Rubber idler wheel rubber restoration

[Jeff Liebermann]

I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.

Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?

In the 1960's I would just replace the rubber parts, so this was not
an issue. Now, I have to work with what's in front of me. Worse, I
have one shot to get it right and can't really risk a failed
experiment.

I've applied No-Slip goop to the outside of the idlers, which works
for a few hours and then starts to slip. That's not going to work.

I also have a bottle of foul smelling Methyl Prapasol Acetate, which I
use to clean and soften rubber parts in laser printers. It works well
for printers. However, my experience with the stuff on really old
rubber parts (over about 10-15 years) is that the rubber just
crumbles. I don't want to risk it.

Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?

[Sjouke Burry]

Post by Jeff Liebermann
I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.
Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?
In the 1960's I would just replace the rubber parts, so this was not
an issue. Now, I have to work with what's in front of me. Worse, I
have one shot to get it right and can't really risk a failed
experiment.
I've applied No-Slip goop to the outside of the idlers, which works
for a few hours and then starts to slip. That's not going to work.
I also have a bottle of foul smelling Methyl Prapasol Acetate, which I
use to clean and soften rubber parts in laser printers. It works well
for printers. However, my experience with the stuff on really old
rubber parts (over about 10-15 years) is that the rubber just
crumbles. I don't want to risk it.
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?

Take out the wheels, put new rubber on them, freeze them with
liquid nitrogen,or CO2 liquid spray, then machine the cold,
hard rubber to the proper dimensions.
You might have to re-cool occasionally.
I dont think you can apply some magic to the old,almost crumbling stuff.

[N Cook]

Post by Jeff Liebermann
I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.
Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?
In the 1960's I would just replace the rubber parts, so this was not
an issue. Now, I have to work with what's in front of me. Worse, I
have one shot to get it right and can't really risk a failed
experiment.
I've applied No-Slip goop to the outside of the idlers, which works
for a few hours and then starts to slip. That's not going to work.
I also have a bottle of foul smelling Methyl Prapasol Acetate, which I
use to clean and soften rubber parts in laser printers. It works well
for printers. However, my experience with the stuff on really old
rubber parts (over about 10-15 years) is that the rubber just
crumbles. I don't want to risk it.
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# http://www.LearnByDestroying.com AE6KS

A better description ,dimensions etc would help.
If they are the thin metal discs with rubber at the periphery of the rim
and returning over the disc, both sides, a few mm, then I have a fudge for
those.
Otherwise O rings are useful, don't usaually need to be flat , to work

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

[radiosrfun]

Post by Jeff Liebermann
I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.
Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?
In the 1960's I would just replace the rubber parts, so this was not
an issue. Now, I have to work with what's in front of me. Worse, I
have one shot to get it right and can't really risk a failed
experiment.
I've applied No-Slip goop to the outside of the idlers, which works
for a few hours and then starts to slip. That's not going to work.
I also have a bottle of foul smelling Methyl Prapasol Acetate, which I
use to clean and soften rubber parts in laser printers. It works well
for printers. However, my experience with the stuff on really old
rubber parts (over about 10-15 years) is that the rubber just
crumbles. I don't want to risk it.
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# http://www.LearnByDestroying.com AE6KS

I'm not sure if anything here would help - but I believe - MCM Electronics
sells a kit of some sort. Check with them.
They do have a web site - maybe you can go there to look up the "keyword".

[William Sommerwerck]

Google "rubber rejuvenator". There are a lot of products.

I've used Fedron (from Federal Mining and Manufacturing) successfully.

[Sam Goldwasser]

Post by William Sommerwerck
Google "rubber rejuvenator". There are a lot of products.
I've used Fedron (from Federal Mining and Manufacturing) successfully.

From the description, it doesn't sound like a rejuvenator will help.

Some photos would help to determine if an off-the-shelf rubber
tire, belt, or O-ring could be pressed into service here.

