25 Feb
2014
25 Feb
'14
10:06 p.m.
I recently acquired 3 RK05j's that seem to have spent time in a barn as
well as having been used by a heavy smoker. I thoroughly cleaned and
de-gray-foamed them as well as putting in new absolute filters.
The first one came up after cleaning with no issues. Works great.
Number two spins up but the initial seek emits a sickening "klang" as the
voice coil drives hard to the limit (yes, the graticule lamp is working).
Any ideas?
The third drive initially had really ugly heads that never cleaned up to my
liking. I loaded a disk anyway and for about 5 seconds after the initial
head load all was okay. Then I heard the sound of the top head scouring
the disk.
So I'm thinking of buying replacement heads off of eBay. Apparently these
are the heads but not the steel tongues that they mount on.
So I have some questions for anyone on the list who may have changed their
heads.
1. How hard is it to mount the head in the tongue? Looks like just 2
screws.
2. How hard is it to remove/replace the tongue assembly? Looks like it
mounts with a couple of allen screws.
3. How hard is it to align the heads? I don't have a CE pack so I'll just
have to use a pack that works okay on the other drive.
4. Any sage advice or whatever?
Thanks for any and all help.
Marc
26 Feb
26 Feb
2:36 a.m.
On Tue, 25 Feb 2014, Marc Howard wrote:
Number two spins up but the initial seek emits a
sickening "klang" as the
voice coil drives hard to the limit (yes, the graticule lamp is working).
Any ideas?
Check the "Cylinder Address and Difference" board. Most likely it is
faulty.
The third drive initially had really ugly heads that
never cleaned up to my
liking. I loaded a disk anyway and for about 5 seconds after the initial
head load all was okay. Then I heard the sound of the top head scouring
the disk.
How did you clean the head? Usually, with enough patience (can be half an
hour or more), you'll get them clean anyway.
1. How hard is it to mount the head in the tongue?
Looks like just 2
screws.
I'd say practically impossible. At least I've never heard of someone doing
this in the field.
2. How hard is it to remove/replace the tongue
assembly? Looks like it
mounts with a couple of allen screws.
That's easy.
3. How hard is it to align the heads? I don't
have a CE pack so I'll just
have to use a pack that works okay on the other drive.
You'll definitely need a scope and the maintenance manual. Without scope,
you won't find the center of a track.
Christian
4:44 a.m.
Check the "Cylinder Address and Difference"
board. Most likely it is
faulty.
BTW: Repairing RK05 is usually real fun and not much frustration :-)
How did you clean the head? Usually, with enough
patience (can be half
an hour or more), you'll get them clean anyway.
I use a match (the *wooden*
side!!!) or similar in conjunction with ipa
to get the crusts off. In the end I use some tissue with IPA to clean
the heads.
1. How hard is
it to mount the head in the tongue? Looks like just 2
screws.
I'd say practically impossible. At least I've never heard of someone
doing this in the field. 
5:29 a.m.
On Feb 26, 2014, at 7:44 AM, Philipp Hachtmann <hachti at hachti.de> wrote:
...
Matches are wax-soaked wood, so that doesn?t seem like an ideal choice. Tongue depressors
might be better. Or you could go to a tool supply company and find orange wood sticks,
those seem to be intended for this sort of job.
Windex works very well for taking off tobacco smoke residue. And I like laquer thinner as
a universal solvent for tough jobs. For any cleaner, especially potent ones like laquer
thinner, you?d want to check first that it doesn?t attack the surface in question.
paul
How did you clean the head? Usually, with enough
patience (can be half
an hour or more), you'll get them clean anyway.
I use a match (the *wooden*
side!!!) or similar in conjunction with ipa to get the crusts off. In the end I use some
tissue with IPA to clean the heads.
9:17 a.m.
On Wed, 26 Feb 2014, Paul Koning wrote:
Matches are wax-soaked wood, so that doesn?t seem like
an ideal choice.
?? No, matches are plain wood, no wax or anything else. But I have no idea
what you can buy in the US.
