Rubber cement question

On 2017-06-20 06:27, wrote:
On Tuesday, June 20, 2017 at 5:58:34 AM UTC-7, Jeff Liebermann
wrote:
On Tue, 20 Jun 2017 02:12:04 +0000 (UTC), David Scheidt
wrote:

In the case of the little tubes, the problem is not always that
the solvent has evaporated. The contents of tube can vulcanize
itself into a hard mass, even in the presence of solvent.
That's particularly likely where it's hot, and the vulcanizing
fluid is kept somehwerer like a seat wedge, where it's well
heated.

I keep both automobile and bicycle tire patch kits in my car. It
gets rather warm in the car at times. Both kits include those
little tubes of rubber cement. At best, they last a few months. I
tore apart one that was in my rather hot car for over one year. It
was almost completely empty with only a tiny rubber-like blob at
the bottom of the tube. It had never been opened and was not
punctured or leaking. At first, I thought it might be defective
from the factory, but then I found another tube with the same
problem. I've gone no further with this investigation. If it's
heat that's causing the cement to harden, then storing it in a car
or riding around with it on a bicycle, are not going to work.

Except for it being banned in California for using MEK and toluene
as the solvent, I wonder if this stuff might work better?
https://www.ellsworth.com/products/by-manufacturer/3m/adhesives/solvent-based/3m-scotch-weld-1300-neoprene-rubber-and-gasket-adhesive-yellow-5-oz-tube/


Bicycle tires are mostly butyl rubber.

What ever the solvent is, that is the carrier, doesn't "dry up".
Eventually it leaks out through the crimped end of the tube. I
haven't had a problem with glass bottles though I would imagine in
enough heat the solvent could gasify enough to leak out of just about
everything. Just how good is the cap seal?

The larger the tube usually the smaller the ratio of solvent and the
longer it will last.

I ordered an entire load of patch kits from ProPatch a couple of
years ago to sell cheaply to the group I ride with. No one bought one
kit at a buck. The patch kits are small. So far they do not appear to
dry up meaning that the crimped section of tube is managed in such a
manner that it doesn't leak. Once opened the glue appears to dry up
as rapidly as any other Rema glue.


One lone buck and they didn't buy? They must all be cheapskates. Where
do you get such cheap patch kits? The ones out here are around $3 and do
not last long (well, the cement doesn't).


Also there is the consideration that glueless patches do exist but
I've only used them enough to gain confidence that they indeed do
work though you have to be very careful in the tube preparation.


Most riders told me that glueless patches are meant to get you home, not
as a permanent fix.

--
Regards, Joerg

http://www.analogconsultants.com/

On Tuesday, June 20, 2017 at 10:50:31 AM UTC-7, David Scheidt wrote:
Frank Krygowski wrote:
:On 6/20/2017 9:27 AM, wrote:
: On Tuesday, June 20, 2017 at 5:58:34 AM UTC-7, Jeff Liebermann wrote:
: On Tue, 20 Jun 2017 02:12:04 +0000 (UTC), David Scheidt
: wrote:
:
: In the case of the little tubes, the problem is not always that the
: solvent has evaporated. The contents of tube can vulcanize itself
: into a hard mass, even in the presence of solvent. That's
: particularly likely where it's hot, and the vulcanizing fluid is kept
: somehwerer like a seat wedge, where it's well heated.
:
: I keep both automobile and bicycle tire patch kits in my car. It gets
: rather warm in the car at times. Both kits include those little tubes
: of rubber cement. At best, they last a few months. I tore apart one
: that was in my rather hot car for over one year. It was almost
: completely empty with only a tiny rubber-like blob at the bottom of
: the tube. It had never been opened and was not punctured or leaking.
: At first, I thought it might be defective from the factory, but then I
: found another tube with the same problem. I've gone no further with
: this investigation. If it's heat that's causing the cement to harden,
: then storing it in a car or riding around with it on a bicycle, are
: not going to work.
:
: Except for it being banned in California for using MEK and toluene as
: the solvent, I wonder if this stuff might work better?
: https://www.ellsworth.com/products/by-manufacturer/3m/adhesives/solvent-based/3m-scotch-weld-1300-neoprene-rubber-and-gasket-adhesive-yellow-5-oz-tube/
: Bicycle tires are mostly butyl rubber.
:
: What ever the solvent is, that is the carrier, doesn't "dry up". Eventually it leaks out through the crimped end of the tube.