Also, isn't/wasn't there a place that would rebuild your rubber parts
on a custom basis?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

[William Sommerwerck]

Post by Sam Goldwasser
From the description, it doesn't sound like a rejuvenator will help.

Fedron will restore "hard as a rock" (the OP's description) rubber. Whether
it's the appropriate product for this particular purpose is not clear.

[Michael A. Terrell]

Post by Sam Goldwasser

Post by William Sommerwerck
Google "rubber rejuvenator". There are a lot of products.
I've used Fedron (from Federal Mining and Manufacturing) successfully.

From the description, it doesn't sound like a rejuvenator will help.
Some photos would help to determine if an off-the-shelf rubber
tire, belt, or O-ring could be pressed into service here.
Also, isn't/wasn't there a place that would rebuild your rubber parts
on a custom basis?

Are you thinking of PRB? They are long gone. What little is left is
now part of Russell Industries. http://www.russellind.com

They have a downloadable cross reference for availaible parts at:
http://www.russellind.com/prbline/licensing_agreement.htm I haven't
installed it, but I will compare it to the old printed version I have on
hand.

[c***@webtv.net]

Been there and done that too, Michael A. Terrell.Vietnam 1964.
www.114thaviationcompany.com www.tsna.org
www.angelfire.com/md2/Ldotvets (Page tree, tain)

I have my DD 14 to prove it too.
cuhulin

[Sam Goldwasser]

Post by Michael A. Terrell

Post by Sam Goldwasser

Post by William Sommerwerck
Google "rubber rejuvenator". There are a lot of products.
I've used Fedron (from Federal Mining and Manufacturing) successfully.

From the description, it doesn't sound like a rejuvenator will help.
Some photos would help to determine if an off-the-shelf rubber
tire, belt, or O-ring could be pressed into service here.
Also, isn't/wasn't there a place that would rebuild your rubber parts
on a custom basis?

Are you thinking of PRB? They are long gone. What little is left is
now part of Russell Industries. http://www.russellind.com

Yeah, that was probably it. I think someone else suggested another place
that has a similar service.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

Post by Michael A. Terrell
http://www.russellind.com/prbline/licensing_agreement.htm I haven't
installed it, but I will compare it to the old printed version I have on
hand.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.
Michael A. Terrell
Central Florida

[Ken Layton]

The "PRB Line" section at Russell Industries still does rebuilds.
Check out this:

http://www.russellind.com/client/download/rebuild.pdf

[Michael A. Terrell]

Post by Ken Layton
The "PRB Line" section at Russell Industries still does rebuilds.
http://www.russellind.com/client/download/rebuild.pdf

That looks like a page out of their mid '70s paper catalog. How did
you find it? Most of the links of the Russell website are dead, and
most good pages are dated 2002.

[Ken Layton]

Post by Ken Layton
The "PRB Line" section at Russell Industries still does rebuilds.
http://www.russellind.com/client/download/rebuild.pdf

   That looks like a page out of their mid '70s paper catalog.  How did
you find it?  Most of the links of the Russell website are dead, and
most good pages are dated 2002.

I went to: http://www.russellind.com/index1.htm

Then "download" and then PRB Line catalog.

[Michael A. Terrell]

Post by Ken Layton

Post by Michael A. Terrell

Post by Ken Layton
The "PRB Line" section at Russell Industries still does rebuilds.
http://www.russellind.com/client/download/rebuild.pdf

That looks like a page out of their mid '70s paper catalog. How did
you find it? Most of the links of the Russell website are dead, and
most good pages are dated 2002.

I went to: http://www.russellind.com/index1.htm
Then "download" and then PRB Line catalog.

That link was dead when I tried it, yesterday. I got a 404 error.
It's working tonight.

[Ken G.]

All the rejuvenating stuff will not work or will not last long .

If you have some VCR belts around that will fit around the hard idler .
A real thin one the same width would be deal but 1 or 2 of the square
ones will work .

Stretch or place the belt-s around the idler and run a bead of superglue
around to hold it on . mount the idler in a drill and run it on
sandpaper .
If you are using square belt-s you shound sand it down in the drill
first to take some off so the finished diameter is closer .

