exchanger' tubes,
and a second airflow through the prefilter, the inside the of the tubes,
and out over the heatsinks and the PSU fan. While the first system is not
sealed, there is less interchange between it and the 'very dirty' air
than in most drives, so the absolute filters last longer.
Because all of these have been powered off for many years, I opened them
up and
pulled the power supply for a session with my capacitor reformation rig
after
cleanup. With that successfully accomplished, and finding that all
voltages were in
line, everything was reassembled. During the wait for the capacitors, I
cleaned the
interior pretty well with a vacuum and Windex. As a side note, three of
the drives
still had the platter brushes installed, and since I already had each
drive opened
for power supply checkout, I went ahead and removed the brush assemblies.
What did you remoce? Just the brush tips? Did you leave the motor, the
microswitch, and the operating cam? Without those, you might have
problems getting the drive to go ready.
Fortunately, the 'clean' set of drives are now fully functional, having
been tested
with one of the 11/23s.
Unfortunately, after mounting and LOADing a known good disk cartridge,
neither drive
from the 'dirty' set will show READY after spinup. Though the details
You do have these cabled to a working controller, I trust? You need the
clock signal from the cotnroller for the drive to spin up and go ready.
are a bit
different, each drive emits a very noticeable sound, kind of a
whining/rumbling sound
(not squealing), that I think is indicative of dry bearings in the
spindle, the
spindle motor, or both. I wonder if dragging bearings are preventing
the drive from
becoming READY due to uneven RPM?
It's possible, but unlikely. I suppose you could start by looking at the
output of the sector transducer (posibly after the amplifier circuit).
That's what the drive uses as a speed reference anyway (the motor in the
RL is not locked to the mains, unlike most other demountable hard drives,
there is no change for 50/60Hz). See if the signal is stable and has the
right frequency (compare it with the same signal in another working drive).
I've scoured the online documents for possible
information regarding RL
drive
lubrication, but I can't come up with anything that suggests 'in the field'
lubrication options. The RL01/RL02 Maintenance Guide talks about
disassembly and
Field Replaceable Units, but nothing about lubrication.
So a few questions for those in the know:
Could dragging bearings be the cause of no READY indication?
Has anyone had any experience lubricating the appropriate assemblies in
an RL drive?
I would not try to lubricate the spindle bearings. You'll never get it
apart anyway (t's pressed together, and you have to maintain mecahnical
balance, etc. There may be a ferrofluid seal in there too). The risk of
contamination to the disk/heads is too great.
It shouldn't hurt to take the spindle motor out, take it apart (obvious
through-bolts) and oil the bearings. I think they're phosphor-bronze
bushes, not ball races, in which case you want a medium machine oil on them.
If so, what lubricant is recommended, where is it
applied, and how?
Removing the motor for lubrication is no problem, but I wonder if
removing the
spindle assembly would then necessitate a head alignment once it's back
in place?
No, you can remove and replace the spindle without upseting the heads. In
any case, the RL drive has an embedded servo burst in each sector header,
so head alignemnt is quite easy (you need a 'scope, but no special
alignment disk, any normal disk will do).
-tony
12:41 p.m.
Tony Duell wrote:
Yes, I left the motor, cam, and switch. I just removed the actual brush
arm from the shaft, leaving everything else so that the logic would
'think' the brush is still in place.
Yes, indeed, I'm using the same platform for my testing of all drives --
both the dirty drives that are 'broken', and the clean set that work --
with every other component except the drive being the same. That is,
I'm using the same 11/23, RLV11 controller, cables, terminator, etc.
I'm just swapping the drives themselves.
Excellent advice. I will try this. I do have a scope, though I'm more
of a software geek rather than a hardware engineer! :) I just find it
interesting that both of these drives (the 'dirty' set) exhibit the same
behavior vs. the 'clean' set, when all else is the same, i.e.,
controller, etc. I may be fixating on the noise as the cause of no
READY indication, but maybe it's something else.
for power
supply checkout, I went ahead and removed the brush assemblies.
What did you remoce? Just the brush tips? Did you leave the motor, the
microswitch, and the operating cam? Without those, you might have
problems getting the drive to go ready.
Fortunately, the 'clean' set of drives are now fully functional, having
been tested
with one of the 11/23s.
Unfortunately, after mounting and LOADing a known good disk cartridge,
neither drive
from the 'dirty' set will show READY after spinup. Though the details
You do have these cabled to a working controller, I trust? You need the
clock signal from the cotnroller for the drive to spin up and go ready.