:I wondered about that, and whether some more enthusiastic crimping would
:help, using a bench vise.

When the tubes were made of lead foil, it might have. They're now
some sort of laminated plastic material that's closed by
(heat|ultrasonic) welding.

:But to me the problem seems small. Patch kits are cheap.

they're cheap, but when you need one, it would be nice if the one in
your bag worked.

Since I have Rema (Made in USA) and ProPatch (Made in Taiwan) right here I looked at them. Both tubes are metal. One difference is that the Rema has a number of some sort (perhaps a batch no.) stamped into the fold which could possibly interfere with the seal.

But as a rule I have only had Rema go dead on me and then only after a very long time. But both dry up fairly rapidly after puncturing the seal and using them just once.

On Tuesday, June 20, 2017 at 1:01:13 PM UTC-7, Joerg wrote:
On 2017-06-20 06:27, wrote:
On Tuesday, June 20, 2017 at 5:58:34 AM UTC-7, Jeff Liebermann
wrote:
On Tue, 20 Jun 2017 02:12:04 +0000 (UTC), David Scheidt
wrote:

In the case of the little tubes, the problem is not always that
the solvent has evaporated. The contents of tube can vulcanize
itself into a hard mass, even in the presence of solvent.
That's particularly likely where it's hot, and the vulcanizing
fluid is kept somehwerer like a seat wedge, where it's well
heated.

I keep both automobile and bicycle tire patch kits in my car. It
gets rather warm in the car at times. Both kits include those
little tubes of rubber cement. At best, they last a few months. I
tore apart one that was in my rather hot car for over one year. It
was almost completely empty with only a tiny rubber-like blob at
the bottom of the tube. It had never been opened and was not
punctured or leaking. At first, I thought it might be defective
from the factory, but then I found another tube with the same
problem. I've gone no further with this investigation. If it's
heat that's causing the cement to harden, then storing it in a car
or riding around with it on a bicycle, are not going to work.

Except for it being banned in California for using MEK and toluene
as the solvent, I wonder if this stuff might work better?
https://www.ellsworth.com/products/by-manufacturer/3m/adhesives/solvent-based/3m-scotch-weld-1300-neoprene-rubber-and-gasket-adhesive-yellow-5-oz-tube/


Bicycle tires are mostly butyl rubber.

What ever the solvent is, that is the carrier, doesn't "dry up".
Eventually it leaks out through the crimped end of the tube. I
haven't had a problem with glass bottles though I would imagine in
enough heat the solvent could gasify enough to leak out of just about
everything. Just how good is the cap seal?

The larger the tube usually the smaller the ratio of solvent and the
longer it will last.

I ordered an entire load of patch kits from ProPatch a couple of
years ago to sell cheaply to the group I ride with. No one bought one
kit at a buck. The patch kits are small. So far they do not appear to
dry up meaning that the crimped section of tube is managed in such a
manner that it doesn't leak. Once opened the glue appears to dry up
as rapidly as any other Rema glue.


One lone buck and they didn't buy? They must all be cheapskates. Where
do you get such cheap patch kits? The ones out here are around $3 and do
not last long (well, the cement doesn't).


Also there is the consideration that glueless patches do exist but
I've only used them enough to gain confidence that they indeed do
work though you have to be very careful in the tube preparation.


Most riders told me that glueless patches are meant to get you home, not
as a permanent fix.

I bought a case of 200 so they only cost me $0.50 apiece.

If you carefully sand the area around the puncture, place the glueless patch, put the tube in the tire and fill it to pressure when you get home and try to remove the patch it's as solid as any normal patch.

What I saw was people trying to stick a glueless patch on unprepared tubes and then complaining that they were junk when they tried to fill the tube.

On 2017-06-20 13:19, wrote:
On Tuesday, June 20, 2017 at 1:01:13 PM UTC-7, Joerg wrote:
On 2017-06-20 06:27, wrote:
On Tuesday, June 20, 2017 at 5:58:34 AM UTC-7, Jeff Liebermann
wrote:
On Tue, 20 Jun 2017 02:12:04 +0000 (UTC), David Scheidt
wrote:

In the case of the little tubes, the problem is not always
that the solvent has evaporated. The contents of tube can
vulcanize itself into a hard mass, even in the presence of
solvent. That's particularly likely where it's hot, and the
vulcanizing fluid is kept somehwerer like a seat wedge, where
it's well heated.