This works for me 100%

[msg]

Post by Ken G.
All the rejuvenating stuff will not work or will not last long .
If you have some VCR belts around that will fit around the hard idler .
A real thin one the same width would be deal but 1 or 2 of the square
ones will work .
Stretch or place the belt-s around the idler and run a bead of superglue
around to hold it on . mount the idler in a drill and run it on
sandpaper .
If you are using square belt-s you shound sand it down in the drill
first to take some off so the finished diameter is closer .
This works for me 100%

Nice hearing the various techniques mentioned in this thread. I have
restored digital tape transport capstans by removing the deteriorated
rubber and layering back to the original diameter using multiple dips
in liquid vinyl; the capstan needs to be spun at low rpm with the shaft
horizontal until each vinyl layer has set. I did a capstan for an
HP-85 awhile ago that required quite close tolerances and this technique
worked well; the result was a bright red surface however ;-)

Regards,

Michael

[Jeff Liebermann]

Post by msg
Nice hearing the various techniques mentioned in this thread. I have
restored digital tape transport capstans by removing the deteriorated
rubber and layering back to the original diameter using multiple dips
in liquid vinyl; the capstan needs to be spun at low rpm with the shaft
horizontal until each vinyl layer has set. I did a capstan for an
HP-85 awhile ago that required quite close tolerances and this technique
worked well; the result was a bright red surface however ;-)

The HP85 drive roller is mostly metal with a relatively thin coating
of rubber. See photos at:
<http://www.voidware.com/calcs/hp85rep.htm>
See page 2 of 3 pages. Resurfacing such a roller will work just fine.
However, the Sony and Gerrard idlers have a much thicker layer of
rubber. The deformation depth of the capstan is also substantially
deeper than the HP85 drive roller, requiring a much thicker deposition
of added rubber. It's probably possible, using the suggested freezing
the rubber and machining it down to the diameter required. As I
indicated in a previous message, I think it will work with the
relatively wide Sony idler, but will not work with the fairly narrow
Gerrard idler.

Current status is that I'm gathering an assortment of chemicals and
concoctions, along with a variety of rubber parts. I'll try some
experiments next weekend, and then apply the least disgusting fix to
the customers antique tape recorder and turntable.

Thanks for all the suggestions and hints.

Incidentally, this is how I repaired an HP65 calculator drive roller:
<http://802.11junk.com/jeffl/pics/hp65/slides/Hp65-Drive-Roller.html>
The "rubber" is a piece of vinyl tubing, conveniently with the correct
diameter. The only good way to cut it to size is with a razor blade.

[Michael A. Terrell]

Post by Jeff Liebermann
I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.
Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?
In the 1960's I would just replace the rubber parts, so this was not
an issue. Now, I have to work with what's in front of me. Worse, I
have one shot to get it right and can't really risk a failed
experiment.
I've applied No-Slip goop to the outside of the idlers, which works
for a few hours and then starts to slip. That's not going to work.
I also have a bottle of foul smelling Methyl Prapasol Acetate, which I
use to clean and soften rubber parts in laser printers. It works well
for printers. However, my experience with the stuff on really old
rubber parts (over about 10-15 years) is that the rubber just
crumbles. I don't want to risk it.
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?

Try news:rec.antiques.radio+phono Old rubber is a common problem, and
several people there rebuild rubber drives.

http://groups.google.com/group/rec.antiques.radio+phono?hl=en for google
group users.

[DJM]

Try xyol (xylene) the paint thinner. I was told by a Xerox repairman they
used it on copier rollers when they got hard.

I have used it and works for me.

Dave

Post by Michael A. Terrell

Post by Jeff Liebermann
I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.
Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?
In the 1960's I would just replace the rubber parts, so this was not
an issue. Now, I have to work with what's in front of me. Worse, I
have one shot to get it right and can't really risk a failed
experiment.
I've applied No-Slip goop to the outside of the idlers, which works
for a few hours and then starts to slip. That's not going to work.
I also have a bottle of foul smelling Methyl Prapasol Acetate, which I
use to clean and soften rubber parts in laser printers. It works well
for printers. However, my experience with the stuff on really old
rubber parts (over about 10-15 years) is that the rubber just
crumbles. I don't want to risk it.
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?

