3 Aug
2014
3 Aug
'14
12:46 a.m.
I have a Tandon TM-848E 8" floppy drive which appears to have become a disk lathe. Or
perhaps just an effective disk eraser. It's one half of an external dual 8" drive
unit that I picked up off eBay several months ago. I've cleaned the heads, and I
can't see any sharp spots or debris with my head-mounted magnifying lenses, but it
continues to scrape rings in the oxide of a disk on both sides. I haven't tried
removing the heads to put them under my microscope since that would destroy the
alignment.
I've only tested it with the pair of disks that came in the drive so far. It's
possible that they are bad disks with soft oxide, but I haven't seen the same scraping
problem so far in the other drive of the pair. So, that one drive appears to be a disk
lathe now. I haven't felt up to risking a potentially good disk in the bad one.
Have any of y'all seen this kind of problem before? Is it likely to be repairable,
even if that involves removing the heads and then realigning the drive when I reinstall
them? Or is it most likely that the drive is fine and I've just been putting bad disks
in it? I don't have any alignment diskettes yet, but I may get some one of these
days.
For the time being, I'm assuming that I'll just use the drive as a source of parts
for other TM-848-series drives in my collection, like one that I have with a broken latch
handle. The other drive plus the enclosure is earmarked for use with my KryoFlux.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
3 Aug
3 Aug
1:31 a.m.
Ok, I may have been too quick to jump to conclusions. While playing with the other
"good" drive on a floppy disk exerciser, it also started making the
fingernails-on-chalkboard sound. I can scrape the oxide of the disk that was in it with a
fingernail near the hub of the disk, so I think these are just bad disks.
I have many various old 8" floppies that I've been hoping to try to image. If I
can scrape the oxide with a fingernail, is it worth trying to read the disk, or will it
just crud up the heads of whatever drive I put it in?
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
1:50 a.m.
On Sat, 2 Aug 2014, Mark J. Blair wrote:
Ok, I may have been too quick to jump to conclusions.
While playing with
the other "good" drive on a floppy disk exerciser, it also started
making the fingernails-on-chalkboard sound. I can scrape the oxide of
the disk that was in it with a fingernail near the hub of the disk, so I
think these are just bad disks.
I have many various old 8" floppies that I've been hoping to try to
image. If I can scrape the oxide with a fingernail, is it worth trying
to read the disk, or will it just crud up the heads of whatever drive I
put it in?
I wonder if it's useful to polish read-write heads.
--
David Griffith
dgriffi at cs.csubak.edu
1:49 a.m.
On 08/02/2014 09:46 PM, Mark J. Blair wrote:
Have any of y'all seen this kind of problem
before? Is it likely to
be repairable, even if that involves removing the heads and then
realigning the drive when I reinstall them? Or is it most likely that
the drive is fine and I've just been putting bad disks in it? I don't
have any alignment diskettes yet, but I may get some one of these
days.
I see this more than I'd care to. A lot of disks that are only 20 years
old are developing binder failures. This is first cousin to the
infamous "sticky shed" problem talked about in the audio tape forums.
Some brands are worse than others.
The solution is the same for old disks--bake them at about 140F/58C for
several hours. The same goes for flaky tapes.
Clean your drive heads, and try some known-good media.
--Chuck
2:34 a.m.
On Aug 2, 2014, at 22:49 , Chuck Guzis <cclist at sydex.com> wrote:
The solution is the same for old disks--bake them at
about 140F/58C for several hours. The same goes for flaky tapes.
I'll need to figure out a good way to do that. My kitchen oven only goes down to
170F.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
3 a.m.
On 8/3/2014 12:34 AM, Mark J. Blair wrote:
On Aug 2, 2014, at 22:49 , Chuck Guzis <cclist at sydex.com> wrote:
What about a food dehydrator?
I would have thought old disks would have been archived 20 years ago?
What was on them?
Ben.
The solution is the same for old disks--bake them
at about 140F/58C for several hours. The same goes for flaky tapes.