I keep both automobile and bicycle tire patch kits in my car.
It gets rather warm in the car at times. Both kits include
those little tubes of rubber cement. At best, they last a few
months. I tore apart one that was in my rather hot car for
over one year. It was almost completely empty with only a tiny
rubber-like blob at the bottom of the tube. It had never been
opened and was not punctured or leaking. At first, I thought it
might be defective from the factory, but then I found another
tube with the same problem. I've gone no further with this
investigation. If it's heat that's causing the cement to
harden, then storing it in a car or riding around with it on a
bicycle, are not going to work.

Except for it being banned in California for using MEK and
toluene as the solvent, I wonder if this stuff might work
better?
https://www.ellsworth.com/products/by-manufacturer/3m/adhesives/solvent-based/3m-scotch-weld-1300-neoprene-rubber-and-gasket-adhesive-yellow-5-oz-tube/




Bicycle tires are mostly butyl rubber.

What ever the solvent is, that is the carrier, doesn't "dry up".
Eventually it leaks out through the crimped end of the tube. I
haven't had a problem with glass bottles though I would imagine
in enough heat the solvent could gasify enough to leak out of
just about everything. Just how good is the cap seal?

The larger the tube usually the smaller the ratio of solvent and
the longer it will last.

I ordered an entire load of patch kits from ProPatch a couple of
years ago to sell cheaply to the group I ride with. No one bought
one kit at a buck. The patch kits are small. So far they do not
appear to dry up meaning that the crimped section of tube is
managed in such a manner that it doesn't leak. Once opened the
glue appears to dry up as rapidly as any other Rema glue.


One lone buck and they didn't buy? They must all be cheapskates.
Where do you get such cheap patch kits? The ones out here are
around $3 and do not last long (well, the cement doesn't).


Also there is the consideration that glueless patches do exist
but I've only used them enough to gain confidence that they
indeed do work though you have to be very careful in the tube
preparation.


Most riders told me that glueless patches are meant to get you
home, not as a permanent fix.

I bought a case of 200 so they only cost me $0.50 apiece.


What brand and where did you buy?


If you carefully sand the area around the puncture, place the
glueless patch, put the tube in the tire and fill it to pressure when
you get home and try to remove the patch it's as solid as any normal
patch.

What I saw was people trying to stick a glueless patch on unprepared
tubes and then complaining that they were junk when they tried to
fill the tube.


Ok, but the normal process requires vulcanizing the sanded tube portion.
This is done by applying the cement and then letting it dry. The folks
who wrote the instructions for Slime 1050 seem to have forgotten (!)
that important part of letting things dry. How is that going to work
with a glueless patch?

--
Regards, Joerg

http://www.analogconsultants.com/

On Tuesday, June 20, 2017 at 1:50:31 PM UTC-4, David Scheidt wrote:
Frank Krygowski wrote:
:On 6/20/2017 9:27 AM, wrote:
: On Tuesday, June 20, 2017 at 5:58:34 AM UTC-7, Jeff Liebermann wrote:
: On Tue, 20 Jun 2017 02:12:04 +0000 (UTC), David Scheidt
: wrote:
:
: In the case of the little tubes, the problem is not always that the
: solvent has evaporated. The contents of tube can vulcanize itself
: into a hard mass, even in the presence of solvent. That's
: particularly likely where it's hot, and the vulcanizing fluid is kept
: somehwerer like a seat wedge, where it's well heated.
:
: I keep both automobile and bicycle tire patch kits in my car. It gets
: rather warm in the car at times. Both kits include those little tubes
: of rubber cement. At best, they last a few months. I tore apart one
: that was in my rather hot car for over one year. It was almost
: completely empty with only a tiny rubber-like blob at the bottom of
: the tube. It had never been opened and was not punctured or leaking.
: At first, I thought it might be defective from the factory, but then I
: found another tube with the same problem. I've gone no further with
: this investigation. If it's heat that's causing the cement to harden,
: then storing it in a car or riding around with it on a bicycle, are
: not going to work.
:
: Except for it being banned in California for using MEK and toluene as
: the solvent, I wonder if this stuff might work better?
: https://www.ellsworth.com/products/by-manufacturer/3m/adhesives/solvent-based/3m-scotch-weld-1300-neoprene-rubber-and-gasket-adhesive-yellow-5-oz-tube/
: Bicycle tires are mostly butyl rubber.
:
: What ever the solvent is, that is the carrier, doesn't "dry up". Eventually it leaks out through the crimped end of the tube.

