Capstan slipping

[Carey Carlan]

Time for my world to grow a bit again.

The culprit: 3M 203 tape 1 mil, not back coated.
The problem: My recorder won't pull it at speed. I'm getting wild speed
errors as it slips in the capstan.

I've cleaned the capstan with everything from alcohol to Windex and it
still slips.

Suggestions?

This is the trophy tape of my collection--a 1969 recital to be presented at
a 2006 performance by the same artist.

[Steve Urbach]

On Fri, 25 Aug 2006 02:00:43 GMT, Carey Carlan >
wrote:

>Time for my world to grow a bit again.
>
>The culprit: 3M 203 tape 1 mil, not back coated.
>The problem: My recorder won't pull it at speed. I'm getting wild speed
>errors as it slips in the capstan.
>
>I've cleaned the capstan with everything from alcohol to Windex and it
>still slips.
>
>Suggestions?
>
>This is the trophy tape of my collection--a 1969 recital to be presented at
>a 2006 performance by the same artist.
Sounds like a shiny / hard pinch roller or insufficient pinch roller
pressure.

[Laurence Payne]

On Fri, 25 Aug 2006 02:00:43 GMT, Carey Carlan >
wrote:

>Time for my world to grow a bit again.
>
>The culprit: 3M 203 tape 1 mil, not back coated.
>The problem: My recorder won't pull it at speed. I'm getting wild speed
>errors as it slips in the capstan.
>
>I've cleaned the capstan with everything from alcohol to Windex and it
>still slips.
>
>Suggestions?
>
>This is the trophy tape of my collection--a 1969 recital to be presented at
>a 2006 performance by the same artist.

Will other tapes play OK on that machine?

As this is such an important recording, presumably you long ago made
copies onto other media? How important is it that the tape copy
survives?

[Mike Rivers]

Carey Carlan wrote:

> The culprit: 3M 203 tape 1 mil, not back coated.
> The problem: My recorder won't pull it at speed. I'm getting wild speed
> errors as it slips in the capstan.
>
> I've cleaned the capstan with everything from alcohol to Windex and it
> still slips.

Easy as 1-2-3:

1. Clean the pinch roller.
2. Check the pinch roller pressure, the supply reel tension, and the
takeup tension.
3. Replace the pinch roller.

Unless this is a well documented professional tape deck, you probably
don't have the specifications for tension adjustments, and some may not
be adjustable. But basically, you don't have a tape problem, you have a
tape deck service problem. Fix it.

[Carey Carlan]

Laurence Payne <lpayne1NOSPAM@dslDOTpipexDOTcom> wrote in
:

>>This is the trophy tape of my collection--a 1969 recital to be
>>presented at a 2006 performance by the same artist.
>
> Will other tapes play OK on that machine?

A Maxell shiny back plays correctly. I don't have many others as I always
used back coated tapes.

> As this is such an important recording, presumably you long ago made
> copies onto other media? How important is it that the tape copy
> survives?

I long ago didn't record it. I was 11 when this tape was made. I received
in a collection yesterday from a gentleman who passed away a couple of
years ago.

As it is the only known copy, it must survive.

[Carey Carlan]

Steve Urbach > wrote in
:

> Sounds like a shiny / hard pinch roller or insufficient pinch roller
> pressure.

I'll check that immediately. The pinch roller is old, but not terribly
stiff. I need to clean it and see if that helps.

[Carey Carlan]

"Mike Rivers" > wrote in
oups.com:

>> The culprit: 3M 203 tape 1 mil, not back coated.
>> The problem: My recorder won't pull it at speed. I'm getting wild
>> speed errors as it slips in the capstan.
>>
>> I've cleaned the capstan with everything from alcohol to Windex and
>> it still slips.
>
> Easy as 1-2-3:
>
> 1. Clean the pinch roller.
> 2. Check the pinch roller pressure, the supply reel tension, and the
> takeup tension.
> 3. Replace the pinch roller.
>
> Unless this is a well documented professional tape deck, you probably
> don't have the specifications for tension adjustments, and some may
> not be adjustable. But basically, you don't have a tape problem, you
> have a tape deck service problem. Fix it.

