Re: Bad heads on RL02: Worth replacing

2019-12-18 Thread Chris Zach via cctalk
Pulled the air filter on this unit. Completely plugged with brown/black 
junk, I can't believe much air was going through. So it's possible that 
the heads were in a partial vacuum and couldn't fly?


Off to find a fresh RL02 filter from Amazon. :-)

C

On 12/18/2019 9:37 AM, Chris Zach via cctalk wrote:
I don't believe there should be any contact to make any "wear" affect 
the head.  It may have been damaged if you're talking one of the heads 
you cleaned up.  But heads should never really contact the drive on 
these types of heads.


Thanks Jim: The problem was happening before I removed the head, and the 
symptoms (ring of white dust on the disk) has been going on for awhile 
so I don't think it was the cleaning that threw it out of alignment.


I took a set of watch calipers to the head this morning to see if I 
could measure the head width front to back (where front is the part of 
the head closest to the spindle and back is the part of the head 
furthest). Without removing the head from the head arm it's tricky to 
measure, but it's pretty clear that the ceramic on the rear of the head 
is thicker than the ceramic on the front of the head.


Which would make sense if it was dragging, as the ceramic would be worn 
down by the pressure of the arm spring pushing down more on the front 
than back. Once the head is angled it probably will not fly.


The next question and the really fun one is if the magnetic bar and 
loops that are embedded in the ceramic are above the level of the 
ceramic head. Ceramic on disk would leave wear, but I'll bet that steel 
of the magnet would carve a nice trench.


I'll try to take a picture this evening but in the meantime unless 
someone says that a wedge shaped head is "normal" I'm flagging this one 
as bad.


Thank you for the write-up below. Amazing stuff...

C



I haven't posted earlier, but I had the same head technology on 
Microdata and Western Dynex drives.  Those had spring steel welded 
from the frame that attaches the positioner and the wires run out to 
the head via that arm.


The thing I had happen was that in fiddling with the head, and 
cleaning it, one could flex the head mounting.  It was a very stiff 
probably stainless steel, but I suspect in cleaning efforts early on 
when I was working with the heads and drives I got hold of some which 
either I or someone prior had over flexed.  The clearance is so small 
that I think that tweek allows the head to look okay, but in actuality 
isn't flown in the proper orientation to stay clear of the media.


I built a number of drives up from highly abused parts, and there were 
a lot of them, so got to play back then and learn.  Huge numbers of 
media, junk drives and the like.


Once I got new heads the problems vanished.  Never did get a reliable 
way to ID a head as good, so I always had a non essential removable 
platter I'd fit the heads to and fly them to see if they caused 
damage. If not, I'd move them to the fixed disk on the bottom of the 
positioner, and mount two more on the top that I'd vetted.  That saved 
the most media and heads.


But unfortunately not good now days where media and heads are scarce, 
since it risks the media and heads.


thanks
Jim


Re: Bad heads on RL02: Worth replacing

2019-12-17 Thread jim stephens via cctalk




On 12/17/2019 8:05 PM, Chris Zach via cctalk wrote:
Took a look at the top of the RL02 pack. There is a fine layer of 
white stuff on the disk in a ring at about where I would assume track 
0 is on the thing. Wipes off with my finger, but definitely was not 
there when I put the pack in the drive.


Also, looking at the head under a loupe I can see the head is not 
perfectly flat when viewed from the side. The front (ahead of the air 
gap/groove) with the magnetic head is narrower than the back of it. 
I'm wondering if the head is *worn* to the point where it can't fly, 
contacts the pack, and what I am seeing on the pack is the ceramic 
from the head (which would be nice, meaning it's not ripping the pack 
apart). Then again the black stuff on the head is probably the top 
layer of oxide from the pack.


Do heads wear out?

C
I don't believe there should be any contact to make any "wear" affect 
the head.  It may have been damaged if you're talking one of the heads 
you cleaned up.  But heads should never really contact the drive on 
these types of heads.


I haven't posted earlier, but I had the same head technology on 
Microdata and Western Dynex drives.  Those had spring steel welded from 
the frame that attaches the positioner and the wires run out to the head 
via that arm.