I wonder if dragging bearings are preventing
the drive from
becoming READY due to uneven RPM?
It's possible, but unlikely. I suppose you could start by looking at the
output of the sector transducer (posibly after the amplifier circuit).
That's what the drive uses as a speed reference anyway (the motor in the
RL is not locked to the mains, unlike most other demountable hard drives,
there is no change for 50/60Hz). See if the signal is stable and has the
right frequency (compare it with the same signal in another working drive).
I would not try to lubricate the spindle bearings. You'll never get it
apart anyway (t's pressed together, and you have to maintain mecahnical
balance, etc. There may be a ferrofluid seal in there too). The risk of
contamination to the disk/heads is too great.
Hmm...okay. I'll let this go for now, hoping that the issue is with
the motor.
It shouldn't hurt to take the spindle motor out,
take it apart (obvious
through-bolts) and oil the bearings. I think they're phosphor-bronze
bushes, not ball races, in which case you want a medium machine oil on them.
I'll begin here, and see if this resolves the noises I'm hearing. I
still hope that IF the lubrication helps to steady the RPM, it might let
the drives go READY.
No, you can remove and replace the spindle without
upseting the heads. In
any case, the RL drive has an embedded servo burst in each sector header,
so head alignemnt is quite easy (you need a 'scope, but no special
alignment disk, any normal disk will do).
I was just worried that there might be some vertical alignment issues if
the spindle assembly wasn't put back correctly. I have no idea if there
are shimming or 'leveling' screws that would assist in making sure that
the platter is aligned vertically (along its axis) so that the heads
have the proper 'flying height' for both surfaces of the platter.
Many thanks, Tony, for you suggestions. I'll let you know how it goes,
probably later in the week. I've gotta satisfy the tax man first!
April 17 is fast approaching! :)
J.
2:54 p.m.
Tony Duell wrote:
Yes, I left the motor, cam, and switch. I just removed the actual brush
arm from the shaft, leaving everything else so that the logic would
'think' the brush is still in place.
Sorry if some of my questions were 'going over the bleeding obvious'...
All too often I've found I've made assumptions about what the other chap
has or has not done, and wasted a lot of time going along the wrong path.
for power
supply checkout, I went ahead and removed the brush assemblies.
What did you remoce? Just the brush tips? Did you leave the motor, the
microswitch, and the operating cam? Without those, you might have
problems getting the drive to go ready.
It's
possible, but unlikely. I suppose you could start by looking at the
output of the sector transducer (posibly after the amplifier circuit).
That's what the drive uses as a speed reference anyway (the motor in the
RL is not locked to the mains, unlike most other demountable hard drives,
there is no change for 50/60Hz). See if the signal is stable and has the
right frequency (compare it with the same signal in another working drive).
Excellent advice. I will try this. I do have a scope, though I'm more
of a software geek rather than a hardware engineer!
:) I just find it
interesting that both of these drives (the 'dirty' set) exhibit the same
behavior vs. the 'clean' set, when all else is the same, i.e.,
controller, etc. I may be fixating on the noise as the cause of no
READY indication, but maybe it's something else.
Another 'obvious' question : You have made sure the head lock is not
fitted on the 'dirty drives'? That would stop it going ready.
I'll begin here, and see if this resolves the
noises I'm hearing. I
still hope that IF the lubrication helps to steady the RPM, it might let
the drives go READY.
I think there's some kind of grounding brush on the spindle, visible
under the little cover on the bottom of the drive. That can, I suspect,
make odd noises, but it shouldn't stop the thing going ready.
No, you can
remove and replace the spindle without upseting the heads. In
any case, the RL drive has an embedded servo burst in each sector header,
so head alignemnt is quite easy (you need a 'scope, but no special
alignment disk, any normal disk will do).
I was just worried that there might be some vertical alignment issues if
the spindle assembly wasn't put back correctly. I have no idea if there
are shimming or 'leveling' screws that would assist in making sure that the platter is aligned vertically (along its axis) so
that the heads
have the proper 'flying height' for both surfaces of the platter.
-tony
3:38 p.m.
Tony Duell wrote:
No worries. It's good to have someone look over my shoulder helping to
make sure I'm not my usual complete idiot! :) Thanks!
I think the printset is on Bitsavers (if not, I have it). If you can't
find the right point to look at this signal, let me know, I'll get out
the prints and tell you what pin of what IC to look at.