I'll need to figure out a good way to do that. My kitchen oven only goes down to
170F.
3:12 a.m.
On Aug 3, 2014, at 00:00 , ben <bfranchuk at jetnet.ab.ca> wrote:
What about a food dehydrator?
Good idea... I'll look those up. I had been looking at lab ovens, environmental
chambers and incubators, but not finding something both "right" and
"cheap".
I would have thought old disks would have been
archived 20 years ago? What was on them?
Among other things, XENIX for my Tandy 6000. Much stuff has been archived, but there are
also vast gaps in the record; at least in the stuff I've managed to google up, that
is.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
11:14 a.m.
On 08/03/2014 12:12 AM, Mark J. Blair wrote:
On Aug 3, 2014, at 00:00 , ben <bfranchuk at jetnet.ab.ca> wrote:
A food dehydrator might work--just make sure that the thermostat doesn't
have too wide a deadband--you don't want to melt the things. I did some
experiments some time back and found that a temperature of 53C had
little effect, but 58C did the trick, so the temp is somewhat critical.
An incubator might also do the trick. My own setup is a nice piece of
furniture, and uses a PID controller but I suspect that there are all
sorts of setups that should work. Do not use your kitchen oven--the low
temperature control on those is terrible. My own "cooker" will hold to
+/- 0.5C.
--Chuck
What about a food dehydrator?
Good idea... I'll look those up. I had been looking at lab ovens,
environmental chambers and incubators, but not finding something both
"right" and "cheap". 
11:33 a.m.
On 8/3/14 8:14 AM, Chuck Guzis wrote:
A food dehydrator might work--just make sure that the
thermostat doesn't have too wide a deadband--you don't want to melt the things. I
did some experiments some time back and found that a
temperature of 53C had little effect, but 58C did the trick, so the temp is somewhat
critical.
At least with tape, air flow is critical. You have to push a lot of air into the reel to
get at the inner wraps.
I've never tried baking floppies in the oven I built because of the air flow (9
5" muffin fans in the bottom between
the heating element and the tape) so if this works out I may get one just for dealing with
floppies.
You might also look for a Shugart 850 in good shape instead of the Tandon. I don't
really like Tandons very much.
Important thing to consider is easy access to the heads. Qume drives are difficult to get
to the heads. I've also
had better luck with a single sided drive as far as head damage to media if what you need
to read is only single-sided.
12:09 p.m.
On 08/03/2014 08:33 AM, Al Kossow wrote:
At least with tape, air flow is critical. You have to
push a lot of air
into the reel to get at the inner wraps.
I've never tried baking floppies in the oven I built because of the air
flow (9 5" muffin fans in the bottom between
the heating element and the tape) so if this works out I may get one
just for dealing with floppies.
I went to a traditional induction motor fan running at low speed (lots
of volume, not much velocity). I bake tapes for most of a day, then
allow them to cool overnight. So far, so good.
I don't much care for the 848s either. One aspect is that the drive
spindle motor itself is 24V, but the positioner is 12V. There's a
somewhat over-taxed LM7812 to drop the voltage accordingly, which often
fails--that must have been known, because there's a fuse in series with it.
--Chuck
12:26 p.m.
On Aug 3, 2014, at 09:09 , Chuck Guzis <cclist at sydex.com> wrote:
I don't much care for the 848s either. One aspect
is that the drive spindle motor itself is 24V, but the positioner is 12V. There's a
somewhat over-taxed LM7812 to drop the voltage accordingly, which often fails--that must
have been known, because there's a fuse in series with it.
I had a TM-848 (an earlier belt-drive one) in my TRS-80 Model 12 that shorted the 24V
supply. That LM7812 was the first thing that I suspected, but the problem turned out to be
a shorted filter capacitor right before it.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
2:18 p.m.
On 08/03/2014 09:26 AM, Mark J. Blair wrote:
I had a TM-848 (an earlier belt-drive one) in my
TRS-80 Model 12 that
shorted the 24V supply. That LM7812 was the first thing that I
suspected, but the problem turned out to be a shorted filter
capacitor right before it.