The thing I had happen was that in fiddling with the head, and cleaning 
it, one could flex the head mounting.  It was a very stiff probably 
stainless steel, but I suspect in cleaning efforts early on when I was 
working with the heads and drives I got hold of some which either I or 
someone prior had over flexed.  The clearance is so small that I think 
that tweek allows the head to look okay, but in actuality isn't flown in 
the proper orientation to stay clear of the media.


I built a number of drives up from highly abused parts, and there were a 
lot of them, so got to play back then and learn.  Huge numbers of media, 
junk drives and the like.


Once I got new heads the problems vanished.  Never did get a reliable 
way to ID a head as good, so I always had a non essential removable 
platter I'd fit the heads to and fly them to see if they caused damage.  
If not, I'd move them to the fixed disk on the bottom of the positioner, 
and mount two more on the top that I'd vetted.  That saved the most 
media and heads.


But unfortunately not good now days where media and heads are scarce, 
since it risks the media and heads.


thanks
Jim


Re: Bad heads on RL02: Worth replacing

2019-12-17 Thread Chris Zach via cctalk
Took a look at the top of the RL02 pack. There is a fine layer of white 
stuff on the disk in a ring at about where I would assume track 0 is on 
the thing. Wipes off with my finger, but definitely was not there when I 
put the pack in the drive.


Also, looking at the head under a loupe I can see the head is not 
perfectly flat when viewed from the side. The front (ahead of the air 
gap/groove) with the magnetic head is narrower than the back of it. I'm 
wondering if the head is *worn* to the point where it can't fly, 
contacts the pack, and what I am seeing on the pack is the ceramic from 
the head (which would be nice, meaning it's not ripping the pack apart). 
Then again the black stuff on the head is probably the top layer of 
oxide from the pack.


Do heads wear out?

C


Re: Bad heads on RL02: Worth replacing

2019-12-17 Thread Al Kossow via cctalk



On 12/16/19 7:57 PM, Chris Zach via cctalk wrote:

> I'm wondering if the problem is the leading edge of the head is angled down 
> or something: From the debris on the leading
> edge it's looking like it is digging into the pack. Not sure if this can be 
> adjusted, or even what adjusting the head
> would be like.
> 

The characteristics of the head are not adjustable.
In my experience with 2315 packs, the top heads are the most prone to crashing.
You have to make sure the platter is absolutely clean, spinning at the right 
speed, and there is nothing on
the outer edge when the heads load.





Re: Bad heads on RL02: Worth replacing

2019-12-16 Thread Chris Zach via cctalk
On a funny side note, I have a -30 rating on Imgur now since a few of 
the posts of these drive heads were posted with names like "dirty 
bottom" and "clean top".


Ooops. Looks like drive heads are not a proper kink...

On 12/16/2019 10:57 PM, Chris Zach via cctalk wrote:
Well, I did check the head pretty thoroughly before installing it: One 
problem was there were dirt particles that were not coming off so I used 
the tip of a tweezer to loosen them up. Note I do this to watch dial 
faces from the 1870's (oddly enough also porcelain) so I'm pretty 
careful and am not making major scratches into that ceramic head.


But I did a finger check, it's smooth.

I'm wondering if the problem is the leading edge of the head is angled 
down or something: From the debris on the leading edge it's looking like 
it is digging into the pack. Not sure if this can be adjusted, or even 
what adjusting the head would be like.


Interesting. I'll check the pack next weekend for damage before trying 
it in the good RL02 to see if it has any more errors on the disk.


C


On 12/16/2019 7:23 PM, dwight via cctalk wrote:
The head likely has something on it that you missed. Use your finger 
to feel the head. Your finger is quite sensitive to tiny roughness. Of 
course, clean your finger oil off before putting it back in. Make sure 
that first landing area is smooth and flat. Almost all of the head 
needs to have the cushion of air. With things stationary, look at how 
the head comes down on the surface. The larger part needs to be 
parallel to the surface. Most heads have a slight curve on the leading 
edge to help trap the air.

Dwight


From: cctalk  on behalf of Chris Zach 
via cctalk 

Sent: Monday, December 16, 2019 3:07 PM
To: CCTalk mailing list 
Subject: Bad heads on RL02: Worth replacing

So one of my RL02 drives (bought on Ebay years ago) is eating RL02
packs. Makes tings, then the disks have errors in my other RL02 drive.
Took a bit to figure out which drive was eating what, but I'm 100%
certain it's this newer drive.