I'll do that.

Can you explain how a dry or dirty pinch roller would affect how well the
tape adheres to the capstan on the other side? Is it an "area of contact"
thing?

[Scott Dorsey]

Carey Carlan wrote:

> The culprit: 3M 203 tape 1 mil, not back coated.
> The problem: My recorder won't pull it at speed. I'm getting wild speed
> errors as it slips in the capstan.

Check your tape tension. If it's correct, replace the pinch roller. If
the pinch roller is more than five years old, replace it anyway. If you
have a spare pinch roller and it's been on the shelf for a decade, it's
bad. Throw it away and get a new one.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Scott Dorsey]

Carey Carlan > wrote:
>
>Can you explain how a dry or dirty pinch roller would affect how well the
>tape adheres to the capstan on the other side? Is it an "area of contact"
>thing?

The tape is driven both by the capstan on one side and the pinch roller
on the other side. If the pinch roller slips, you now have two different
things running at different speed, one on each side of the tape.

If the thing is marginal, it will be much worse with thinner tape.
One mil will be worse than 1.5, and half mil may not work at all. It will
also tend to be worse with tape that is stiffer and doesn't conform well
around the capstan; the Japanese tapes tend to have stiffer backing than
American and European tapes of the same thickness.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Carey Carlan]

(Scott Dorsey) wrote in
:

> Carey Carlan wrote:
>
>> The culprit: 3M 203 tape 1 mil, not back coated.
>> The problem: My recorder won't pull it at speed. I'm getting wild
>> speed errors as it slips in the capstan.
>
> Check your tape tension. If it's correct, replace the pinch roller.
> If the pinch roller is more than five years old, replace it anyway.
> If you have a spare pinch roller and it's been on the shelf for a
> decade, it's bad. Throw it away and get a new one.
> --scott

The pinch roller is original. This machine has been in mothballs for 22
years until its trip to the tech in July. It came back with a cleaned
roller, but that was a couple of dozen 20+ year old tapes ago.

On everyone's advice I pulled the pinch roller and cleaned it with the
same bottle of TEAC rubber cleaner/conditioner I've used for thirty odd
years. That helped some. Also, the shaft on which the pinch roller
rides was gummed with 28-year-old grease. Replaced that with my
venerable tube of phono lube. Again better. Flipped it around back to
front. That's now tolerable.

I don't expect to get a replacement in time as this has to be delivered
finished in 10 days.

Pioneer RXA-309 "Pinch roller assembly" no longer stocked.

"recaps" at Parts Express or Athan? Other sources?

[Scott Dorsey]

Carey Carlan > wrote:
>I don't expect to get a replacement in time as this has to be delivered
>finished in 10 days.
>
>Pioneer RXA-309 "Pinch roller assembly" no longer stocked.
>
>"recaps" at Parts Express or Athan? Other sources?

Yes, get a recap. Parts Express is fine. There is an outfit in the
midwest that is listed in the Ampex Mailing List Parts Suppliers guide
which is also pretty good, and probably cheaper.

Pinch rollers are disposable items. You need to change them regularly.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Mike Rivers]

Carey Carlan wrote:

> Can you explain how a dry or dirty pinch roller would affect how well the
> tape adheres to the capstan on the other side? Is it an "area of contact"
> thing?

I thnk so. The capstan drives the pinch roller as well as the tape. In
any case, you need a good pinch roller to get the tape to run
correctly.

[Richard Crowley]

"Carey Carlan" wrote ...
> Can you explain how a dry or dirty pinch roller would affect how well
> the
> tape adheres to the capstan on the other side? Is it an "area of
> contact"
> thing?

