Stronger rubber cement?

On 2017-01-03 18:47, David Scheidt wrote:
John B. wrote:
:On Tue, 03 Jan 2017 17:04:40 -0800, Joerg
:wrote:

:Gentlemen,
:
:Is there something stronger than the usual rubber cement in the patch
:kits? Ideally something that won't dry out so fast or where multiple
:cheap small tubes are available.
:
:The reason is that I sometimes have larger holes from side wall
:blow-outs. Not inch-long gashes but one or two tenths of an inch long.
:The tubes I use are super thick and, therefore, expensive. $15-20 each
:and that's not something to be thrown out lightly. Instead of the li'l
:REMA patches I need to use thicker rubber from an older sacrified tube
:but this has to be vulcanized/cemented really well.

:My LBS usually has small sealed tubes of glue. When I see them I buy
:four or five and when I open a sealed tube, in the kit on the bike, I
:replace it with another sealed one as find the glue has dried up is
:not quite so much of a catastrophe at home :-)

:Or you might try contact cement what I suspect is what is in the usual
:tire patching kit.

:By the way, "vulcanizing" implies the use of heat, and sulphur, and I

Vulcanizing may have the connotation of involving heat, but it's a chemical
reaction, which results in the sulphur in the rubber becoming
crosslinked.


That's how I also remember it.


... Patches, at least the good ones such as Rema and park,
are a multi-layered assembly. The top layers are for strength, the
bottom (closest to the tube) consists of unvulcanized rubber, mixed
with a vulcanizing ultra-accelerator (there are a number of zinc
thiols that are suitable, which ones are used are trade secrets. ZDDP
is typical, though). vulcanizing cement consists of a unvulcanized
rubber particles, a solvent to carry them, and a vulcanizing
activator. Cyclohexylamine is common, but there are others that will
work, and are less toxic. The activator reacts with the zinc thiol,
and causes the patch, the rubber in the cement, and the surface of
tube to become vulcanized. There's not much free sulphur in the tube,
because it's vulcanized, which is one of the reasons that it's
important to properly scarify the tube surface before patching; it
greatly increases the surface area of the patch. The reaction is not
instant, but it happens pretty fast at room temperature, and
continues for some time, until all the sulphur available has linke.d


Ever since I began using REMA patches and the cement that comes with
them my result were less stellar than in Europe with the classic kits.
Those contain much thicker patches that looked like round chunks of
tube, sometimes slightly beveled. Can't find those here in the US.

Currently I have two tubes of the thick expensive kinds where REMA
patches partially came off after test-inflating outside the tire.
Despite being very diligent with sanding and applying.


The accelerator in the cement is one reason that tubes of glue
sometimes are just rubber, and not cement.


The question is why would be the good ones to buy?

I am usually only doing tube repairs at home, carrying thinner spare
tubes for the road. Except when helping other riders which is the only
reason I even carry a patch kit.

--
Regards, Joerg

http://www.analogconsultants.com/

On 2017-01-03 17:13, DATAKOLL MARINE RESEARCH wrote:
try DT or Specialized.

or for example

https://www.google.com/#q=rubber+con...ement&tbm=shop

contact cement not rubber adhesive.

Henkel-Loctite has one last I looked.

Weldwood red is super contact cement but its a liquid not thickened liquid like Weldwood in the glass bottle which is OK.


Thanks, I'll have to look into that. I read that contact cement doesn't
make for a pliable connection which is required on the side walls. Maybe
the people trying and reporting it on the web did something wrong though.

--
Regards, Joerg

http://www.analogconsultants.com/

On 2017-01-04 00:01, Dennis Davis wrote:
In article ,
Joerg wrote:
Gentlemen,

Is there something stronger than the usual rubber cement in the
patch kits? Ideally something that won't dry out so fast or where
multiple cheap small tubes are available.

The reason is that I sometimes have larger holes from side wall
blow-outs. Not inch-long gashes but one or two tenths of an
inch long. The tubes I use are super thick and, therefore,
expensive. $15-20 each and that's not something to be thrown
out lightly. Instead of the li'l REMA patches I need to use
thicker rubber from an older sacrified tube but this has to be
vulcanized/cemented really well.

The small REMA patches are some 15mm in diameter. Larger sizes
exist. I believe the next size up is 25mm in diameter and the oval
REMA patches are available. An ebay search should throw up what's
available by mail order.

Same for the the REMA rubber cement. It comes in different size
tubes, including the small ones you mention. Again an Internet
search should show what's available.

I don't usually have problems using REMA patches & glue. However
puncture repairing technique can be as contentious as chain cleaning
and lubrication advice. I'm going to keep my head down :-)


I have used the big oblong REMAs as well and that's the ones thah failed
the most on sidewalls. They are rather thin.

--
Regards, Joerg

http://www.analogconsultants.com/

On 2017-01-03 20:23, Jeff Liebermann wrote:
On Tue, 03 Jan 2017 17:04:40 -0800, Joerg
wrote:

Is there something stronger than the usual rubber cement in the patch
kits? Ideally something that won't dry out so fast or where multiple
cheap small tubes are available.