Try news:rec.antiques.radio+phono Old rubber is a common problem, and
several people there rebuild rubber drives.
http://groups.google.com/group/rec.antiques.radio+phono?hl=en for google
group users.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.
Michael A. Terrell
Central Florida

[James Sweet]

Post by DJM
Try xyol (xylene) the paint thinner. I was told by a Xerox repairman they
used it on copier rollers when they got hard.
I have used it and works for me.

Zippo lighter fluid apparently works too, my friend soaks hardened rubber
parts in it. When they get really bad there's not much you can do other than
replace them though.

[Mike S.]

Post by DJM
Try xyol (xylene) the paint thinner. I was told by a Xerox repairman they
used it on copier rollers when they got hard.
I have used it and works for me.

Yep.

TEAC used to sell a rubber rejuvenator for cassette decks that was
essentially xylene. A suitable substitute can be bought in the US as a
paint/gunk remover called "goof off" in the yellow metal can.

[Mr. Land]

Post by Mike S.

Try xyol (xylene) the paint thinner.  I was told by a Xerox repairman they
used it on copier rollers when they got hard.
I have used it and works for me.

Yep.
TEAC used to sell a rubber rejuvenator for cassette decks that was
essentially xylene. A suitable substitute can be bought in the US as a
paint/gunk remover called "goof off" in the yellow metal can.

Finally. Someone named a product after me.

[Mr. Land]

Post by Jeff Liebermann
I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.
Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?
In the 1960's I would just replace the rubber parts, so this was not
an issue. Now, I have to work with what's in front of me. Worse, I
have one shot to get it right and can't really risk a failed
experiment.
I've applied No-Slip goop to the outside of the idlers, which works
for a few hours and then starts to slip. That's not going to work.
I also have a bottle of foul smelling Methyl Prapasol Acetate, which I
use to clean and soften rubber parts in laser printers. It works well
for printers. However, my experience with the stuff on really old
rubber parts (over about 10-15 years) is that the rubber just
crumbles. I don't want to risk it.
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
#http://www.LearnByDestroying.com AE6KS

Are they "slippery" hard or "brittle" hard? Can you see any cracks
on the drive surfaces? If they are brittle hard w/ major cracking
(i.e. cracks that run into the rubber below the drive surfaces) I
would
be surprised if you could find any chemical that will help.

If they're not that bad, I've had good luck with GC Electronics
Rubber Rejuvenator.

For really, really hardened rubber I've had success with
Teac Rubber Cleaner (Part No. RC-2). This a potent,
oily liquid that smells like liquid moth balls. I found a
discussion thread that indicates it is no longer made,
but it looks like Rawn makes a close replacement:

"...
I've used the old TEAC rubber conditioner since about 1979 and I still
have about 1/2 oz left of an old 2 oz glass bottle. That's how far it
goes when used in moderation. That was my favorite for pinch rollers.
The bad news is TEAC doesn't sell it anymore. The good news is it was
made for TEAC by Rawn and they still sell the latest incarnation as
"Re-Grip" They changed the formula a couple times because someone in
California found some chemical in it to be carcinogenic. But none of
my tape decks have gotten cancer, so I guess the joke's on
California.

http://www.aedwis.com/rawn.html

..."

I still have a mostly-full 7 oz can of the Teac cleaner from 20 yrs.
ago. Guess I'll keep the cap on it...

[Jeff Liebermann]

Post by Mr. Land

Post by Jeff Liebermann
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?

Are they "slippery" hard or "brittle" hard?

Slippery hard. I spun both idlers while burnishing with fine emery
cloth to roughen the surface. That's helped, but without the
compression provided by the normally springy rubber, the turntable and
tape recorder both still slipped. Also, no flat spots.