In addition to the obvious (glazed surface of the rubber),
I've seen pinch rollers that had a "groove" worn in them
right where the tape touches. It is concievable that old
brittle rubber, and any kind of surface deformity (like a
"groove") would reduce the amount of contact the pinch
roller has with the backside of the tape. I don't remember
the thickness of 3M 202. Could it be thinner than the other
vintage tapes you have been playing?

If you think about it, the capstan doesn't really pull the
tape. The surface of the capstan and of the tape are too
"shiny" for any kind of reasonable friction. That is why
the pinch roller plays a crucial part in the action.

[Tom Jancauskas]

in article , Carey Carlan at
wrote on 8/25/06 9:20 AM:

> (Scott Dorsey) wrote in
> :
>
>> Carey Carlan wrote:
>>
>>> The culprit: 3M 203 tape 1 mil, not back coated.
>>> The problem: My recorder won't pull it at speed. I'm getting wild
>>> speed errors as it slips in the capstan.
>>
>> Check your tape tension. If it's correct, replace the pinch roller.
>> If the pinch roller is more than five years old, replace it anyway.
>> If you have a spare pinch roller and it's been on the shelf for a
>> decade, it's bad. Throw it away and get a new one.
>> --scott
>
> The pinch roller is original. This machine has been in mothballs for 22
> years until its trip to the tech in July. It came back with a cleaned
> roller, but that was a couple of dozen 20+ year old tapes ago.
>
> On everyone's advice I pulled the pinch roller and cleaned it with the
> same bottle of TEAC rubber cleaner/conditioner I've used for thirty odd
> years. That helped some. Also, the shaft on which the pinch roller
> rides was gummed with 28-year-old grease. Replaced that with my
> venerable tube of phono lube. Again better. Flipped it around back to
> front. That's now tolerable.
>
> I don't expect to get a replacement in time as this has to be delivered
> finished in 10 days.
>
> Pioneer RXA-309 "Pinch roller assembly" no longer stocked.
>
> "recaps" at Parts Express or Athan? Other sources?


Here is a site I found

http://www.terrysrubberrollers.com/

I have no idea what quality of work they do, but it's a start.


--
Tom Jancauskas
Imedia

[Carey Carlan]

Tom Jancauskas > wrote in news:C1147D68.1F7BE%
:

>> I don't expect to get a replacement in time as this has to be delivered
>> finished in 10 days.
>>
>> Pioneer RXA-309 "Pinch roller assembly" no longer stocked.
>>
>> "recaps" at Parts Express or Athan? Other sources?
>
> Here is a site I found
>
> http://www.terrysrubberrollers.com/
>
> I have no idea what quality of work they do, but it's a start.

Thanks. I'll contact them as well. None of this will happen until
September as I can't have the machine down right now, even for as crucial a
repair as this. My timeline started back in June and that wasn't early
enough.

I have found another partial solution.

The original recording is on 7" reels. I discovered the problem playing to
another 7" reel. I tried playing onto 10" reel. No luck.

Going from a 10" supply reel to a 7" takeup reel has noticeably improved
the results. The recorder has a selector for large/small reels which
adjusts the reel tension. It's still on "small". I have no explanation,
just empirical results.

[Scott Dorsey]

Carey Carlan > wrote:
>
>The original recording is on 7" reels. I discovered the problem playing to
>another 7" reel. I tried playing onto 10" reel. No luck.
>
>Going from a 10" supply reel to a 7" takeup reel has noticeably improved
>the results. The recorder has a selector for large/small reels which
>adjusts the reel tension. It's still on "small". I have no explanation,
>just empirical results.

This is a sign the tape tension probably isn't adjusted right either. I
assume this machine doesn't have servo tension control?

