Elmer's Rubber Cement is not the vulcanizing kind!

On 27 Apr, 04:08, (Tom Keats) wrote:
In article ,
* * * * Ablang writes:



I bought a 4oz jar (UPC 0 269050 8) of this stuff from Home Depot last
year for about $2.50. *Pretty cheap stuff.

I finally got a chance to use these on my inner tubes for my 27" x
1-1/4" tires (100 psi) and found out that they don't really stick
permanently. *The next day I discover that some part of the patch has
breached.

In trying to figure out what I did wrong (I have successfully patched
other tires before using the glue from patch kits), I figure it's that
I'm either using too thick of a layer of Elmer's or that this rubber
cement really isn't the vulcanizing kind.

What do you guys think?

Where can I buy (in bulk) a large amount of the vulcanizing cement
from at the best price?

Y'see what a Pandora's can o' worms you've opened? * ;-) *;-) *;-)

Might as well have started another chain cleaning/lubrication thread.


Might have already happened.

In article ,
jim beam writes:
Martin Riddle wrote:
"Tom Keats" wrote in message
...
In article ,
Tom Sherman writes:
Ablang ? wrote:
I bought a 4oz jar (UPC 0 269050 8) of this stuff from Home Depot
last
year for about $2.50. Pretty cheap stuff.

I finally got a chance to use these on my inner tubes for my 27" x
1-1/4" tires (100 psi) and found out that they don't really stick
permanently. The next day I discover that some part of the patch
has
breached.

In trying to figure out what I did wrong (I have successfully
patched
other tires before using the glue from patch kits), I figure it's
that
I'm either using too thick of a layer of Elmer's or that this rubber
cement really isn't the vulcanizing kind.

What do you guys think?

Where can I buy (in bulk) a large amount of the vulcanizing cement
from at the best price?
I was under the impression that vulcanizing requires heat and a
curative
to produce cross-linking of the polymers, and "vulcanizing fluid" is
a
marketing term.
As I understand it, so-called "vulcanizing" rubber cement
chemically integrates with the existing rubber to which
it is applied. This effect should be desirable with
regard to tire repairs, since holes in tires are external
and thereby exposed to all kinds of stresses and tensions.

I've long been under the impression that patch kit cement
is of the vulcanizing kind, but upon further research I'm
prepared to admit to error on my part.

If patch kit rubber cement truly is non-vulcanizing, it
nevertheless works for inner tube patches when it's properly
applied, the layers of cement are allowed to set ("cure")
for a few minutes before applying patch to hole, and the
patched tube is rested overnight before inflating.

I suspect the reason for letting the cement dry for a
few minutes before sticking the patch on, is to let it
become more viscous so that Surface Tension pulls (pushes?)
the patch more firmly into place against the tube. I think
the "good" rubber cement for tube patching has a solvent
in it, like acetone or some kind of pentane or other volatile
solvent who's job is to keep it storable & fluid enough
to spread it, and that's the solvent's only purpose. Once
the cement is applied, the next step is to let that solvent
evaporate so the remaining cement can do it's job.

I might be wrong about that, too -- I'm just guessing.
Maybe Jobst will set us all straight.

Maybe it's better to patch inner tubes during a rainy day,
when the air pressure is higher? Surface tension, 'n
all that.


cheers,
Tom


I just looked at a jar of Elmer's Rubber cement and it contains
N-Heptane.
As opposed to the tube of cement I have from Aid Auto, that has Heptane.
Which by chance is also known as N-Heptane.
I doubt that rubber cement actually has different flavors, but in this
context of repairing a inner tube, it�s the same.

There no such thing as cold vulcanization, room temperature yes, but its
RTV.
http://en.wikipedia.org/wiki/Vulcanization

If you want to Vulcanize a patch you need the vulcanizing hot patch kit
and watch the flames. (which is kinda fun)
Here's an example
http://www.advrider.com/forums/showthread.php?t=419095
The Allmighty EPA in the US has banned these, so us Americans are out of
luck.

Even the Park Vulcanizing patch kit is just rubber cement (heptane) and
a patch with some orange polymer that sticks pretty good after turning
to mush from the heptane.

dude, heptane is just the solvent. doesn't mean **** about the bonding
ingredients.

There are no bonding ingredients. Sticking patches onto tubes
is allegedly a non-chemical process, so there is thereby no
bonding involved.