The idler in the Gerrard turntable looks like the top row, 2nd from
right:
<http://www.turntablebasics.com/idlerwheels.html>

Post by Mr. Land
Can you see any cracks on the drive surfaces?

No cracks. It's not like they're ready to crumble or fall apart. The
rubber is intact, but hard as a rock. I didn't photograph the idlers
but can do so when I return to the scene of the crime, er... customer,
because there's no obvious damage. Just a hardening of the rubber.

Others have suggested machining it down and adding a layer of new
rubber from a belt or rubber sheet. I've done that in the past and it
works. It might work with the Sony idler, which is quite wide.
However, the Gerrard turntable idler is only about 2mm wide at the
point of contact, and will therefore be difficult to resurface.

Post by Mr. Land
If they are brittle hard w/ major cracking
(i.e. cracks that run into the rubber below the drive surfaces) I
would
be surprised if you could find any chemical that will help.

Well, I may be lucky here as there is no obvious cracking. However, I
suspect if I bend the rubber sufficiently, it will crack instead of
stretch.

Post by Mr. Land
If they're not that bad, I've had good luck with GC Electronics
Rubber Rejuvenator.

I've tried the stuff in the past. Like the other rubber cleaners,
rejuvenators, restorers, and recovery compounds, it softens only
surface of the rubber. My guess(tm) is about 0.3mm deep at most. The
rubber is not porous so the solvent only affects the surface. What
I'm looking for is something that has a sufficiently small molecular
diameter to penetrate deeper than just the surface.

Post by Mr. Land
For really, really hardened rubber I've had success with
Teac Rubber Cleaner (Part No. RC-2). This a potent,
oily liquid that smells like liquid moth balls. I found a
discussion thread that indicates it is no longer made,

Sounds interesting. I'll see if I can find some. Moth ball stench
would be a naphthalene. That can probably be found at the hardware
store.

Post by Mr. Land
"...
I've used the old TEAC rubber conditioner since about 1979 and I still
have about 1/2 oz left of an old 2 oz glass bottle. That's how far it
goes when used in moderation. That was my favorite for pinch rollers.
The bad news is TEAC doesn't sell it anymore. The good news is it was
made for TEAC by Rawn and they still sell the latest incarnation as
"Re-Grip" They changed the formula a couple times because someone in
California found some chemical in it to be carcinogenic. But none of
my tape decks have gotten cancer, so I guess the joke's on
California.
http://www.aedwis.com/rawn.html
..."
I still have a mostly-full 7 oz can of the Teac cleaner from 20 yrs.
ago. Guess I'll keep the cap on it...

I'll probably order some tomorrow.
<http://www.longselectronics.com/product.jsp?path=-1%7C12565&id=1194>
<http://www.mcminone.com/product.asp?product_id=20-230&catalog_name=MCMProducts>

I just found a box of ancient idlers and belts to practice on. I've
got about a week to tinker before attacking the antiques.

[N Cook]

Post by Jeff Liebermann

Post by Mr. Land

Post by Jeff Liebermann
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?

Are they "slippery" hard or "brittle" hard?

Slippery hard. I spun both idlers while burnishing with fine emery
cloth to roughen the surface. That's helped, but without the
compression provided by the normally springy rubber, the turntable and
tape recorder both still slipped. Also, no flat spots.
The idler in the Gerrard turntable looks like the top row, 2nd from
<http://www.turntablebasics.com/idlerwheels.html>

Post by Mr. Land
Can you see any cracks on the drive surfaces?

No cracks. It's not like they're ready to crumble or fall apart. The
rubber is intact, but hard as a rock. I didn't photograph the idlers
but can do so when I return to the scene of the crime, er... customer,
because there's no obvious damage. Just a hardening of the rubber.
Others have suggested machining it down and adding a layer of new
rubber from a belt or rubber sheet. I've done that in the past and it
works. It might work with the Sony idler, which is quite wide.
However, the Gerrard turntable idler is only about 2mm wide at the
point of contact, and will therefore be difficult to resurface.