Yup, I've seen that too. It's a lousy design.
--Chuck
2:43 p.m.
On Aug 3, 2014, at 11:18 , Chuck Guzis <cclist at sydex.com> wrote:
Yup, I've seen that too. It's a lousy design.
Judging by eBay prices, 8" drives and anything made by Shugart must be made of
gold-plated cocaine. The Tandon drives look like they ought to be good... after all,
they're nice, sexy half-height drives, and later ones have direct drive spindles. But
then you try to clean the heads or put out the regulator/capacitor fire, and your opinion
changes. :)
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
12:20 p.m.
On Aug 3, 2014, at 08:33 , Al Kossow <aek at bitsavers.org> wrote:
You might also look for a Shugart 850 in good shape
instead of the Tandon. I don't really like Tandons very much.
Important thing to consider is easy access to the heads. Qume drives are difficult to get
to the heads. I've also
had better luck with a single sided drive as far as head damage to media if what you need
to read is only single-sided.
That's a good point regarding head access. On the TM-848E, I need to remove one of the
PCBs to get access to the heads.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
12:48 p.m.
On Aug 3, 2014, at 08:14 , Chuck Guzis <cclist at sydex.com> wrote:
A food dehydrator might work--just make sure that the
thermostat doesn't have too wide a deadband--you don't want to melt the things. I
did some experiments some time back and found that a temperature of 53C had little effect,
but 58C did the trick, so the temp is somewhat critical.
If the mechanical stuff, heater and blower are sufficient in these units, then replacing
the thermostat with a better controller probably wouldn't be too difficult or
expensive.
My own setup is a nice piece of furniture, and uses a
PID controller but I suspect that there are all sorts of setups that should work.
That sounds like overkill. I LIKE overkill! :)
On Aug 3, 2014, at 08:33 , Al Kossow <aek at bitsavers.org> wrote:
At least with tape, air flow is critical. You have to
push a lot of air into the reel to get at the inner wraps.
For tapes, is it necessary to do more than simply setting the tape reel in the ez-bake
tape oven? I haven't encountered any 1/2" tapes that need baking yet, but I'm
sure it's only a matter of time.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
4:12 p.m.
> A food dehydrator might work--just make sure that
the thermostat
On Sun, 3 Aug 2014, Mark J. Blair wrote:
If the mechanical stuff, heater and blower are
sufficient in these
units, then replacing the thermostat with a better controller probably
wouldn't be too difficult or expensive.
If you can monitor and regulate the temperature, then all that is needed
is a box and a few hundred watts of incandescent light bulbs (or DOZENS of
CFLs)
4:31 p.m.
On Aug 3, 2014, at 13:12 , Fred Cisin <cisin at xenosoft.com> wrote:
If you can monitor and regulate the temperature, then
all that is needed
is a box and a few hundred watts of incandescent light bulbs (or DOZENS of
CFLs)
I'd add some fans to circulate the air, too, in order to avoid hot spots. I figure
that building a media oven from scratch vs. buying a dehydrator is a time vs. money
trade-off. With the right stuff in your junk pile, building one should be pretty easy.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
5:17 p.m.
On 08/03/2014 01:12 PM, Fred Cisin wrote:
If you can monitor and regulate the temperature, then
all that is needed
is a box and a few hundred watts of incandescent light bulbs (or DOZENS of
CFLs)
Nothing so extreme, if you're doing things right. Insulation is
everything--my box is insulated with 1" extruded polystyrene foam
against 3/4" plywood. It takes about 20 minutes to come up to working
temperature using nothing more than a 75W incandescent lamp.
--Chuck
3:34 a.m.
On Aug 3, 2014, at 00:00 , ben <bfranchuk at jetnet.ab.ca> wrote:
What about a food dehydrator?