Windex works very well for taking off tobacco smoke
residue. And I like
The best is Sidol plastic cleaner. *That* really takes tobacco (nicotine)
off immediately as it contains ammonia. But that's not what you usually
find on a head surface.
laquer thinner as a universal solvent for tough jobs.
For any cleaner,
especially potent ones like laquer thinner, you?d want to check first
that it doesn?t attack the surface in question.
Laquer thinner usually contains organic solvents, and that you really
don't want to rub into the head gap or on plastic parts. Use alcohol,
nothing else.
Christian
9:49 a.m.
On Feb 26, 2014, at 12:17 PM, Christian Corti <cc at informatik.uni-stuttgart.de>
wrote:
On Wed, 26 Feb 2014, Paul Koning wrote:
Waterproof matches (the kind you would use for camping) are often coated
and/or soaked with wax. Normal kitchen matches are just dry wood here,
though.
- Dave
Matches are wax-soaked wood, so that doesn?t seem
like an ideal choice.
?? No, matches are plain wood, no wax or anything else. But I have no idea what you can
buy in the US. 
10:05 a.m.
Matches are
wax-soaked wood, so that doesn?t seem like an ideal
choice.
?? No, matches are plain wood, no wax or anything else. But I have
no idea what you can buy in the US. Laquer thinner usually contains organic solvents, and
that you really
don't want to rub into the head gap or on plastic parts. Use
alcohol, nothing else.
What are "organic solvents" here? Alcohols - ethanol, isopropanol, or
whatever - are generally considered organic from a chemical point of
view; they are carbon-backbone compounds, after all.
/~\ The ASCII Mouse
\ / Ribbon Campaign
X Against HTML mouse at rodents-montreal.org
/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
11:23 a.m.
On Wed, 26 Feb 2014, Mouse wrote:
Actually, over here, wooden matches are typically
plain wood for much
of their length, but there is some wax soaked into the business end so
they act a little like a candle briefly after being struck. This
prevents them from burning back from the end too fast (ie, the flame
stays right at the end for a little); I assume that's why it's done.
When camping, a wax coating of the "business end" keeps dampness from
ruining the matches.
11:02 a.m.
Windex works very well for taking off tobacco smoke
residue. And I
like laquer thinner as a universal solvent for tough jobs. For any
cleaner, especially potent ones like laquer thinner, you?d want to check
first that it doesn?t attack the surface in question
IIRC the heads in these drives are mounted in ceramic disks. They are
unlikely to eb attacked by any common solvents. The main risk is leaving
a residue behind.
FWIW, Iv'e never had a head that couldn't be clened u pwith propan-2-ol,
althoguht it is often easier to remvoe the head and put it o nteh bench
rather htna to try to work between the 2 heads mounted on the positioner.
-tony
10:49 a.m.
So I have some questions for anyone on the list who
may have changed their
heads.
I have replaced RK05 heads, but I had the proper DEC spare part (:-))
complete with the leaf spring/mounting strip.
1. How hard is it to mount the head in the tongue? Looks like just 2
screws.
I think that's right. I assuem the screws go into threaded bushes in the
ceramic disk, so you ened ot be very careful when tightening them. I also
wonder if there's enouygh free play in thge mounting holes to mean the
head azimuth (angle between the gap and the track, basically) will not
necessarily be corrrect. Setting that could be 'interesting'.
2. How hard is it to remove/replace the tongue
assembly? Looks like it
mounts with a couple of allen screws.
There are 2 allen setscrews per head. One clamps the head assembly, the
other is used to push the head towards the spindle,. When fitting a new
head, you start wit hthe second oen beacked off, then slide in the head.
Put in the alignment disk, seek to the right cylinder and carefully screw
i nthe adjusting screw until the lobes on the 'scope screen are the same
size. If you go too far you ahve to unload the heads, push the head back
by hand, then try again. Actually, it's not that hard.