Contact cement. It's a neoprene rubber based goo that remains fairly
flexible if applied in a very thin layer. Smear some on both the tire
and the patch, let air dry for at least 10 minutes (longer is better),
and stick together with a little compression pressure. I've used a
roller, two blocks of wood and a C-clamp, and beating on the sandwich
with a hammer. They all work.

Rubber cement is a latex rubber based goo. Otherwise, it's similar to
contact cement. It also uses many of the same solvents as contact
cement. Bicycle patches use heptane, naphtha, or a mixture of both.
Rubber and contact cement use these or other organic solvents. There's
also a water based version of rubber cement.

Contact cement solvents won't evaporate as fast as rubber cement
because the contact cement is thicker in the bottle and forms an
effective barrier. However, the solvents will rapidly evaporate if
the can, bottle, or tube is left in the sun.

Contact cement on bicycle tubes is nothing new:
http://www.bicitoro.com/how-to-glue-inner-tubes/
However, if do some Googling, you'll probably find testimonials from
people trying contact cement, and claiming it doesn't work. The
problem is that while rubber cement vulcanizing patches require
cleaning and sanding before applying, some people seem to forget to do
these things when using contact cement.

I've also tried glue used for patching my wet suit:
https://www.walmart.com/ip/Mcnett-14114-Seal-Cement-2-Oz-Tube-Black/21970283
https://www.youtube.com/watch?v=q9QK0yF540c
https://www.google.com/search?q=neoprene+wetsuit+glue&tbm=isch
http://www.bodylinewetsuits.co.uk/2015/01/12/using-black-witch-neoprene-glue/
I've only done one tire with wet suit glue and found that it didn't
last. However, that was in a rush, with little preparation, no
clamping, and I used a piece of vinyl for the patch. I suspect I can
improve the bond if I were more organized and careful.

The reason is that I sometimes have larger holes from side wall
blow-outs. Not inch-long gashes but one or two tenths of an inch long.
The tubes I use are super thick and, therefore, expensive. $15-20 each
and that's not something to be thrown out lightly. Instead of the li'l
REMA patches I need to use thicker rubber from an older sacrified tube
but this has to be vulcanized/cemented really well.

Hmmm... contact cement is more expensive than rubber cement. If I had
to find something cheaper than rubber cement, methinks RTV (room
temperature vulcanizing rubber) would probably qualify. The catch is
that you might have to wait overnight for the RTV to harden.

Anyway, I suggest you sacrifice an old tube, cut it apart, cut some
slits, patch with the various available glues, and test the results
with a pull test, peel test, pressure test, and flexibility test.


I'll look into contact cement. Gene also suggested that. Cost is not so
much an issue but shelf life after opening is. The usual rubber cement
is toast only a few months after opening.

It also has to become a pliable connection because those cuts are on the
side walls. Ever since moving to tire liners plus thich tubes plus thick
tire surfaces I don't get "regular" flats via running surface punctures
anymore.

--
Regards, Joerg

http://www.analogconsultants.com/

On 2017-01-04 01:19, Tosspot wrote:
On 04/01/17 01:04, Joerg wrote:
Gentlemen,

Is there something stronger than the usual rubber cement in the patch
kits? Ideally something that won't dry out so fast or where multiple
cheap small tubes are available.

The reason is that I sometimes have larger holes from side wall
blow-outs. Not inch-long gashes but one or two tenths of an inch long.
The tubes I use are super thick and, therefore, expensive. $15-20 each
and that's not something to be thrown out lightly. Instead of the li'l
REMA patches I need to use thicker rubber from an older sacrified tube
but this has to be vulcanized/cemented really well.

UK, but must be available all over

http://www.tyre-equipment.co.uk/acat...r-Patches.html


Go up to 180mmx95mm and are less than a UKP per patch.


Thanks! Time for a trip to the autoparts store since there is

http://www.vipal-usa.com/repair_line_e.html

Looks like a Brazilian company.


The 30mm patches are 13 squids per 100! Surely, surely even Joerg can't
get through that amount that fast!


I hardly get flats but when I do they are hardcore. Typically caused by
those notorious #%&^!! flimsy side walls of bicycle tires. Which is also
why I am always on the lookout for tires with better side walls. For the
MTB I found that Asian ones do better in that domain but haven't found
any yet for the road bike. Will try CST, their Conquistare tires look
promising but I could not find reviews.

Heavier tires are generally better and finally those appeared for 29".
For 700c it's still slim pickens.

--
Regards, Joerg

http://www.analogconsultants.com/

On 2017-01-04 06:26, wrote:
On Tuesday, January 3, 2017 at 5:04:38 PM UTC-8, Joerg wrote:
Gentlemen,

Is there something stronger than the usual rubber cement in the
patch kits? Ideally something that won't dry out so fast or where
multiple cheap small tubes are available.