Maybe something like this?
http://www.ebay.com/itm/331183542811
Also good for jerky, though it might not be advisable to cook meat and disks at the same
time. :)
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
11:16 a.m.
On 8/3/14 12:34 AM, Mark J. Blair wrote:
On Aug 3, 2014, at 00:00 , ben <bfranchuk at jetnet.ab.ca> wrote:
That looks like it could work quite well, though I would probably use two racks and figure
out
an arrangement to clip the edges of the media pancake and hold it vertically so it's
not sitting
on the rack.
What about a food dehydrator?
Maybe something like this?
http://www.ebay.com/itm/331183542811
3:04 p.m.
On Sun, 3 Aug 2014, Al Kossow wrote:
On 8/3/14 12:34 AM, Mark J. Blair wrote:
>
> On Aug 3, 2014, at 00:00 , ben <bfranchuk at jetnet.ab.ca> wrote:
>> What about a food dehydrator?
>
> Maybe something like this?
>
> http://www.ebay.com/itm/331183542811
>
Or, maybe this one at somewhat less expense? (No fan, however):
eBay: 191217447033
--
3:32 p.m.
On 08/03/2014 12:04 PM, Steven Hirsch wrote:
Or, maybe this one at somewhat less expense? (No fan,
however):
eBay: 191217447033
If that's your pleasure, fine. But personally, I'd check out the local
Goodwill or thrift store first. A zillion of these were sold, thanks to
TV informercial marketing.
--Chuck
9:14 p.m.
On Sun, 3 Aug 2014, Chuck Guzis wrote:
On 08/03/2014 12:04 PM, Steven Hirsch wrote:
That's a good idea - thanks. I got out of the habit of checking Salvation
Army and Goodwill stores when they began sending computer equipment
directly to the recylclers.
--
Or, maybe this one at somewhat less expense? (No
fan, however):
eBay: 191217447033
If that's your pleasure, fine. But personally, I'd check out the local
Goodwill or thrift store first. A zillion of these were sold, thanks to TV
informercial marketing. 
4 Aug
4 Aug
12:29 a.m.
Although, not the easiest thing to do, there is a way to
read the disk without causing the damage that heads can do.
The bit are possible to be read optically. One uses a material
like used for magnaflux.
Dwight
1:01 a.m.
On Sun, 3 Aug 2014, dwight wrote:
Although, not the easiest thing to do, there is a way
to
read the disk without causing the damage that heads can do.
The bit are possible to be read optically. One uses a material
like used for magnaflux.
Aside from the THEORETICAL, what is your current mean number
of bits between errors?
Aside from the THEORETICAL, how long does it currently take
to read a 360K floppy?
1:24 a.m.
On Sun, Aug 3, 2014 at 10:29 PM, dwight <dkelvey at hotmail.com> wrote:
Although, not the easiest thing to do, there is a way
to
read the disk without causing the damage that heads can do.
The bit are possible to be read optically. One uses a material
like used for magnaflux.
Is there any way to use the Faraday effect to read a magnetic disk optically?
1:58 a.m.
On 08/03/2014 10:24 PM, Eric Smith wrote:
On Sun, Aug 3, 2014 at 10:29 PM, dwight <dkelvey at
hotmail.com> wrote:
Assuming that you could keep the correct clearance, I imagine that a
moder GMR head might do the trick. The gotcha, of course, is
"maintaining correct clearance".
I'd heard about 3M using a colloidal iron suspension (e.g. visamag,
magnasee, kyread) and scanning the disk surface with a laser.
I imagine that a setup using a CD read head might do the trick, but I
doubt that the work that went into the setup would pay for itself.
--Chuck
Although, not the easiest thing to do, there is a
way to
read the disk without causing the damage that heads can do.
The bit are possible to be read optically. One uses a material
like used for magnaflux.
Is there any way to use the Faraday effect to read a magnetic disk optically?
9:22 a.m.