I'll check bitsavers. If I can't find what I need, I'll come back
to you.
Well, this is good news, at least. I hope not, but I may end up
removing the spindle eventually, and this let's me be more comfortable
about that possibility.
Again, thanks for the advice, Tony. It might be a day or two for me to
get back to this project, but I'll post my results as they are gathered.
J.
Yes, I left
the motor, cam, and switch. I just removed the actual brush
arm from the shaft, leaving everything else so that the logic would
'think' the brush is still in place.
Sorry if some of my questions were 'going over the bleeding obvious'...
All too often I've found I've made assumptions about what the other chap
has or has not done, and wasted a lot of time going along the wrong path.
See if the signal is stable and has the
right frequency (compare it with the same signal in another working drive).
Excellent advice. I will try this. I do have a scope, though I'm more
Another 'obvious' question : You have made
sure the head lock is not
fitted on the 'dirty drives'? That would stop it going ready.
Another valid question. Yes, indeed, the head/actuator locking plate
has been rotated to the 'un-locked' position. This might be the place
to mention that these two 'dirty' drives had the heads already locked at
the time of acquisition. I'm doubtful that they have been used in many,
many years, since this indicates that the former owner had not tried them.
I wonder....could the heads, having been in the retracted position for
so long (years and years), be kind of 'glued' in place by dust/grime/dry
grease, thus no READY indication? Hmm...a question: is it advisable to
move the heads manually to test this, or am I better off keeping my fat
fingers out of the head actuator area (which I've religiously done to date)?
I think there's some kind of grounding brush on
the spindle, visible
under the little cover on the bottom of the drive. That can, I suspect,
make odd noises, but it shouldn't stop the thing going ready.
This, too, is a good point. I do recall reading about the grounding
'point' in the Maintenance Manual. I'll check this also.
I was just
worried that there might be some vertical alignment issues if
the spindle assembly wasn't put back correctly. I have no idea if there
are shimming or 'leveling' screws that would assist in making sure that
There are no leveling screws, and AFAIK no shims either. Vertical
alignment is not _too_ critical -- the heads fly rememebr, so will align
themselves to the platter surface. I think all you have to do is make
sure the mounting faces on the chassis and spindle housing are clean, put
the spindle in place and tighten the screws evenly.
12 Apr
12 Apr
2:55 p.m.
Sorry if some
of my questions were 'going over the bleeding obvious'...
All too often I've found I've made assumptions about what the other chap
has or has not done, and wasted a lot of time going along the wrong path.
No worries. It's good to have someone look over my shoulder helping to
make sure I'm not my usual complete idiot! :) Thanks! See if the
signal is stable and has the
right frequency (compare it with the same signal in another working drive).
Excellent advice. I will try this. I do have a scope, though I'm more
From memory, there are 3 versions of the logic board
used in the RL01.
The first oen is RL01-only, the other 2 can be used either in an
RL01 or
an RL02 with a jumper change. The last of those has many more testpoints
than the earlier one.
There are significant electronic differences between the first one and
the other 2. My RL01 printset only covers the first version, for the
others I look at the RL02 printset.
The pocket service guide (is that on Bitsavers?) is probably the best
reference to tell the boards apart. I have that that booklet too, and can
tell you what to look for if you have problems.
Another 'obvious' question : You have
made sure the head lock is not
fitted on the 'dirty drives'? That would stop it going ready.
Another valid question. Yes, indeed, the head/actuator locking plate
has been rotated to the 'un-locked' position. This might be the place
to mention that these two 'dirty' drives had the heads already locked at
the time of acquisition. I'm doubtful that they have been used in many,
many years, since this indicates that the former owner had not tried them.
I wonder....could the heads, having been in the retracted position for
so long (years and years), be kind of 'glued' in place by dust/grime/dry
grease, thus no READY indication? Hmm...a question: is it advisable to move the heads manually to test this, or am I better
off keeping my fat
fingers out of the head actuator area (which I've religiously done to date)?
What you want to avoid is touching the heads themselves (obviously) or
letting the heads touch each other. What I would do is put a clean,
folded, lens tissue between the head 'buttons', then carefully move the
carriage towards the spindle. Try to keep the heads on the loading ramp,
but the tissue should prevent any damage if you can't.
-tony
5:37 p.m.
Tony Duell wrote:
yup. I was just looking at this today.
54-12175 RL01
54-13531 v2 (RL01 or RL02)
54-14025 v3
I don't know about the v3 board. It may do them both also.