So pulled the heads. The top one had significant gunk on it, the bottom
one a bit. Pics below.

Top: https://i.imgur.com/FELhF9X.jpg
Bottom: https://i.imgur.com/Tmsf5Nd.jpg

With alcohol and lintless swabs I managed to clean both of the heads up.

Top: https://i.imgur.com/gmACM4R.jpg
Bottom: https://i.imgur.com/SfZQV5F.jpg

Then put them back in the drive and mounted a scratch pack. With finger
on the load/run I let the drive spin up and when I heard tinging I
immediately spun down. Hopefully I didn't trash my scratch pack.

Top head has gunk, bottom one had a few flecks, but looks pretty ok.
Top: https://i.imgur.com/EAvgmuH.jpg
Bottom: (picture didn't upload)

Obviously the head is crashing, any idea why and if it's worth replacing
the head or should I put this drive out for parts? Yes I cleaned the
RL02 pack before putting it in.

Never dull.
CZ



Re: Bad heads on RL02: Worth replacing

2019-12-16 Thread Chris Zach via cctalk
Well, I did check the head pretty thoroughly before installing it: One 
problem was there were dirt particles that were not coming off so I used 
the tip of a tweezer to loosen them up. Note I do this to watch dial 
faces from the 1870's (oddly enough also porcelain) so I'm pretty 
careful and am not making major scratches into that ceramic head.


But I did a finger check, it's smooth.

I'm wondering if the problem is the leading edge of the head is angled 
down or something: From the debris on the leading edge it's looking like 
it is digging into the pack. Not sure if this can be adjusted, or even 
what adjusting the head would be like.


Interesting. I'll check the pack next weekend for damage before trying 
it in the good RL02 to see if it has any more errors on the disk.


C


On 12/16/2019 7:23 PM, dwight via cctalk wrote:

The head likely has something on it that you missed. Use your finger to feel 
the head. Your finger is quite sensitive to tiny roughness. Of course, clean 
your finger oil off before putting it back in. Make sure that first landing 
area is smooth and flat. Almost all of the head needs to have the cushion of 
air. With things stationary, look at how the head comes down on the surface. 
The larger part needs to be parallel to the surface. Most heads have a slight 
curve on the leading edge to help trap the air.
Dwight


From: cctalk  on behalf of Chris Zach via cctalk 

Sent: Monday, December 16, 2019 3:07 PM
To: CCTalk mailing list 
Subject: Bad heads on RL02: Worth replacing

So one of my RL02 drives (bought on Ebay years ago) is eating RL02
packs. Makes tings, then the disks have errors in my other RL02 drive.
Took a bit to figure out which drive was eating what, but I'm 100%
certain it's this newer drive.

So pulled the heads. The top one had significant gunk on it, the bottom
one a bit. Pics below.

Top: https://i.imgur.com/FELhF9X.jpg
Bottom: https://i.imgur.com/Tmsf5Nd.jpg

With alcohol and lintless swabs I managed to clean both of the heads up.

Top: https://i.imgur.com/gmACM4R.jpg
Bottom: https://i.imgur.com/SfZQV5F.jpg

Then put them back in the drive and mounted a scratch pack. With finger
on the load/run I let the drive spin up and when I heard tinging I
immediately spun down. Hopefully I didn't trash my scratch pack.

Top head has gunk, bottom one had a few flecks, but looks pretty ok.
Top: https://i.imgur.com/EAvgmuH.jpg
Bottom: (picture didn't upload)

Obviously the head is crashing, any idea why and if it's worth replacing
the head or should I put this drive out for parts? Yes I cleaned the
RL02 pack before putting it in.

Never dull.
CZ



Re: Bad heads on RL02: Worth replacing

2019-12-16 Thread dwight via cctalk
The head likely has something on it that you missed. Use your finger to feel 
the head. Your finger is quite sensitive to tiny roughness. Of course, clean 
your finger oil off before putting it back in. Make sure that first landing 
area is smooth and flat. Almost all of the head needs to have the cushion of 
air. With things stationary, look at how the head comes down on the surface. 
The larger part needs to be parallel to the surface. Most heads have a slight 
curve on the leading edge to help trap the air.
Dwight


From: cctalk  on behalf of Chris Zach via cctalk 

Sent: Monday, December 16, 2019 3:07 PM
To: CCTalk mailing list 
Subject: Bad heads on RL02: Worth replacing

So one of my RL02 drives (bought on Ebay years ago) is eating RL02
packs. Makes tings, then the disks have errors in my other RL02 drive.
Took a bit to figure out which drive was eating what, but I'm 100%
certain it's this newer drive.