Date: Sun, 3 Aug 2014 23:24:39 -0600
Subject: Re: An 8 Inch Disk Lathe
From: spacewar at gmail.com
To: cctalk at classiccmp.org
On Sun, Aug 3, 2014 at 10:29 PM, dwight <dkelvey at hotmail.com> wrote:
The
3D glasses I last used at the theater was circularly polarized.There seem to be two types
of 3D, one uses linearly polarized and the otherused circularly polarized. One can tell
the difference by tilting their headthe linear ones will begin to leak through the other
image and the circularones are not effected.I wonder if it requires some special fluid or
just any fluid?In any case I think one could make the entire thing automatic.Read the disk
into a image and have image recognition extract the bits.As long as the entire track
wasn't destroyed by the head it might be possibleto recover from what remains of disk
that had been trimmed by a"8 inch disk lathe".A long time ago, I recall seeing
an article about reading the disk withsomething optical. It didn't go into detail but
showed a microscopepicture to the magnetic transitions on several tracks. One could
easilysee the transitions with the method they used.Dwight
Although, not the easiest thing to do, there is a
way to
read the disk without causing the damage that heads can do.
The bit are possible to be read optically. One uses a material
like used for magnaflux.
Is there any way to use the Faraday effect to read a magnetic disk optically? 
9 p.m.
On Sunday (08/03/2014 at 09:14PM -0400), Steven Hirsch wrote:
On Sun, 3 Aug 2014, Chuck Guzis wrote:
And then you can make that junked toaster oven or dehydrator, dead nuts
accurate for another $28,
http://www.ebay.com/itm/141021325676
AC 110-240V Digital PID Temperature controller + 25A SSR + K thermocouple
Sensor
--
Chris Elmquist
On 08/03/2014 12:04 PM, Steven Hirsch wrote:
That's a good idea - thanks. I got out of the habit of checking
Salvation Army and Goodwill stores when they began sending computer
equipment directly to the recylclers. Or, maybe this one at somewhat less expense? (No
fan, however):
eBay: 191217447033
If that's your pleasure, fine. But personally, I'd check out the
local Goodwill or thrift store first. A zillion of these were
sold, thanks to TV informercial marketing.
5 Aug
5 Aug
12:06 a.m.
On 08/04/2014 06:00 PM, Chris Elmquist wrote:
http://www.ebay.com/itm/141021325676
AC 110-240V Digital PID Temperature controller + 25A SSR + K thermocouple
Sensor
That particular model has a very bad reputation among the homebrew (in
the original sense--the beermakers). The Sestors and Mypin units are
somewhat better for very little more.
--Chuck
12:35 a.m.
On 8/4/2014 10:06 PM, Chuck Guzis wrote:
On 08/04/2014 06:00 PM, Chris Elmquist wrote:
I could be wrong, but do you not want beer cool rather than hot?
http://www.ebay.com/itm/141021325676
AC 110-240V Digital PID Temperature controller + 25A SSR + K thermocouple
Sensor
That particular model has a very bad reputation among the homebrew (in
the original sense--the beermakers). The Sestors and Mypin units are
somewhat better for very little more. --Chuck
Ben.
1:21 a.m.
On 08/04/2014 09:35 PM, ben wrote:
I could be wrong, but do you not want beer cool rather than hot?
If you're drinking it, sure, but not if you're brewing it. Hey, those
guys are serious... There's a TV program broadcast on some of the
local channels that is nothing more than beer tasting. The panel is
typically about 3 or 4 guys with serious adipose tissue.
--Chuck
1:40 a.m.
On 8/4/2014 11:21 PM, Chuck Guzis wrote:
On 08/04/2014 09:35 PM, ben wrote:
All I know with homemade root beer you need it cool, not cold!
There's a TV program broadcast on some of the
I could be wrong, but do you not want beer cool rather than hot?
If you're drinking it, sure, but not if you're brewing it. Hey, those
guys are serious... local channels that is nothing more than beer tasting.
The panel is
typically about 3 or 4 guys with serious adipose tissue.
They can taste -- real men DRINK.