I ended up with an RL02 today with no drive logic module and no fan.
Everything else looks ok.
If anyone has a RL02 V2 or V3 drve logic module they would part with,
please let me know.
(I'm also on the hunt for rk05 parts)
-brad
From memory, there are 3 versions of the logic
board used in the RL01.
The first oen is RL01-only, the other 2 can be used either
in an RL01 or
an RL02 with a jumper change. The last of those has many more testpoints
than the earlier one.
13 Apr
13 Apr
11:13 a.m.
From memory, there are 3 versions of the logic board
used in the RL01.
The first oen is RL01-only, the other 2 can be used either in an
RL01 or
an RL02 with a jumper change. The last of those has many more testpoints
than the earlier one.
1:15 a.m.
Tony Duell wrote:
I have one of the older type, and the other three are of the new type.
But, turns out that it doesn't matter anymore, in terms of which
printset to use, since I think I have resolution to both drives'
problems (more below).
Okay, here's the good stuff you've been waiting for. Just to recap:
Drive 0 would not show READY. Trying to read from it anyway with RT11,
gave a 'drive not responding' kind of message (don't have the exact text
in front of me at the moment). And it put out a fair amount of
whining/rumbling when spun up.
Drive 1 would not show READY. (here's where I was brainless) I never
actually tried to read this drive, since I never saw READY (I was
already 'conditioned' by what I saw with Drive 0). This drive, too, put
out a significant whine as it spun.
Here's what I did:
I opened each drive up, and did two things to each: 1) With the upper
and lower head 'trays' propped apart, I manually exercised the r/w head
carriage, moving it back and forth a number of times, and 2) I put a
couple of drops of oil on the top of each motor's shaft, which was
easily reached with the service cover off.
Interestingly, Drive 0's head carriage *did indeed* have some fair
resistance to motion when I first tried to move it. As I exercised it a
few times it loosened up and moved pretty well after about a dozen full
travel cycles. I actually believe this was a problem. If the heads
couldn't budge, certainly the drive wouldn't come READY. I guess the
lubrication on the rails or the pull cable cylinder (or whatever it is
called) were somewhat gummed up. I didn't apply any additional
lubrication, since it loosened up pretty well after a few cycles, and I
didn't want to introduce into this area anything that wasn't according
to spec (whatever that may be).
Drive1's head carriage didn't show much resistance to motion when I
manually exercised it. This was useful information to me since it gave
me a sort of benchmark of comparison for what I experienced with Drive 0.
So, the bottom line:
Drive 0, having been reconnected to the 11/23, still didn't show READY,
but I *was* able to talk to it. I even went so far as to image a whole
disk cartridge to my PC without difficulty. Checking the READY
indicator bulb, I discovered the bulb was burned out. Duh! (I told you
I was partially brainless during this whole episode.) However, after
replacing the bulb with a new one (I have a supply for just this
purpose), I still don't get a READY light. More to look into, but the
drive now actually works!
Drive 1, also works just fine. (Uh, oh, more brainless-ness ahead...)
It, too, had a burned out bulb! And since I never actually tried to
read from this drive, after having no luck from Drive 0 (which had the
same symptoms at the time), I just assumed it was broken too. It was
probably only a bad bulb all along. A replacement bulb gave me a nice
READY indication. How stupid is that!?
The good news from going through this whole process is that I believe
the small amount of lubrication that I applied to both drives' motors
did the trick. Each drive is now quiet, at least as quiet as RL drives
usually are.
I *do* believe that the head carriage of Drive 0, was stuck, but it's
hard to prove it. It, the whole drive, works now (sans READY light),
and that's a whole lot better than a few days ago. I do think that a
bit of lubrication to the drives' motors was definitely useful.
I'll keep working on the Drive 0 READY indicator light. Probably some
broken or loose contact in the switch itself, or the front panel switch
assembly. I'll pull that and check everything.
Thanks for all of your input, Tony!
J.
I could tell you many stories of times when I've
spent hours looking for
a fault only to find I've not plugged it into the mains, or there's no
fuse in the plug, or....
Well, as it turns out, I *was* partially brainless with this episode
(more below).
From memory,
there are 3 versions of the logic board used in the RL01.
The first oen is
RL01-only, the other 2 can be used either in an RL01 or
an RL02 with a jumper change. The last of those has many more testpoints
than the earlier one.
There are significant electronic differences between the first one and
the other 2. My RL01 printset only covers the first version, for the
others I look at the RL02 printset.