Post by Mr. Land
If they are brittle hard w/ major cracking
(i.e. cracks that run into the rubber below the drive surfaces) I
would
be surprised if you could find any chemical that will help.

Well, I may be lucky here as there is no obvious cracking. However, I
suspect if I bend the rubber sufficiently, it will crack instead of
stretch.

Post by Mr. Land
If they're not that bad, I've had good luck with GC Electronics
Rubber Rejuvenator.

I've tried the stuff in the past. Like the other rubber cleaners,
rejuvenators, restorers, and recovery compounds, it softens only
surface of the rubber. My guess(tm) is about 0.3mm deep at most. The
rubber is not porous so the solvent only affects the surface. What
I'm looking for is something that has a sufficiently small molecular
diameter to penetrate deeper than just the surface.

Post by Mr. Land
For really, really hardened rubber I've had success with
Teac Rubber Cleaner (Part No. RC-2). This a potent,
oily liquid that smells like liquid moth balls. I found a
discussion thread that indicates it is no longer made,

Sounds interesting. I'll see if I can find some. Moth ball stench
would be a naphthalene. That can probably be found at the hardware
store.

Post by Mr. Land
"...
I've used the old TEAC rubber conditioner since about 1979 and I still
have about 1/2 oz left of an old 2 oz glass bottle. That's how far it
goes when used in moderation. That was my favorite for pinch rollers.
The bad news is TEAC doesn't sell it anymore. The good news is it was
made for TEAC by Rawn and they still sell the latest incarnation as
"Re-Grip" They changed the formula a couple times because someone in
California found some chemical in it to be carcinogenic. But none of
my tape decks have gotten cancer, so I guess the joke's on
California.
http://www.aedwis.com/rawn.html
..."
I still have a mostly-full 7 oz can of the Teac cleaner from 20 yrs.
ago. Guess I'll keep the cap on it...

I'll probably order some tomorrow.
<http://www.longselectronics.com/product.jsp?path=-1%7C12565&id=1194>

<http://www.mcminone.com/product.asp?product_id=20-230&catalog_name=MCMProdu
cts>

Post by Jeff Liebermann
I just found a box of ancient idlers and belts to practice on. I've
got about a week to tinker before attacking the antiques.
--
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

When you've failed with the gooey stuff.
This is what I've done for a Beogram idler.
I assume from the pics you directed to , that it is based on a thin metal
disc.
I cut a strip of moped inner tube, left the original ribber moulding in
place just in case my fudge did not work, seriously stretched the moped
rubber over the pulley rim and glued in place.
There was axial room to allow for the greater thickness and adjusted for the
change in "gear ratio" at the adjuster cone mechanism

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

[John]

I have had some success by boiling idlers and belts in water for a few
minuets
Costs nothing to drop an idler in a pan of water, give it a try.
Cheers John.

Post by Jeff Liebermann

Post by Jeff Liebermann

Post by Mr. Land

Post by Jeff Liebermann
Duz anyone have a better potion, elixer, process, or incantation for
softening rubber idler wheels?

Are they "slippery" hard or "brittle" hard?

Slippery hard. I spun both idlers while burnishing with fine emery
cloth to roughen the surface. That's helped, but without the
compression provided by the normally springy rubber, the turntable and
tape recorder both still slipped. Also, no flat spots.
The idler in the Gerrard turntable looks like the top row, 2nd from
<http://www.turntablebasics.com/idlerwheels.html>

Post by Mr. Land
Can you see any cracks on the drive surfaces?

No cracks. It's not like they're ready to crumble or fall apart. The
rubber is intact, but hard as a rock. I didn't photograph the idlers
but can do so when I return to the scene of the crime, er... customer,
because there's no obvious damage. Just a hardening of the rubber.
Others have suggested machining it down and adding a layer of new
rubber from a belt or rubber sheet. I've done that in the past and it
works. It might work with the Sony idler, which is quite wide.
However, the Gerrard turntable idler is only about 2mm wide at the
point of contact, and will therefore be difficult to resurface.