--Chuck
Ben.
14 Aug
14 Aug
10:34 p.m.
On 8/3/14 8:16 AM, Al Kossow wrote:
On 8/3/14 12:34 AM, Mark J. Blair wrote:
Ordered one, and a mypin TA6 which arrived today.
Monitoring with the TA6 and not controlling the heater the
stock thermostat seems to be holding +/- .5 deg C at 58.
I sat 10 2400' MRX V (gag..) tapes on the racks that I wouldn't cry over if they
didn't work out.
We'll see how they do tomorrow.
On Aug 3, 2014, at 00:00 , ben <bfranchuk at jetnet.ab.ca> wrote:
That looks like it could work quite well, though I would probably use two racks and
figure out
an arrangement to clip the edges of the media pancake and hold it vertically so it's
not sitting
on the rack.
What about a food dehydrator?
Maybe something like this?
http://www.ebay.com/itm/331183542811
15 Aug
15 Aug
1:01 a.m.
AL, can I bring my next years apricots by to use your off time
of that machine?
Dwight
Date: Thu, 14 Aug 2014 19:34:47 -0700
From: aek at bitsavers.org
To: cctalk at classiccmp.org
Subject: Re: An 8 Inch Disk Lathe
On 8/3/14 8:16 AM, Al Kossow wrote:
On 8/3/14 12:34 AM, Mark J. Blair wrote:
Ordered one, and a mypin TA6 which arrived today.
Monitoring with the TA6 and not controlling the heater the
stock thermostat seems to be holding +/- .5 deg C at 58.
I sat 10 2400' MRX V (gag..) tapes on the racks that I wouldn't cry over if they
didn't work out.
We'll see how they do tomorrow.
On Aug 3, 2014, at 00:00 , ben <bfranchuk at jetnet.ab.ca> wrote:
That looks like it could work quite well, though I would probably use two racks and
figure out
an arrangement to clip the edges of the media pancake and hold it vertically so it's
not sitting
on the rack.
What about a food dehydrator?
Maybe something like this?
http://www.ebay.com/itm/331183542811
2:02 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 8/14/14 7:34 PM, Al Kossow wrote:
Ordered one, and a mypin TA6 which arrived today.
Monitoring with the TA6 and not controlling the heater the
stock thermostat seems to be holding +/- .5 deg C at 58.
I sat 10 2400' MRX V (gag..) tapes on the racks that I wouldn't cry over if they
didn't work out.
We'll see how they do tomorrow.
Looks like it worked fine. 10 tapes that didn't stick while retensioning. I was a
little concerned
since the airflow is a lot lower than my old oven (which was also a closed system with a
dehydrator)
but it seems to do the trick.
The front door of the oven has vents on it, and there was a film of white powdery
condensate there,
so it must have been pulling something volatile out of the binder.
I've just started a second batch, we'll see if it is repeatable. I'm curious
about the white film
if it actually came out of the tape or if it was just the oven outgassing something.
I bought the new one to try with 3M cartridges. I'll try those as the next batch.
2:34 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
so u wired a thermistate to your oven?
2:40 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On Aug 15, 2014, at 11:02 , Al Kossow <aek at bitsavers.org> wrote:
On 8/14/14 7:34 PM, Al Kossow wrote:
> Ordered one, and a mypin TA6 which arrived today.
Which dehydrator did you order?
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
4:45 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 8/15/14 11:40 AM, Mark J. Blair wrote:
On Aug 15, 2014, at 11:02 , Al Kossow <aek at bitsavers.org> wrote:
the one you pointed out
http://www.ebay.com/itm/331183542811
there are dozens of people selling them, so I went with the lowest price
On 8/14/14 7:34 PM, Al Kossow wrote:
> Ordered one, and a mypin TA6 which arrived today.
Which dehydrator did you order?
so u wired a thermistate to your oven?