:I wondered about that, and whether some more enthusiastic crimping would
:help, using a bench vise.

When the tubes were made of lead foil, it might have. They're now
some sort of laminated plastic material that's closed by
(heat|ultrasonic) welding.

:But to me the problem seems small. Patch kits are cheap.

they're cheap, but when you need one, it would be nice if the one in
your bag worked.

--
sig 118

That's precisely why I check my tube of glue BEFORE I go on a longer ride. It's part of my Pre-Ride checklist. I'd rather discover a problem here at home than many many kilometers out on a ride whether the problem be repair equipment or something on the bicycle.

Cheers

Cheers

SR's glue check...

Opening tube shortens tube life

Try comparing

On Tue, 20 Jun 2017 12:53:44 -0700, Joerg
wrote:

On 2017-06-19 18:17, Jeff Liebermann wrote:
On Mon, 19 Jun 2017 12:47:56 -0700, Joerg
wrote:

Question: Is there some sort of cheap/free micro container
that could be used to fill some into and carry along? Something where it
lasts a longer time than the tiny tubes but where it's ok that the goop
in this little container is for use at one event only.

Aluminum pill bottles perhaps?
https://www.google.com/search?q=aluminum+pill+bottles&tbm=isch
I have a similar problem with Nitrostat pill evaporating into
uselessness. I drilled one and inserted a tire stem and valve. It
holds pressure quite nicely. The idea is to pressurize the pill
bottle to something higher than the vapor pressure for nitroglycerin
so that it will not voltatize. I suspect the same can be done for
rubber cement by pressuring with something that is not very reactive,
such as CO2, N2, or perhaps propane. Some kind of anti-sieze or
grease might be needed to keep the threads from being glued in place.
The bottle I have here has only 3 threads and is rather loose, but has
a nice o-ring to seal the cap.

Disclaimer: I haven't tried this with rubber cement.

Good idea.

Not so good idea. See message by Radey Shouman for why gas
pressurizing won't reduce evaporation.

It looks like they have an o-ring to seal. I could try to
fill one to the brim. From beer brewing I'd theoretically have access to
the CO2 that escapes the fermenter but pressurizing with that would be a
challenge. I'd have to suck the CO2 into an old bicycle pump and then
somehow fill that in.

That should work, but instead of a small volume, high pressure bicycle
pump, perhaps a large volume, low pressure air mattress or inflatable
toy hand pumb might be better.

I still think the pill bottles will work, or maybe a glass vial.
However, some other scheme for reducing or eliminating the air space
under the cap will need to be contrived. Right now (5AM), I'm
thinking of a PTFE plug and a spring under the cap end of the pill
bottle.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann wrote:
:On Tue, 20 Jun 2017 02:12:04 +0000 (UTC), David Scheidt
wrote:

:In the case of the little tubes, the problem is not always that the
:solvent has evaporated. The contents of tube can vulcanize itself
:into a hard mass, even in the presence of solvent. That's
:particularly likely where it's hot, and the vulcanizing fluid is kept
:somehwerer like a seat wedge, where it's well heated.

:I keep both automobile and bicycle tire patch kits in my car. It gets
:rather warm in the car at times. Both kits include those little tubes
f rubber cement. At best, they last a few months. I tore apart one
:that was in my rather hot car for over one year. It was almost
:completely empty with only a tiny rubber-like blob at the bottom of
:the tube. It had never been opened and was not punctured or leaking.
:At first, I thought it might be defective from the factory, but then I
:found another tube with the same problem. I've gone no further with
:this investigation. If it's heat that's causing the cement to harden,
:then storing it in a car or riding around with it on a bicycle, are
:not going to work.