Post by Mr. Land
If they are brittle hard w/ major cracking
(i.e. cracks that run into the rubber below the drive surfaces) I
would
be surprised if you could find any chemical that will help.

Well, I may be lucky here as there is no obvious cracking. However, I
suspect if I bend the rubber sufficiently, it will crack instead of
stretch.

Post by Mr. Land
If they're not that bad, I've had good luck with GC Electronics
Rubber Rejuvenator.

I've tried the stuff in the past. Like the other rubber cleaners,
rejuvenators, restorers, and recovery compounds, it softens only
surface of the rubber. My guess(tm) is about 0.3mm deep at most. The
rubber is not porous so the solvent only affects the surface. What
I'm looking for is something that has a sufficiently small molecular
diameter to penetrate deeper than just the surface.

Post by Mr. Land
For really, really hardened rubber I've had success with
Teac Rubber Cleaner (Part No. RC-2). This a potent,
oily liquid that smells like liquid moth balls. I found a
discussion thread that indicates it is no longer made,

Sounds interesting. I'll see if I can find some. Moth ball stench
would be a naphthalene. That can probably be found at the hardware
store.

Post by Mr. Land
"...
I've used the old TEAC rubber conditioner since about 1979 and I still
have about 1/2 oz left of an old 2 oz glass bottle. That's how far it
goes when used in moderation. That was my favorite for pinch rollers.
The bad news is TEAC doesn't sell it anymore. The good news is it was
made for TEAC by Rawn and they still sell the latest incarnation as
"Re-Grip" They changed the formula a couple times because someone in
California found some chemical in it to be carcinogenic. But none of
my tape decks have gotten cancer, so I guess the joke's on
California.
http://www.aedwis.com/rawn.html
..."
I still have a mostly-full 7 oz can of the Teac cleaner from 20 yrs.
ago. Guess I'll keep the cap on it...

I'll probably order some tomorrow.
<http://www.longselectronics.com/product.jsp?path=-1%7C12565&id=1194>

<http://www.mcminone.com/product.asp?product_id=20-230&catalog_name=MCMProdu
cts>

Post by Jeff Liebermann
I just found a box of ancient idlers and belts to practice on. I've
got about a week to tinker before attacking the antiques.
--
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

When you've failed with the gooey stuff.
This is what I've done for a Beogram idler.
I assume from the pics you directed to , that it is based on a thin metal
disc.
I cut a strip of moped inner tube, left the original ribber moulding in
place just in case my fudge did not work, seriously stretched the moped
rubber over the pulley rim and glued in place.
There was axial room to allow for the greater thickness and adjusted for the
change in "gear ratio" at the adjuster cone mechanism
--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

[Colin Horsley]

Post by Jeff Liebermann
I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.
Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?

Post by Jeff Liebermann
Duz anyone have a better potion, elixer, process, or incantation for

softening rubber idler wheels?

I have used Rubber Roller Restorer from www.fixyourownprinter.com

http://www.fixyourownprinter.com/specials/misc/all/S03

Fixes printer rubber rollers etc etc.
Colin

[t***@gmail.com]

Post by Jeff Liebermann
I've been volunteered to resurrect a Gerard A75 turntable and a Sony
250 reel to reel tape deck.
Both the turntable and tape recorder have rubber idler wheels that
have turned hard as a rock. Is it possible to soften the rubber with
some chemical?

About 25 years ago, I had a Nordmende pinch roller that didn't respond
to the usual surface treatments, so a coworker tried TCE or MEK. The
trick was that he used either heat and/or pressure/vacuum (don't
remember anymore what the chamber was) to induce the TCE to
penetrate. After the TCE the pinch roller was clean and pliable, but
shrunken. So I followed another recommendation to soak it in brake
fluid, and sure enough, it plumped right up. YMMV, no warranty
expressed or implied, etc.

TM