Rubber cement is just gum with tiny fingers that somehow
squirm around, feeling for molecular fingerholds into which
to install themselves. Abracadabra.


cheers,
Tom

--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca

Tom Keats wrote:
In article ,
jim beam writes:
Martin Riddle wrote:
"Tom Keats" wrote in message
...
In article ,
Tom Sherman writes:
Ablang ? wrote:
I bought a 4oz jar (UPC 0 269050 8) of this stuff from Home Depot
last
year for about $2.50. Pretty cheap stuff.

I finally got a chance to use these on my inner tubes for my 27" x
1-1/4" tires (100 psi) and found out that they don't really stick
permanently. The next day I discover that some part of the patch
has
breached.

In trying to figure out what I did wrong (I have successfully
patched
other tires before using the glue from patch kits), I figure it's
that
I'm either using too thick of a layer of Elmer's or that this rubber
cement really isn't the vulcanizing kind.

What do you guys think?

Where can I buy (in bulk) a large amount of the vulcanizing cement
from at the best price?
I was under the impression that vulcanizing requires heat and a
curative
to produce cross-linking of the polymers, and "vulcanizing fluid" is
a
marketing term.
As I understand it, so-called "vulcanizing" rubber cement
chemically integrates with the existing rubber to which
it is applied. This effect should be desirable with
regard to tire repairs, since holes in tires are external
and thereby exposed to all kinds of stresses and tensions.

I've long been under the impression that patch kit cement
is of the vulcanizing kind, but upon further research I'm
prepared to admit to error on my part.

If patch kit rubber cement truly is non-vulcanizing, it
nevertheless works for inner tube patches when it's properly
applied, the layers of cement are allowed to set ("cure")
for a few minutes before applying patch to hole, and the
patched tube is rested overnight before inflating.

I suspect the reason for letting the cement dry for a
few minutes before sticking the patch on, is to let it
become more viscous so that Surface Tension pulls (pushes?)
the patch more firmly into place against the tube. I think
the "good" rubber cement for tube patching has a solvent
in it, like acetone or some kind of pentane or other volatile
solvent who's job is to keep it storable & fluid enough
to spread it, and that's the solvent's only purpose. Once
the cement is applied, the next step is to let that solvent
evaporate so the remaining cement can do it's job.

I might be wrong about that, too -- I'm just guessing.
Maybe Jobst will set us all straight.

Maybe it's better to patch inner tubes during a rainy day,
when the air pressure is higher? Surface tension, 'n
all that.


cheers,
Tom

I just looked at a jar of Elmer's Rubber cement and it contains
N-Heptane.
As opposed to the tube of cement I have from Aid Auto, that has Heptane.
Which by chance is also known as N-Heptane.
I doubt that rubber cement actually has different flavors, but in this
context of repairing a inner tube, it�s the same.

There no such thing as cold vulcanization, room temperature yes, but its
RTV.
http://en.wikipedia.org/wiki/Vulcanization

If you want to Vulcanize a patch you need the vulcanizing hot patch kit
and watch the flames. (which is kinda fun)
Here's an example
http://www.advrider.com/forums/showthread.php?t=419095
The Allmighty EPA in the US has banned these, so us Americans are out of
luck.

Even the Park Vulcanizing patch kit is just rubber cement (heptane) and
a patch with some orange polymer that sticks pretty good after turning
to mush from the heptane.

dude, heptane is just the solvent. doesn't mean **** about the bonding
ingredients.

There are no bonding ingredients. Sticking patches onto tubes
is allegedly a non-chemical process, so there is thereby no
bonding involved.

Rubber cement is just gum with tiny fingers that somehow
squirm around, feeling for molecular fingerholds into which
to install themselves. Abracadabra.


cheers,
Tom


ok, you can't read. 'nuff said.

On Apr 26, 6:55*pm, wrote:
Michael Press wrote:
Remove a well adhered patch. *You will see no indication of chemical
bond formation.

I find a well adhered patch not removable without heating. *Heating
affects the REMA patch orange rubber more than the tube rubber so they
separate with careful pulling. *I have not cared what remains on the
contact surface (it looks clean to me) before applying a new patch and
allowing it to cure.

I have also removed quite a few patches using a suitable solvent -
toluene and xylene are two that work.
The hard part seems to be getting a patch edge lifted to gain acces
to the tube/patch interface. Once that is accomplished the rest is
easy using a slow "peeling" technique in conjunction with more solvent
(think "cotton swab"). Even well adhered patches will come off clean
leaving no sign that there was ever a patch adhered/bonded there.

Everyone seems to agree on that last detail.
DR

In article ,
writes:
Michael Press wrote:

Now I'm wondering how those long polymers find their ways into
their holes or ruts or whatever allows them to interdigitate -- do
they just fall in when a hole opens up beneath them, or do they
just randomly flow around until they drop into a hole/rut/whatever?
If they're electrically drawn in, could that arguably be a chemical
process?