The pocket service guide (is that on Bitsavers?) is
probably the best
reference to tell the boards apart. I have that that booklet too, and can
tell you what to look for if you have problems.
Yes, I do have a copy of the pocket service guide, thanks to bitsavers.
Again, no longer required (more below), but very handy to have around.
I have already benefited from it.
I
wonder....could the heads, having been in the retracted position for
so long (years and years), be kind of 'glued' in place by dust/grime/dry
grease, thus no READY indication? Hmm...a question: is it advisable to
It's possible.
4:04 a.m.
J Blaser wrote:
I opened each drive up, and did two things to each: 1) With the upper
and lower head 'trays' propped apart, I manually exercised the r/w head
carriage, moving it back and forth a number of times, and 2) I put a
couple of drops of oil on the top of each motor's shaft, which was
easily reached with the service cover off.
I'm curious if anyone has done something similar with an RK05.
Certainly the bearings can be replaced, but can they also be cleaned and
relubricated? is it safe to pull the entire voice coil assembly apart,
clean the bearings and tracks, relubricate and reassemble?
any suggestions? thx.
-brad
11:32 a.m.
I'm curious if anyone has done something similar
with an RK05.
Certainly the bearings can be replaced, but can they also be cleaned and
relubricated? is it safe to pull the entire voice coil assembly apart,
clean the bearings and tracks, relubricate and reassemble?
For the RK05, the maintenance manual gives a procedure for replacing the
carriage bearings, and I think the IPB manual gives an exploded diagram
and parts list for the voice coil positioner. Therefore it was regarded
as possible to dismantle it in the field and replace parts.
I am pretty sure the bearings are standard parts. It may be better to
replace them, I wound't want to risk luvricant getting onto the disk or
heads. But actually you should be alright taking the covers off the
bearings and lubrigating them (I would guess a light grease is the stuff
to use here).
If you dismantle the positioner, be warned that about the first thing you
have to do is remove the heafs. Which means you'll need an alignment pack
to get it back together again.
-tony
11:28 a.m.
Tony Duell wrote:
I know that feeling _very_ well :-)
I could tell you many stories of times when
I've spent hours looking for
a fault only to find I've not plugged it into the mains, or there's no
fuse in the plug, or....
Well, as it turns out, I *was* partially brainless with this episode The pocket
service guide (is that on Bitsavers?) is probably the best
reference to tell the boards apart. I have that that booklet too, and can
tell you what to look for if you have problems.
Yes, I do have a copy of the pocket service guide, thanks to bitsavers.
Interestingly, Drive 0's head carriage *did
indeed* have some fair
resistance to motion when I first tried to move it. As I exercised it a
few times it loosened up and moved pretty well after about a dozen full
travel cycles. I actually believe this was a problem. If the heads
FWIW, I've never tried to dismantle and reassemble an RL positioner, so I
don't know how hard it would be, and even if it's possible (all the DEC
manuals seem to suggest replacing it as a unit, alas). Maybe I should
sometime (I've got a MINC with a pair of RL01s that's not doing anything
much, I wouldn't worry too much if I couldn't reassemble it).
couldn't budge, certainly the drive wouldn't
come READY. I guess the
lubrication on the rails or the pull cable cylinder (or whatever it is
IIRC, there's a permanent magnet DC motor that turns that cable drum.
Maybe its bearings were gummed up or something.
Drive 0, having been reconnected to the 11/23, still
didn't show READY,
but I *was* able to talk to it. I even went so far as to image a whole
disk cartridge to my PC without difficulty. Checking the READY
indicator bulb, I discovered the bulb was burned out. Duh! (I told you
Argh!
I was partially brainless during this whole episode.)
However, after
replacing the bulb with a new one (I have a supply for just this
purpose), I still don't get a READY light. More to look into, but the
drive now actually works!
Well, there can't be much wrong with it, then. I am pretty sure the fact
that it works means that the internal ready signal is going active. So
it's either the lamp driver chip (on the logic board I think), the cable,
lamp holder, soemthiog like that.
-tony
11:55 a.m.
Drive 0,
having been reconnected to the 11/23, still didn't show READY,
but I *was* able to talk to it. I even went so far as to image a whole
disk cartridge to my PC without difficulty. Checking the READY
indicator bulb, I discovered the bulb was burned out. Duh! (I told you
Argh!
6829
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6831
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12 comments
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ard＠p850ug1.demon.co.uk -
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