I recoment gettting the RK05 maintenance manual, I guess it's on
bitsavers. There is a warning that these screws go into a fairly soft
alloy casting, and it's possible to strip the threads. There is an
official torque setting, but I guess very few peoplehave a torque wrench
that goes down that low
On other thing. The leaf springs force the heads onto the disk, and thus
towards each other. Wehn fitting or removign a head, make sure they don't
suddenly srpign together, or you may damage the face of the enw head.
It's a good idea to fit the shippling lock o nthe positioner to hold the
carriage back when your are ahdnlign the heads. It's one less thing to
move about.
3. How hard is it to align the heads? I don't
have a CE pack so I'll just
have to use a pack that works okay on the other drive.
I have the EE pack... With that it's quite easy. I susepct you could
align for peak output or something like thwt. Maybe putt in the
known-good pack, then scre in the adjusting screw whilecounting the turns
and noticing when the amplitude starts to rise and when the signal
vanishes again. Then start again,m note where the amplitde starts to rise
and screw in half as many turns as it took for the amplitude ot flal off.
That should get the head over the middle of the track.
I don't know how weay it would be, but if possible, start witha
bulk-erased pack (rememebr, no servo information on these disks) and
format one cylinder (knowing which oen it is!). Then set up on that. This
will avoid gettign the heads aligned on the wrong cylinder.
-tony
3:05 p.m.
A few extra notes on my original post:
The reason I asked about changing the head pads was that there's someone on
eBay selling the pads for $95 + extra for mounting. I hate the idea of
sending out my head mounts just because I don't have a torque screwdriver
calibrated in femto Newtons.
Does any know of any other current source for head assemblies? The only
ones I've found don't list prices on their webpages. Ditto for CE packs.
"Quote" usually means "bend over".
As for cigarette smoke, that was somewhat of a joke. However the heads do
have thick black streaks, probably from that damn black foam. I tried for
about 15 minutes to clean them up with chamois head swabs soaked in 99.9%
isopropyl alcohol. I'll try to spend some more time + use a wooden tongue
depressor later when I get some more time. Unfortunately the problem head
is the top head. I really wish it could be buffed with a Dremel tool.
Marc
3:46 p.m.
On 2/26/2014 3:05 PM, Marc Howard wrote:
As for cigarette smoke, that was somewhat of a joke.
However the heads do
have thick black streaks, probably from that damn black foam. I tried for
about 15 minutes to clean them up with chamois head swabs soaked in 99.9%
isopropyl alcohol. I'll try to spend some more time + use a wooden tongue
depressor later when I get some more time. Unfortunately the problem head
is the top head. I really wish it could be buffed with a Dremel tool.
I don't
know about this specific drive but with the top loading 2.5mb
14" Dynex and Microdata drives, we would sometimes take crashed scrap
heads and clean them up and check them a magnifying glass to see how the
heads looked, and reuse them in junk test drives.
I don't know if the drives in some of these systems that survive are
primary customer pristine systems, or perhaps have some bits and pieces
of the above type parts added. The black streaks on the heads we had
sometimes took a lot of work to clean up, but the damage was from a
crash, not from foam. And they typically worked fine. just not what
you wanted to bet your enterprise on, if you will, but fine for a test lab.
jim
5:19 p.m.
On 02/26/2014 03:05 PM, Marc Howard wrote:
As for cigarette smoke, that was somewhat of a joke.
However the heads do
have thick black streaks, probably from that damn black foam. I tried for
about 15 minutes to clean them up with chamois head swabs soaked in 99.9%
isopropyl alcohol. I'll try to spend some more time + use a wooden tongue
depressor later when I get some more time. Unfortunately the problem head
is the top head. I really wish it could be buffed with a Dremel tool.
You might want to try some Freon TF, if you have a source--that was the
most common universal solvent for this kind of stuff before it got
banned. I don't know if there's a comparable HCFC cleaner. You may
also want to consider butane.