Physically it is similar to interleaving the pages of two books.
The force to pull them apart is enormous. It is not a chemical
process because chemical bonds are not changed. Very roughly, a
chemical bond changes when one or more electrons move permanently
from one orbit to another.

Vulcanizing rubber is a one way street chemically. Rubber is melted
with sulfur whence cross links form between polymers. This cross
linking cannot be undone to get back to the original constituents.

This sounds as though a REMA patch, once vulcanized, cannot be
removed. I find heating the patch on a flat surface (frying pan under
thumb pressure) to be an effective way of making well cured patches
removable. From all the chemistry in this thread, it seems my method
of applying the REMA patch, as soon as the vulcanizing fluid is no
^^^^^^^^^^^^^^^^^^^^^


In this discussion, some folks seem to refute that liquid vulcanizing
agents can coexist with rubber cement in the same off-the-shelf
container. There seems to be a lot of semantically induced confusion.

longer liquid, seems to be more conducive to polymerizing than waiting
for it to completely dry and before use, allowing patches to become
well adhered in several hours, seems also to be borne out.

In any event, having removed many leaky patches, that were ridden
immediately after patching, has shown me that they lift off, almost to
their edge as I described, developing a domed pocket containing talcum
from inside the inner tube.

And yet a well-applied patch snuggles right up to its inner tube.

It doesn't just sit there -- it appears to be firmly /pressed/ on,
despite no clamp or vise being used. And that's what piques my
curiosity.

Whatever simply sticks a patch onto a tube can be readily explained.
Heck, anyone can stick a Rice Crispy square onto an inner tube.

I'd just like to know what pushes or pulls a patch so securely
and firmly onto a tube. And I'm talking about naked tubes that
have been patched and then slung over the back of a chair overnight,
without being installed in a tire. That patch is on there like
a suction cup.


cheers,
Tom

--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca

Tom Keats wrote:
In article ,
writes:
Michael Press wrote:

Now I'm wondering how those long polymers find their ways into
their holes or ruts or whatever allows them to interdigitate -- do
they just fall in when a hole opens up beneath them, or do they
just randomly flow around until they drop into a hole/rut/whatever?
If they're electrically drawn in, could that arguably be a chemical
process?
Physically it is similar to interleaving the pages of two books.
The force to pull them apart is enormous. It is not a chemical
process because chemical bonds are not changed. Very roughly, a
chemical bond changes when one or more electrons move permanently
from one orbit to another.
Vulcanizing rubber is a one way street chemically. Rubber is melted
with sulfur whence cross links form between polymers. This cross
linking cannot be undone to get back to the original constituents.
This sounds as though a REMA patch, once vulcanized, cannot be
removed. I find heating the patch on a flat surface (frying pan under
thumb pressure) to be an effective way of making well cured patches
removable. From all the chemistry in this thread, it seems my method
of applying the REMA patch, as soon as the vulcanizing fluid is no
^^^^^^^^^^^^^^^^^^^^^


In this discussion, some folks seem to refute that liquid vulcanizing
agents can coexist with rubber cement in the same off-the-shelf
container. There seems to be a lot of semantically induced confusion.

longer liquid, seems to be more conducive to polymerizing than waiting
for it to completely dry and before use, allowing patches to become
well adhered in several hours, seems also to be borne out.

In any event, having removed many leaky patches, that were ridden
immediately after patching, has shown me that they lift off, almost to
their edge as I described, developing a domed pocket containing talcum
from inside the inner tube.

And yet a well-applied patch snuggles right up to its inner tube.

It doesn't just sit there -- it appears to be firmly /pressed/ on,
despite no clamp or vise being used. And that's what piques my
curiosity.

Whatever simply sticks a patch onto a tube can be readily explained.
Heck, anyone can stick a Rice Crispy square onto an inner tube.

I'd just like to know what pushes or pulls a patch so securely
and firmly onto a tube. And I'm talking about naked tubes that
have been patched and then slung over the back of a chair overnight,
without being installed in a tire. That patch is on there like
a suction cup.


cheers,
Tom


tell us tom, how is it possible to read a perfectly well written post
with the adhesion mechanism clearly explained, but still fail tot
comprehend its contents. does it take practice? or do you have some
special training?

Still Just Me wrote:
On Sun, 26 Apr 2009 07:45:56 -0700, jim beam
wrote:

What's a suggested glue for tube on tube patching?
are you for real? how can you read a post that just tells you mechanism
and application, yet still utterly fail to comprehend what it means?
[rhetorical]


I'm looking for a brand name or two, Mr. personality, not a chemical
composition.