It has one, which appears to be good to +/- .5 deg C
I've been using the Mypin just as a thermostat for the first two batches
5:31 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On Aug 15, 2014, at 13:45 , Al Kossow <aek at bitsavers.org> wrote:
On 8/15/14 11:40 AM, Mark J. Blair wrote:
Thank you. Are you satisfied with the quality of the mechanical stuff, heating elements
and blowers? I figure that the electronics are easily replaced or upgraded if inadequate.
Is this unit worth buying, vs. cramming some insulation, a lamp and a blower inside some
arbitrary box or cabinet?
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
Which dehydrator did you order?
the one you pointed out
http://www.ebay.com/itm/331183542811
6:38 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 8/15/14 2:31 PM, Mark J. Blair wrote:
Thank you. Are you satisfied with the quality of the
mechanical stuff, heating elements and blowers? I figure that the electronics are easily
replaced or upgraded if inadequate. Is this unit worth buying, vs. cramming some
insulation, a lamp and a blower inside some arbitrary box or cabinet?
It's Chinese sheet metal. There is a circular heating element behind the fan.
After all the metalwork that I had to do when I built the first one, it was
easier to just buy something and plug it in.
The reason I got it was for the wire racks. It is easy to set a bunch of 3M carts
on them with their plastic covers off. My other one has the fans and heater in the
bottom and a rod that the tape hubs went through so they just hung vertically in
the airflow. That obviously wouldn't work for carts and I couldn't think of an
easy
way off the top of my head to keep the tapes in the carts from unrolling. I think
the airflow is slow enough that I'm not going to have to do anything in the new one,
just unscrew and pop the plastic tops off the carts, take the tension belts off and
bake 'em as is.
I suspect the volume I need to bake is a bit higher than your needs as well. I'm
guessing I have a backlog of 500 carts I need to deal with.
7:29 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On Fri, 15 Aug 2014, Al Kossow wrote:
I suspect the volume I need to bake is a bit higher
than your needs as well. I'm
guessing I have a backlog of 500 carts I need to deal with.
THEN, you can start on Dwight's apricots and my plums!
7:39 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 08/15/2014 03:38 PM, Al Kossow wrote:
The reason I got it was for the wire racks. It is easy
to set a bunch of
3M carts
Heh, for 9 track tapes, I use inverted sour-cream containers. a tape
hub fits nicely over the tapered container and they stack nicely.
--Chuck
6:42 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 08/15/2014 02:31 PM, Mark J. Blair wrote:
On Aug 15, 2014, at 13:45 , Al Kossow <aek at bitsavers.org> wrote:
> the one you pointed out
> http://www.ebay.com/itm/331183542811
Over $200? Holy cow--my big expense was for the PID controller and some
73C thermal safety fuses. The rest I already had-3/4" oak-veneer
plywood, some 3/4" oak board, extruded 1" poly insulation, cabinet
hardware, fan, terminal strips, AC receptacles, fuse holders, casters,
etc. all were part of my hellbox contents. I even had the stain and
varnish on hand. Even the halogen lamp used to heat the thing is
probably over 20 years old.
--Chuck
8:03 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 8/15/14 3:42 PM, Chuck Guzis wrote:
Over $200? Holy cow--my big expense was for the PID
controller and some 73C thermal safety fuses.
Whatever.. CHM has no shop, no supplies, and a few tools that either I or the maint guys
have.
I also had to pay for it.
It was worth it to me to not have to build it. All I had to do was stuff the PID
controller thermocouple
inside the chamber so I could get an accurate temperature reading.
8:38 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On Aug 15, 2014, at 17:03 , Al Kossow <aek at bitsavers.org> wrote:
On 8/15/14 3:42 PM, Chuck Guzis wrote:
I see it as a time vs. money trade-off. The choice between spending the time to build it
or the money to buy it is a matter of personal preference and individual situation.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
Over $200? Holy cow--my big expense was for the
PID controller and some 73C thermal safety fuses.
Whatever.. CHM has no shop, no supplies, and a few tools that either I or the maint guys
have.
I also had to pay for it.