Short of that, locate some auto brake cleaner using perchloroethylene as
the active ingredient. Keep it off of plastic--it's only moderately
reactive with most plastics, but better to be safe than sorry. A brand
that I use is called "Brakleen".
I've cleaned very stubborn deposits from floppy heads using it. Take
appropriate precautions--you don't want to sniff the stuff.
Of course, it may be banned in your location--I believe it is in some
California cities.
Seems like anything useful is illegal or controlled. The local hardware
stores in town don't sell MEK because apparently it's used as a solvent
in making methamphetamine. However, go to a town five miles down the
highway and it's readily available. Go figure.
FWIW,
Chuck
27 Feb
27 Feb
12:46 p.m.
A few extra notes on my original post:
The reason I asked about changing the head pads was that there's someone on
eBay selling the pads for $95 + extra for mounting. I hate the idea of
sending out my head mounts just because I don't have a torque screwdriver
calibrated in femto Newtons.
There is no torque settign given for the haead-to-spring arm screws, for
the simple reason that you ere never expected to remove thos. The torque
setting is for the clamping allen setscrew in the carriage. To be fair,
it;'s nto that critical. I _do_ have a torque wrench that goes down that
low, but I nave never used it for this.It's just worth knowign that the
thing is fairly fragile and not to swing on the end of the allen key.
As I mentiuoned, my main worry would be getting the head disk aligned on
the leaf spring. If it is rotated slightly, the azimuth will be off, and
I think there will be enough free play in the screw holes for that to be a
problem.
-tony
26 Feb
26 Feb
3:59 p.m.
New subject: TSX-Plus mutiuser OS for pdp11
Hello All,
I found an old message in this list written 9 years ago by Mr. Lyle Bickley. He had
announced that possible in the future the TSX Plus distribution will be available for
hobbyists from his site. Does anyone know if mentioned kit was available ever since then
in any form?
Andrey
27 Feb
27 Feb
1:05 p.m.
New subject: TSX-Plus mutiuser OS for pdp11
To all CC list folks:
On Thu, 27 Feb 2014 02:59:17 +0300
Andriy Romanenko <bigral at hotmail.com> wrote:
Hello All,
I found an old message in this list written 9 years ago by Mr. Lyle
Bickley. He had announced that possible in the future the TSX Plus
distribution will be available for hobbyists from his site. Does
anyone know if mentioned kit was available ever since then in any
form?
Andrey
As with anyone who contacts me as a hobbyist. I gave Andriy
private FTP access to TSX Plus.
I'm in the process (this week) of working with S&H (owners of TSX) to
allow me to post TSX to my website with public access - without having
to vet every request.
My sense is that will happen.
Regards,
Lyle
--
Bickley Consulting West Inc.
http://bickleywest.com
"Black holes are where God is dividing by zero"
26 Jun
26 Jun
2:29 p.m.
New subject: TSX-Plus mutiuser OS for pdp11
On 2/27/2014 1:05 PM, Lyle Bickley wrote:
As with anyone who contacts me as a hobbyist. I gave
Andriy private
FTP access to TSX Plus. I'm in the process (this week) of working with
S&H (owners of TSX) to allow me to post TSX to my website with public
access - without having to vet every request. My sense is that will
happen. Regards, Lyle
Hi there,
Was warming up my PDP-11 for this summer's Retrochallenge, and wondering
how the TSX Plus website process was coming along. It would be great to
have access to the bits!
Thanks,
- Earl
26 Feb
26 Feb
10:52 a.m.
Missed this first time round.
Number two spins up but the initial seek emits a
sickening "klang" as the
voice coil drives hard to the limit (yes, the graticule lamp is working).
Any ideas?
It sounds (!) like a problem with the oprtical trasnducer (the thing the
the graticule lamp shines on) or the servo circuitry. What I would do is
disable the servo (red swtich on th amplifier PCB on top of the PSU), put
a folded imwipe between the heads and disable interlocks so the drive wil
lrun without a disk instaleld. Then move the carriage frowards by hand
wit hthe thing effectively spun up (the Kimwipe wil lavoid damaging the
heads) and look at the signals i nthe positioner servo circuit with a
'scope. Start wit hthe outputs of the transducer, see if all signals are
present and change as you move the carriage.