Perhaps if your primary mission wasn't to be the biggest asshole on
the Usenet, you might have detected that.



"hello, is this the psychic hotline? can you tell me what sjm actually
wants please? 'cos he's apparently incapable of stating anything so
simple. thanks for your help"

that's $2.99 per minute to you buddy.

In article ,
jim beam writes:
Tom Keats wrote:
In article ,
writes:
Michael Press wrote:

Now I'm wondering how those long polymers find their ways into
their holes or ruts or whatever allows them to interdigitate -- do
they just fall in when a hole opens up beneath them, or do they
just randomly flow around until they drop into a hole/rut/whatever?
If they're electrically drawn in, could that arguably be a chemical
process?
Physically it is similar to interleaving the pages of two books.
The force to pull them apart is enormous. It is not a chemical
process because chemical bonds are not changed. Very roughly, a
chemical bond changes when one or more electrons move permanently
from one orbit to another.
Vulcanizing rubber is a one way street chemically. Rubber is melted
with sulfur whence cross links form between polymers. This cross
linking cannot be undone to get back to the original constituents.
This sounds as though a REMA patch, once vulcanized, cannot be
removed. I find heating the patch on a flat surface (frying pan under
thumb pressure) to be an effective way of making well cured patches
removable. From all the chemistry in this thread, it seems my method
of applying the REMA patch, as soon as the vulcanizing fluid is no
^^^^^^^^^^^^^^^^^^^^^


In this discussion, some folks seem to refute that liquid vulcanizing
agents can coexist with rubber cement in the same off-the-shelf
container. There seems to be a lot of semantically induced confusion.

longer liquid, seems to be more conducive to polymerizing than waiting
for it to completely dry and before use, allowing patches to become
well adhered in several hours, seems also to be borne out.

In any event, having removed many leaky patches, that were ridden
immediately after patching, has shown me that they lift off, almost to
their edge as I described, developing a domed pocket containing talcum
from inside the inner tube.

And yet a well-applied patch snuggles right up to its inner tube.

It doesn't just sit there -- it appears to be firmly /pressed/ on,
despite no clamp or vise being used. And that's what piques my
curiosity.

Whatever simply sticks a patch onto a tube can be readily explained.
Heck, anyone can stick a Rice Crispy square onto an inner tube.

I'd just like to know what pushes or pulls a patch so securely
and firmly onto a tube. And I'm talking about naked tubes that
have been patched and then slung over the back of a chair overnight,
without being installed in a tire. That patch is on there like
a suction cup.


cheers,
Tom


tell us tom, how is it possible to read a perfectly well written post
with the adhesion mechanism clearly explained, but still fail tot
comprehend its contents. does it take practice? or do you have some
special training?

Stuff sticking to each other (adhesion) is one thing.

Stuff integrating itself with other stuff (cohesion)
is quite another. Non-chemical cohesion is a particularly
(sorry for the unintended pun) intriguing concept.


It would appear you resent people asking how or why.

It would appear you're axiomatically religous,
and resent inquiry.

That would make you an anti-scientist.

I dare you to consider that.

In the meantime, you're just another tiresome,
officious, bloody know-it-all with nothing of
value to contribute.

Or maybe you do have valuable stuff to contribute,
but you've obfiscated it with your snooty attitude.

So, where were we? Oh yeah. You were criticising
my communication capabilities. Yeah, I often leave
myself open to misconstruement. Oh well.



cheers,
Tom

--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca

In article ,
Phil W Lee phil(at)lee-family(dot)me(dot)uk writes:

We're being told one substance somehow molecularly
intimates and intermingles itself with another
similar substance, and yet the process is not
chemical.

Think of velcro, then reduce in scale to the molecular level.
The preparation with rubber cement can be visualised as the process
which makes the fibres on one side curl up into little hooks.

Aaah, I can visualize that.

Thank you.


cheers,
Tom

--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca

Still Just Me wrote, On 4/27/2009 12:47 PM:
On Sun, 26 Apr 2009 21:08:16 -0700, jim beam
wrote:


tell us tom, how is it possible to read a perfectly well written post
with the adhesion mechanism clearly explained, but still fail tot
comprehend its contents. does it take practice? or do you have some
special training?


First you tell us why you don't capitalize properly. It's a multiple
choice question. Possible answers:

a. too lazy
b. too stupid



c. shift-key failure?

--

Paul D Oosterhout
I work for SAIC (but I don't speak for SAIC)