The reason is that I sometimes have larger holes from side wall
blow-outs. Not inch-long gashes but one or two tenths of an inch
long. The tubes I use are super thick and, therefore, expensive.
$15-20 each and that's not something to be thrown out lightly.
Instead of the li'l REMA patches I need to use thicker rubber from
an older sacrified tube but this has to be vulcanized/cemented
really well.

-- Regards, Joerg

http://www.analogconsultants.com/

Jeorg, considering the amount and extent of flats that you get
perhaps you should observe Tosspot's recommendations:

http://www.tyre-equipment.co.uk/acat...-PSF_Plus.html


:-)

I don't get many flats but if I do they are nasty tears on the sides
where tubes flex all the time. Caused by side wall failures of tires.

So I need something that is super strong in the vulcanizing process and
where the tube or can contents won't dry out after just a few months of
storage. I always fix at home so cold storage and the necessity to use
pressure tools and such would be no problem.

--
Regards, Joerg

http://www.analogconsultants.com/

Joerg wrote:
:On 2017-01-04 00:01, Dennis Davis wrote:
: In article ,
: Joerg wrote:
: Gentlemen,
:
: Is there something stronger than the usual rubber cement in the
: patch kits? Ideally something that won't dry out so fast or where
: multiple cheap small tubes are available.
:
: The reason is that I sometimes have larger holes from side wall
: blow-outs. Not inch-long gashes but one or two tenths of an
: inch long. The tubes I use are super thick and, therefore,
: expensive. $15-20 each and that's not something to be thrown
: out lightly. Instead of the li'l REMA patches I need to use
: thicker rubber from an older sacrified tube but this has to be
: vulcanized/cemented really well.
:
: The small REMA patches are some 15mm in diameter. Larger sizes
: exist. I believe the next size up is 25mm in diameter and the oval
: REMA patches are available. An ebay search should throw up what's
: available by mail order.
:
: Same for the the REMA rubber cement. It comes in different size
: tubes, including the small ones you mention. Again an Internet
: search should show what's available.
:
: I don't usually have problems using REMA patches & glue. However
: puncture repairing technique can be as contentious as chain cleaning
: and lubrication advice. I'm going to keep my head down :-)
:

:I have used the big oblong REMAs as well and that's the ones thah failed
:the most on sidewalls. They are rather thin.

Use a tire patch or boot, not one for an inner tube. Totally
different problems, totally different solutions.


--
sig 117

On Wednesday, January 4, 2017 at 7:41:16 AM UTC-8, Joerg wrote:
On 2017-01-04 06:26, wrote:
On Tuesday, January 3, 2017 at 5:04:38 PM UTC-8, Joerg wrote:
Gentlemen,

Is there something stronger than the usual rubber cement in the
patch kits? Ideally something that won't dry out so fast or where
multiple cheap small tubes are available.

The reason is that I sometimes have larger holes from side wall
blow-outs. Not inch-long gashes but one or two tenths of an inch
long. The tubes I use are super thick and, therefore, expensive.
$15-20 each and that's not something to be thrown out lightly.
Instead of the li'l REMA patches I need to use thicker rubber from
an older sacrified tube but this has to be vulcanized/cemented
really well.

-- Regards, Joerg

http://www.analogconsultants.com/

Jeorg, considering the amount and extent of flats that you get
perhaps you should observe Tosspot's recommendations:

http://www.tyre-equipment.co.uk/acat...-PSF_Plus.html


:-)

I don't get many flats but if I do they are nasty tears on the sides
where tubes flex all the time. Caused by side wall failures of tires.

So I need something that is super strong in the vulcanizing process and
where the tube or can contents won't dry out after just a few months of
storage. I always fix at home so cold storage and the necessity to use
pressure tools and such would be no problem.

--
Regards, Joerg

http://www.analogconsultants.com/

Considering that you get sidewall failures you should probably only use tires that have bead to bead belts and also high thread-count cords. Doing so would give you a dramatic drop in the failures. If you're getting failures of Gatorskins that must be some sort of terrain you commute on.

Joerg wrote:

:I'll look into contact cement. Gene also suggested that. Cost is not so
:much an issue but shelf life after opening is. The usual rubber cement
:is toast only a few months after opening.

Go to your local auto parts store. Buy a can of vulcanizing fluid.
It'll come with a brush in the lid. The can in my desk at work has
been open and used for five years. Still good.

--
There's nothing sadder than an ontologist without an ontogenesis.
-- some guy with a beard

On 1/4/2017 10:17 AM, Joerg wrote:

Ever since I began using REMA patches and the cement that comes with
them my result were less stellar than in Europe with the classic kits.
Those contain much thicker patches that looked like round chunks of
tube, sometimes slightly beveled. Can't find those here in the US.

Currently I have two tubes of the thick expensive kinds where REMA
patches partially came off after test-inflating outside the tire.
Despite being very diligent with sanding and applying.

I don't see any value to test inflating a freshly patched tube outside
the tire. You're imparting stresses that the patch-to-tube bond will
never see in its normal working life, and it will be difficult for that
immature bond to resist them.

Patches that have completely cured stand up to being inflate outside the
tire, in my experience. I've never had one fail.

--
- Frank Krygowski