-tony
27 Feb
27 Feb
3:39 a.m.
What I would do is
disable the servo (red swtich on th amplifier PCB on top of the PSU), put
a folded imwipe between the heads and disable interlocks so the drive wil
lrun without a disk instaleld. Then move the carriage frowards by hand
wit hthe thing effectively spun up (the Kimwipe wil lavoid damaging the
heads) and look at the signals i nthe positioner servo circuit with a
'scope. Start wit hthe outputs of the transducer, see if all signals are
present and change as you move the carriage.
I do it the same way - but with a spinning disk in the drive. It comes
out the same...
Ph
11:25 a.m.
Sometimes you need to take a leap of faith to go forward.
Last night I cleaned the hell out of both the heads and the disk pack. I
even tried Brakekleen on the leading surface of the bottom head but it
didn't remove anything. I had the best results with putting lint free
cloth soaked in 99.9% isopropyl alcohol between the loaded heads. Got the
top head clean except for a wide line somewhat less than 0.1" wide that
goes from top to bottom. It's so perfect it looks like the head was
somehow made that way. Bottom head only had a few small blemishes left.
The disk pack had a wide scour mark with a few very small black areas. I
never could get this any cleaner.
Anyway, I fired up the drive and got the slight crashing noise again. I
re-cleaned the heads and decided to try a known good pack. Success! No
noise. I can DIR the drive and it looks good. Now I can either work on
the clanging 3rd drive or go back to TC08 debugging.
BTW, I saw a reference in another thread to using FUTIL's SCAN command to
do a simple disk read check. I can't get it to work. Does anyone here
know the correct syntax, etc for this?
Thanks again,
Marc
On Thu, Feb 27, 2014 at 3:39 AM, Philipp Hachtmann <hachti at hachti.de> wrote:
What I would do is
disable the servo (red swtich on th amplifier PCB
on top of the PSU), put
a folded imwipe between the heads and disable interlocks so the drive wil
lrun without a disk instaleld. Then move the carriage frowards by hand
wit hthe thing effectively spun up (the Kimwipe wil lavoid damaging the
heads) and look at the signals i nthe positioner servo circuit with a
'scope. Start wit hthe outputs of the transducer, see if all signals are
present and change as you move the carriage.
I do it the same way - but with a spinning disk in the drive. It comes out
the same...
Ph
12:30 p.m.
On 02/27/2014 11:25 AM, Marc Howard wrote:
Last night I cleaned the hell out of both the heads
and the disk pack. I
even tried Brakekleen on the leading surface of the bottom head but it
didn't remove anything. I had the best results with putting lint free
cloth soaked in 99.9% isopropyl alcohol between the loaded heads. Got the
top head clean except for a wide line somewhat less than 0.1" wide that
goes from top to bottom. It's so perfect it looks like the head was
somehow made that way. Bottom head only had a few small blemishes left.
Well, good for you! I went rummaging around a bit in my hellbox looking
for several rolls of 3M diamond lapping tape that I picked up years ago,
but no luck. The stuff is great--you can use the half-micron stuff on a
scratched-up head and it would come out looking like new.
--Chuck
1:26 p.m.
That's a great tip; I've never heard of that stuff before. I'm going to
have to buy some. Just briefly, how do you burnish the heads with it? Do
you wrap it around a tongue depressor or something else?
Thanks,
Marc
On Thu, Feb 27, 2014 at 12:30 PM, Chuck Guzis <cclist at sydex.com> wrote:
On 02/27/2014 11:25 AM, Marc Howard wrote:
Last night I cleaned the hell out of both the heads and the disk pack. I
even tried Brakekleen on the leading surface of
the bottom head but it
didn't remove anything. I had the best results with putting lint free
cloth soaked in 99.9% isopropyl alcohol between the loaded heads. Got the
top head clean except for a wide line somewhat less than 0.1" wide that
goes from top to bottom. It's so perfect it looks like the head was
somehow made that way. Bottom head only had a few small blemishes left.