So pulled the heads. The top one had significant gunk on it, the bottom
one a bit. Pics below.

Top: https://i.imgur.com/FELhF9X.jpg
Bottom: https://i.imgur.com/Tmsf5Nd.jpg

With alcohol and lintless swabs I managed to clean both of the heads up.

Top: https://i.imgur.com/gmACM4R.jpg
Bottom: https://i.imgur.com/SfZQV5F.jpg

Then put them back in the drive and mounted a scratch pack. With finger
on the load/run I let the drive spin up and when I heard tinging I
immediately spun down. Hopefully I didn't trash my scratch pack.

Top head has gunk, bottom one had a few flecks, but looks pretty ok.
Top: https://i.imgur.com/EAvgmuH.jpg
Bottom: (picture didn't upload)

Obviously the head is crashing, any idea why and if it's worth replacing
the head or should I put this drive out for parts? Yes I cleaned the
RL02 pack before putting it in.

Never dull.
CZ


Re: Bad heads on RL02: Worth replacing

2019-12-16 Thread Guy Sotomayor Jr via cctalk



> On Dec 16, 2019, at 3:07 PM, Chris Zach via cctalk  
> wrote:
> 
> So one of my RL02 drives (bought on Ebay years ago) is eating RL02 packs. 
> Makes tings, then the disks have errors in my other RL02 drive. Took a bit to 
> figure out which drive was eating what, but I'm 100% certain it's this newer 
> drive.
> 
> So pulled the heads. The top one had significant gunk on it, the bottom one a 
> bit. Pics below.
> 
> Top: https://i.imgur.com/FELhF9X.jpg
> Bottom: https://i.imgur.com/Tmsf5Nd.jpg
> 
> With alcohol and lintless swabs I managed to clean both of the heads up.
> 
> Top: https://i.imgur.com/gmACM4R.jpg
> Bottom: https://i.imgur.com/SfZQV5F.jpg
> 
> Then put them back in the drive and mounted a scratch pack. With finger on 
> the load/run I let the drive spin up and when I heard tinging I immediately 
> spun down. Hopefully I didn't trash my scratch pack.
> 
> Top head has gunk, bottom one had a few flecks, but looks pretty ok.
> Top: https://i.imgur.com/EAvgmuH.jpg
> Bottom: (picture didn't upload)
> 
> Obviously the head is crashing, any idea why and if it's worth replacing the 
> head or should I put this drive out for parts? Yes I cleaned the RL02 pack 
> before putting it in.
> 
> Never dull.

I would try replacing the head(s).

TTFN - Guy



Bad heads on RL02: Worth replacing

2019-12-16 Thread Chris Zach via cctalk
So one of my RL02 drives (bought on Ebay years ago) is eating RL02 
packs. Makes tings, then the disks have errors in my other RL02 drive. 
Took a bit to figure out which drive was eating what, but I'm 100% 
certain it's this newer drive.


So pulled the heads. The top one had significant gunk on it, the bottom 
one a bit. Pics below.


Top: https://i.imgur.com/FELhF9X.jpg
Bottom: https://i.imgur.com/Tmsf5Nd.jpg

With alcohol and lintless swabs I managed to clean both of the heads up.

Top: https://i.imgur.com/gmACM4R.jpg
Bottom: https://i.imgur.com/SfZQV5F.jpg

Then put them back in the drive and mounted a scratch pack. With finger 
on the load/run I let the drive spin up and when I heard tinging I 
immediately spun down. Hopefully I didn't trash my scratch pack.


Top head has gunk, bottom one had a few flecks, but looks pretty ok.
Top: https://i.imgur.com/EAvgmuH.jpg
Bottom: (picture didn't upload)

Obviously the head is crashing, any idea why and if it's worth replacing 
the head or should I put this drive out for parts? Yes I cleaned the 
RL02 pack before putting it in.


Never dull.
CZ