Get a new pinch roller before you try and adjust anything, though.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Carey Carlan]

"Richard Crowley" > wrote in news:12eu4ktm4rpcmc4
@corp.supernews.com:

> In addition to the obvious (glazed surface of the rubber),
> I've seen pinch rollers that had a "groove" worn in them
> right where the tape touches. It is concievable that old
> brittle rubber, and any kind of surface deformity (like a
> "groove") would reduce the amount of contact the pinch
> roller has with the backside of the tape. I don't remember
> the thickness of 3M 202. Could it be thinner than the other
> vintage tapes you have been playing?

It feels like standard 1 mil.

It has one outstanding property. This is the oldest (1969) of any tape
I've worked with in this project. The Scotch 203 has left absolutely no
residue anywhere. Cleaning the heads and tape path yields a nearly
perfectly clean Q-tip after about 3 passes each on two tapes. Required
no baking or other pre-processing. If not for my recorder's inability to
play it at first, the 203 would have been by far the easiest transfer of
the collection.

The recording is just as stellar. No dropouts or hiccups.

> If you think about it, the capstan doesn't really pull the
> tape. The surface of the capstan and of the tape are too
> "shiny" for any kind of reasonable friction. That is why
> the pinch roller plays a crucial part in the action.

That makes sense, thanks.

[Richard Crowley]

"Carey Carlan" wrote ...
> "Richard Crowley" wrote
>> Could it be thinner than the other vintage tapes you have been playing?
>
> It feels like standard 1 mil.

I've always considerred 1.5 mil to be "standard" and
1 mil to be "long-playing / thin". And 0.5 mil is just
trouble on a reel.

[videochas www.locoworks.com]

Richard Crowley wrote:
>
> I've always considerred 1.5 mil to be "standard" and
> 1 mil to be "long-playing / thin". And 0.5 mil is just
> trouble on a reel.

I, too have been recently transferring old tapes to other media, and
strangely a reel of Scotch 290 (0.5 mil) that was 40 years old was no
trouble at all. Played like new. It was the 111 that gave me fits.

[Carey Carlan]

"Richard Crowley" > wrote in news:ecn8fo$8m9$1
@news01.intel.com:

> "Carey Carlan" wrote ...
>> "Richard Crowley" wrote
>>> Could it be thinner than the other vintage tapes you have been playing?
>>
>> It feels like standard 1 mil.
>
> I've always considerred 1.5 mil to be "standard" and
> 1 mil to be "long-playing / thin". And 0.5 mil is just
> trouble on a reel.

I meant that it didn't feel different from other 1 mil.

[Goaty]

Richard Crowley wrote:

> "Carey Carlan" wrote ...
>
>> Can you explain how a dry or dirty pinch roller would affect how well the
>> tape adheres to the capstan on the other side? Is it an "area of
>> contact"
>> thing?
>
>
> In addition to the obvious (glazed surface of the rubber),
> I've seen pinch rollers that had a "groove" worn in them
> right where the tape touches. It is concievable that old
> brittle rubber, and any kind of surface deformity (like a
> "groove") would reduce the amount of contact the pinch
> roller has with the backside of the tape.

Extreme last resort only:

if you can not get a replacement
if everything else does not work ...

Offset printers have a fluid called "blanket and roller reviver." It's
for those occasions where sh|t happens and you get a low spot in the
rubber[1] blanket you print off. You should replace the blanket, but in
the absence of a part, or being able to rotate the blanket 180, a dob of
this stuff on the offending area will cause the blanket to swell
slightly - enough to get the job through.

Given that the idea is to get the job out, then replace the blanket, god
only knows a) what long term effect it has on the rubber or b) whether
it will work as well on a pinch roller, but I know it is volatile and
leaves no residue on the surface, otherwise the printing would not be
possible.

The other possible problem is uneven "revival" causing a lumpy pich
roller, but the blankets do come back even.[2]

If you try this, let us know how it went ... :)

Cheers
Goaty

1. or synthetic or whatever - just using "rubber" as convenient shorthand.