Well, good for you! I went rummaging around a bit in my hellbox looking
for several rolls of 3M diamond lapping tape that I picked up years ago,
but no luck. The stuff is great--you can use the half-micron stuff on a
scratched-up head and it would come out looking like new.
--Chuck
3:05 p.m.
On 02/27/2014 01:26 PM, Marc Howard wrote:
That's a great tip; I've never heard of that
stuff before. I'm going to
have to buy some. Just briefly, how do you burnish the heads with it? Do
you wrap it around a tongue depressor or something else?
It may not be entirely correct, but the best do-it-yourself guide I've
ever run into was an old NOrtronics one:
http://www.recordist.com/ampex/docs/repairtips/heads/nortronics.pdf
Maybe that will help a bit. The audio tape forums typically also have
their own guides, as re-lapping audio tape heads is pretty common there.
I wonder if the same applies to old videotape equipment as well.
--Chuck
1 Mar
1 Mar
1:05 p.m.
That's a great tip; I've never heard of that stuff before. I'm going to
have to buy some. Just briefly, how do you burnish the heads with it? Do
you wrap it around a tongue depressor or something else?
I was going t oask much the same thing. Firstly, I asusem the Al_2O_3
lapping film is useless for doing harddisk haeds.
Seocndly, am I correct that the head should ahve a totally flat face. If
so, I ewould think about putting the lapping film on a piece of flat
glass or similar, adn polishing the head with it.
Thirdly, has anyone done this?
-tony
27 Feb
27 Feb
1:47 p.m.
On Feb 27, 2014, at 3:30 PM, Chuck Guzis <cclist at sydex.com> wrote:
On 02/27/2014 11:25 AM, Marc Howard wrote:
Wow, that stuff is expensive.
I mean... diamonds. But still. I suppose if I needed it, it would be
worth $300 a roll, but I don't need it that badly.
- Dave
Last night I cleaned the hell out of both the
heads and the disk pack. I
even tried Brakekleen on the leading surface of the bottom head but it
didn't remove anything. I had the best results with putting lint free
cloth soaked in 99.9% isopropyl alcohol between the loaded heads. Got the
top head clean except for a wide line somewhat less than 0.1" wide that
goes from top to bottom. It's so perfect it looks like the head was
somehow made that way. Bottom head only had a few small blemishes left.
Well, good for you! I went rummaging around a bit in my hellbox looking for several
rolls of 3M diamond lapping tape that I picked up years ago, but no luck. The stuff is
great--you can use the half-micron stuff on a scratched-up head and it would come out
looking like new.
2:22 p.m.
On Thu, Feb 27, 2014 at 1:47 PM, David Riley <fraveydank at gmail.com> wrote:
On Feb 27, 2014, at 3:30 PM, Chuck Guzis <cclist at
sydex.com> wrote:
Actually if you look around I found that there are companies that sell the
stuff in smaller quantities. Also cheaper on eBay.
Marc
Well, good for you! I went rummaging around a bit in my hellbox looking
for
several rolls of 3M diamond lapping tape that I picked up years ago,
but no luck. The stuff is great--you can use the half-micron stuff on a
scratched-up head and it would come out looking like new.
Wow, that stuff is expensive.
I mean... diamonds. But still. I suppose if I needed it, it would be
worth $300 a roll, but I don't need it that badly.
- Dave
2:30 p.m.
On Feb 27, 2014, at 2:22 PM, Marc Howard <cramcram at gmail.com> wrote:
On Thu, Feb 27, 2014 at 1:47 PM, David Riley
<fraveydank at gmail.com> wrote:
It also comes in pads and sheets. I've seen 0.5 micron stuff in packs < $30.
TTFN - Guy
On Feb 27, 2014, at 3:30 PM, Chuck Guzis
<cclist at sydex.com> wrote:
Actually if you look around I found that there are companies that sell the
stuff in smaller quantities. Also cheaper on eBay.