It occurs to me that it might be getting hot enough to boil the
solvent. That would increase the pressure in the tube, and ight be
enough to force open a seal. The increased vapor pressure of less
than boiling might be able to do the same thing. That would explain
why people like me and Frank, who live in more temperate climates
don't have the problem much.

:Except for it being banned in California for using MEK and toluene as
:the solvent, I wonder if this stuff might work better?
:https://www.ellsworth.com/products/by-manufacturer/3m/adhesives/solvent-based/3m-scotch-weld-1300-neoprene-rubber-and-gasket-adhesive-yellow-5-oz-tube/
:Bicycle tires are mostly butyl rubber.

IT would work, but not as well as vulcanizing fluid. The tube contact
portion of the patch is made of unvulcanized rubber, with a zinc
ultra-accelerator mixed in. The vulcanizing fluid contains an
accelerator that acts as a an activator for the ultra-acclerator.
Without that, you just have glue. the tube-patch interface is subject
ot lots of force, and glues have a hard time with it.


--
sig 102

On 21-06-17 03:26, Sir Ridesalot wrote:
That's precisely why I check my tube of glue BEFORE I go on a longer ride. It's part of my Pre-Ride checklist. I'd rather discover a problem here at home than many many kilometers out on a ride whether the problem be repair equipment or something on the bicycle.

I carry a spare (inner) tube as well as a patch kit. If it's just one
flat then I change the tube and patch at leisure when I'm back home.
Also good in the case of a flat that destroys the tube such as I had
years ago (https://flic.kr/p/9XmmWn ), although I'm pretty sure I now
know how to avoid such a thing by braking more carefully.

Ned

On 2017-06-21 05:08, Jeff Liebermann wrote:
On Tue, 20 Jun 2017 12:53:44 -0700, Joerg
wrote:

On 2017-06-19 18:17, Jeff Liebermann wrote:
On Mon, 19 Jun 2017 12:47:56 -0700, Joerg
wrote:

Question: Is there some sort of cheap/free micro container
that could be used to fill some into and carry along? Something where it
lasts a longer time than the tiny tubes but where it's ok that the goop
in this little container is for use at one event only.

Aluminum pill bottles perhaps?
https://www.google.com/search?q=aluminum+pill+bottles&tbm=isch
I have a similar problem with Nitrostat pill evaporating into
uselessness. I drilled one and inserted a tire stem and valve. It
holds pressure quite nicely. The idea is to pressurize the pill
bottle to something higher than the vapor pressure for nitroglycerin
so that it will not voltatize. I suspect the same can be done for
rubber cement by pressuring with something that is not very reactive,
such as CO2, N2, or perhaps propane. Some kind of anti-sieze or
grease might be needed to keep the threads from being glued in place.
The bottle I have here has only 3 threads and is rather loose, but has
a nice o-ring to seal the cap.

Disclaimer: I haven't tried this with rubber cement.

Good idea.

Not so good idea. See message by Radey Shouman for why gas
pressurizing won't reduce evaporation.

It looks like they have an o-ring to seal. I could try to
fill one to the brim. From beer brewing I'd theoretically have access to
the CO2 that escapes the fermenter but pressurizing with that would be a
challenge. I'd have to suck the CO2 into an old bicycle pump and then
somehow fill that in.

That should work, but instead of a small volume, high pressure bicycle
pump, perhaps a large volume, low pressure air mattress or inflatable
toy hand pumb might be better.

I still think the pill bottles will work, or maybe a glass vial.
However, some other scheme for reducing or eliminating the air space
under the cap will need to be contrived. Right now (5AM), I'm
thinking of a PTFE plug and a spring under the cap end of the pill
bottle.


If the micro-pill-bottle had a milled lid that would protrude into the
rubber cement when filled to the brim there should be rubber cement
oozing out during the closing process. That ought to drive out any air
inside. Or at least almost all of it.

It would be ok to have to refill this every three months or so. As
someone wrote, li'l rubber cement tubes are cheap enough but you can't
buy 20 of them, put them on a shelf, grab one every three month and
expect them to still be ok after the summer. Because often they aren't.

Maybe one could buy 20 rubber cement tubes, store them in the freezer
and then take a fresh one every few months?

--
Regards, Joerg

http://www.analogconsultants.com/