16 Aug
16 Aug
3:21 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 8/15/14 11:02 AM, Al Kossow wrote:
Looks like it worked fine. 10 tapes that didn't
stick while retensioning. I was a little concerned
since the airflow is a lot lower than my old oven (which was also a closed system with a
dehydrator)
but it seems to do the trick.
Well, there is a new winner in the "most evil tape category" that makes MRX V
look good in comparison.
Wabash (who would have guessed..)
Two passes through the new oven and they still shed like crazy.
Fortunately, I have a new method for retensioning so I never even get as far as seeing
a drive start shoeshining now. I found some lint-free wipes that are SUPER strong woven
fibre that I put over the blade of a portable tape cleaner and slowly work across the
surface as the tape retensions. Works like a charm (no more squeels on the drive) and
I know how bad the tape is up front by how much is on the wipe.
The Wabash is BAD
I set up the old oven to see if greatly increased airflow helps at all to recover these.
Figures these would be the four tapes that someone in Boston REALLY wants the bits from.
4:31 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 08/16/2014 12:21 PM, Al Kossow wrote:
Well, there is a new winner in the "most evil
tape category" that makes
MRX V look good in comparison.
Wabash (who would have guessed..)
Well, I've discovered that it appears to be "Wabash of a certain
vintage". I've got a reel of Wabash here with no fewer than 4 leaders
spliced on--this thing has been around the block a few times. From
1978. Reads like a dream.
80s Wabash is a nasty affair for me, no matter what the medium. The
awful thing is that they OEMed the stuff to a number of different sellers.
Memorex must have sold a ton of the MRX stuff in the day. I've seen
more of it than I care for.
I've been toying with a rig that will wipe a very thin layer of
cyclomethicone onto the most problematic of tapes in the hope that the
reduced friction will reduce shedding. No results yet.
--Chuck
4:40 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 8/16/14 1:31 PM, Chuck Guzis wrote:
80s Wabash is a nasty affair for me, no matter what
the medium. The awful thing is that they OEMed the stuff to a number of different
sellers.
Mid-80's Wabash. The bottom of the barrel.
Memorex must have sold a ton of the MRX stuff in the
day. I've seen more of it than I care for.
It was cheap. You also would get a couple bad reels right out of a new box.
17 Aug
17 Aug
12:43 p.m.
New subject: Tape Oven (was Re: An 8 Inch Disk Lathe)
On 08/16/2014 01:40 PM, Al Kossow wrote:
It was cheap. You also would get a couple bad reels right out of a new box.
The WikiP timeline for the 80s is kind of interesting;
Apr 1981 - Burroughs acquires Memorex
Apr 1982 - Burroughs sells Memorex consumer brand to Tandy
May 1985 - Burroughs exits OEM disk drive business, selling sales and
service to Toshiba
Sep 1986 - Burroughs acquires Sperry and renames itself as Unisys
Dec 1986 - Unisys spins off Memorex Media, Telecommunications and
International businesses as Memorex International NV.
Jan 1988 - Memorex-Telex merger[7]
Dec 1988 - Unisys mainly shuts down large disk business and spins off
service and repair as Sequel.
I had not realized that Tandy owned the Memorex consumer brand. I do
remember that Ella Fitzgerald commercials, but that was from the 1970s.
Audio cassettes were one of those lipstick-on-a-pig innovations.
--Chuck
13 Aug
13 Aug
2:26 p.m.
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On 08/02/2014 11:34 PM, Mark J. Blair wrote:
I'll need to figure out a good way to do that. My
kitchen oven only
goes down to 170F.
What about a toaster oven?
- --
The Doctor [412/724/301/703] [ZS]
Developer, Project Byzantium: http://project-byzantium.org/
PGP: 0x807B17C1 / 7960 1CDC 85C9 0B63 8D9F DD89 3BD8 FF2B 807B 17C1
WWW: https://drwho.virtadpt.net/
"There should always be a spectre at the feast." --Sherlock Holmes
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