Well, good for you! I went rummaging around a bit in my hellbox looking
for
several rolls of 3M diamond lapping tape that I picked up years ago,
but no luck. The stuff is great--you can use the half-micron stuff on a
scratched-up head and it would come out looking like new.
Wow, that stuff is expensive.
I mean... diamonds. But still. I suppose if I needed it, it would be
worth $300 a roll, but I don't need it that badly.
- Dave
4:36 p.m.
On 27/02/2014 21:47, David Riley wrote:
On Feb 27, 2014, at 3:30 PM, Chuck Guzis <cclist at
sydex.com> wrote:
> Well, good for you! I went rummaging around a bit
in my hellbox
> looking for several rolls of 3M diamond lapping tape that I picked
> up years ago, but no luck. The stuff is great--you can use the
> half-micron stuff on a scratched-up head and it would come out
> looking like new.
I mean... diamonds. But still. I suppose if I needed
it, it would
be worth $300 a roll, but I don't need it that badly.
You can buy small sheets of diamond lapping film fairly inexpensively.
Various grades are used to polish the ends of fibre optic connectors
after the glass fibre is terminated in them.
--
Pete Peter Turnbull
Network Manager
University of York
1:13 p.m.
What I would do is
disable the servo (red swtich on th amplifier PCB on top of the PSU), put
a folded imwipe between the heads and disable interlocks so the drive wil
lrun without a disk instaleld. Then move the carriage frowards by hand
wit hthe thing effectively spun up (the Kimwipe wil lavoid damaging the
heads) and look at the signals i nthe positioner servo circuit with a
'scope. Start wit hthe outputs of the transducer, see if all signals are
present and change as you move the carriage.
I do it the same way - but with a spinning disk in the drive. It comes
out the same... 
26 Feb
26 Feb
8:09 p.m.
Most of the RK05 problems I've seen can be found by doing the semi- annual
or annual PM without the head alignment.
I always recommend this after long storage or shipping.
On Wed, Feb 26, 2014 at 12:06 AM, Marc Howard <cramcram at gmail.com> wrote:
I recently acquired 3 RK05j's that seem to have
spent time in a barn as
well as having been used by a heavy smoker. I thoroughly cleaned and
de-gray-foamed them as well as putting in new absolute filters.
The first one came up after cleaning with no issues. Works great.
Number two spins up but the initial seek emits a sickening "klang" as the
voice coil drives hard to the limit (yes, the graticule lamp is working).
Any ideas?
The third drive initially had really ugly heads that never cleaned up to my
liking. I loaded a disk anyway and for about 5 seconds after the initial
head load all was okay. Then I heard the sound of the top head scouring
the disk.
So I'm thinking of buying replacement heads off of eBay. Apparently these
are the heads but not the steel tongues that they mount on.
So I have some questions for anyone on the list who may have changed their
heads.
1. How hard is it to mount the head in the tongue? Looks like just 2
screws.
2. How hard is it to remove/replace the tongue assembly? Looks like it
mounts with a couple of allen screws.
3. How hard is it to align the heads? I don't have a CE pack so I'll just
have to use a pack that works okay on the other drive.
4. Any sage advice or whatever?
Thanks for any and all help.
Marc
3596
days inactive
3716
days old
29 comments
16 participants
participants (16)
-
ard＠p850ug1.demon.co.uk -
bigral＠hotmail.com -
cc＠informatik.uni-stuttgart.de -
cclist＠sydex.com -
cisin＠xenosoft.com -
cramcram＠gmail.com -
earl＠retrobits.com -
fraveydank＠gmail.com -
ggs＠shiresoft.com -
hachti＠hachti.de -
jws＠jwsss.com -
lbickley＠bickleywest.com -
mouse＠Rodents-Montreal.ORG -
paulkoning＠comcast.net -
pete＠dunnington.plus.com -
useddec＠gmail.com