2. I did say this was extreme last resort!
--
_--_|\ John Lamp - in beautiful downtown Highton
/ \ DoD#:1906 Ulysses#:10185 Vulcan Nomad
\_.--._/ Phone: 0409 512 254
v Hear no Evo, See no Evo, Fear no Evo

Militant Agnostic - I don't know and you don't either

[Carey Carlan]

Goaty > wrote in
:

> Extreme last resort only:
>
> if you can not get a replacement
> if everything else does not work ...
>
> Offset printers have a fluid called "blanket and roller reviver." It's
> for those occasions where sh|t happens and you get a low spot in the
> rubber[1] blanket you print off. You should replace the blanket, but
> in the absence of a part, or being able to rotate the blanket 180, a
> dob of this stuff on the offending area will cause the blanket to
> swell slightly - enough to get the job through.

Thanks, John. That sounds just a little too risky for my taste.

I have a decent copy of the wobbly tape now. These are the steps I took:

1) Cleaned the pinch roller with TEAC cleaner/conditioner.
2) Put the recorder in play with no tape and touch the roller with a fine
grit sandpaper to knock off the glaze.
3) Flipped the roller back to front.
4) Scrubbed the capstan one more time
5) Used a 10" reel on the supply side and 7" on the takeup.

These five steps tamed the wow to mostly unnoticeable levels.

I will have the roller retreaded as soon as this project ends. There are
other tapes yet to transfer, but they are all back-coated.

[Chris Hornbeck]

On Fri, 25 Aug 2006 14:20:14 GMT, Carey Carlan >
wrote:

>The pinch roller is original. This machine has been in mothballs for 22
>years until its trip to the tech in July. It came back with a cleaned
>roller, but that was a couple of dozen 20+ year old tapes ago.
>
>On everyone's advice I pulled the pinch roller and cleaned it with the
>same bottle of TEAC rubber cleaner/conditioner I've used for thirty odd
>years. That helped some.

Since this is an emergency, I've had very good luck in the
short term by buffing down to a newer surface by holding
the (removed) pinch roller in one hand, a sheet of 600
grit sandpaper face up on a flat surface in the other,
and doing what comes naturally.

Only lasts a while, but surprisingly good for that little
while.


> Also, the shaft on which the pinch roller
>rides was gummed with 28-year-old grease. Replaced that with my
>venerable tube of phono lube. Again better. Flipped it around back to
>front. That's now tolerable.

Might be a good idea to wash *all* of the old grease out
with a cotton swab and alcohol, if you haven't already.
Poor old stuff's more wax than grease these days. I know
how it feels.


>I don't expect to get a replacement in time as this has to be delivered
>finished in 10 days.

Hope yer successful. All good fortune,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[Edi Zubovic]

On Fri, 25 Aug 2006 15:48:01 GMT, Carey Carlan >
wrote:

-----------------------------8<------------------------
>Thanks. I'll contact them as well. None of this will happen until
>September as I can't have the machine down right now, even for as crucial a
>repair as this. My timeline started back in June and that wasn't early
>enough.
>
>I have found another partial solution.
>
>The original recording is on 7" reels. I discovered the problem playing to
>another 7" reel. I tried playing onto 10" reel. No luck.
>
>Going from a 10" supply reel to a 7" takeup reel has noticeably improved
>the results. The recorder has a selector for large/small reels which
>adjusts the reel tension. It's still on "small". I have no explanation,
>just empirical results.

--- And this suggests to me it's not the pinch roller problem only.
BTW, I am cleaning my roller using water and a mild household ie.
kitchen abrasive, it may have various trade names but essentially it's
a very fine aluminium oxide in an detergent solution. It should be
readily available everywhere. It cleans residues well, can restore
rubber grip and it's not as risky as using sanpaper, where one can
easily do some eccentric (sic!) harm.

Here, as Scott as usually points out right, can well be that the whole
tape transport should be checked, cleaned and re-lubricated again,
starting from the motors on. Synergies of a tape transport are so
delicate... check motor and other bearings well.

Edi Zubovic, Crikvenica, Croatia