Slime rubber cement, let dry or not?

Got a tear in a thick tube, possibly a production defect. Upon hints
from this NG I bought Slime Rubber Cement a couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552

The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose particles and making
sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put the patch
into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with letting it dry
first resulted in the patch literally falling off. So it does not seem
to be the same stuff that's in the little patch kit tubes.

--
Regards, Joerg

http://www.analogconsultants.com/

On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse
than other rubber patching products.

That said, some old guys in the motorcycle/auto tire
business would do that- scuff, blow clean with compressed
air and then wet the area liberally with rubber cement.
After a couple of minutes' wait, he would draw a blade
across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface.
Slap patch on and press well with a patch stitcher[1] and
you're golden.

When I was young, patching tubes was all day every day
(labor was cheap, tubes were expensive) and we used the Tech
brand patching system. Scrub area clean with Tech Buffer
(mostly trichlorethylene) on a clean cloth which removes a
striking amount of black scum. Then just wet an area
slightly larger than the patch- not drippy or gloppy, just
enough to wet the area. It will look dry in well under a
minute. Press down patch and stitch it home. I had a
failure or two in a year doing a couple dozen a day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get
the area clean and you're well on your way to a successful
patch.
#2 by frequency is slapping a patch over wet cement. That
makes the patch deform with wrinkles, which leak. Customers
bring those in (I bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide
outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On 2020-04-30 13:35, AMuzi wrote:
On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse than other
rubber patching products.

That said, some old guys in the motorcycle/auto tire business would do
that- scuff, blow clean with compressed air and then wet the area
liberally with rubber cement. After a couple of minutes' wait, he would
draw a blade across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface. Slap patch on
and press well with a patch stitcher[1] and you're golden.


That's what I just did with two patches. One was a hole, the other a
defect that could have torn later.

I didn't have tri but used an old washed T-shirt.

Knocking on wood ...


When I was young, patching tubes was all day every day (labor was cheap,
tubes were expensive) and we used the Tech brand patching system. Scrub
area clean with Tech Buffer (mostly trichlorethylene) on a clean cloth
which removes a striking amount of black scum. Then just wet an area
slightly larger than the patch- not drippy or gloppy, just enough to wet
the area. It will look dry in well under a minute. Press down patch and
stitch it home. I had a failure or two in a year doing a couple dozen a
day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get the area clean
and you're well on your way to a successful patch.
#2 by frequency is slapping a patch over wet cement. That makes the
patch deform with wrinkles, which leak. Customers bring those in (I
bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg


Thanks for the good hints, Andrew. I had to fix a thin tube, found the
thorn-resistant tube to be beyond repair, it started ripping along a
factory seam. I'll start another thread, maybe someone knows a better
version.

--
Regards, Joerg

http://www.analogconsultants.com/

On 4/30/2020 4:35 PM, AMuzi wrote:
On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse than other
rubber patching products.

That said, some old guys in the motorcycle/auto tire business would do
that- scuff, blow clean with compressed air and then wet the area
liberally with rubber cement. After a couple of minutes' wait, he would
draw a blade across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface. Slap patch on
and press well with a patch stitcher[1] and you're golden.

When I was young, patching tubes was all day every day (labor was cheap,
tubes were expensive) and we used the Tech brand patching system.* Scrub
area clean with Tech Buffer (mostly trichlorethylene) on a clean cloth
which removes a striking amount of black scum.* Then just wet an area
slightly larger than the patch- not drippy or gloppy, just enough to wet
the area. It will look dry in well under a minute.* Press down patch and
stitch it home. I had a failure or two in a year doing a couple dozen a
day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get the area clean
and you're well on your way to a successful patch.
#2 by frequency is slapping a patch over wet cement. That makes the
patch deform with wrinkles, which leak. Customers bring those in (I
bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg

The patch stitcher looks remarkably similar to a window screen spline
roller:
https://www.lowes.com/pd/Saint-Gobai...g-Tool/3094501

.... which I have around here somewhere, but I don't use on patches.
Instead, I use two wooden dowels, about 3/4" = 19mm diameter. One is
held horizontally in the bench vise and forms the work surface for the
careful cleaning, scrubbing, cement application etc. Once the patch is
applied I "stitch" it by using two hands to roll the other dowel
perpendicular to the first, much like a baker's rolling pin. This
applies lots of pressure.

I agree with #1 = cleanliness. I've never done mistake #2, wet cement.
But for me, tip #3 is taking my time and being careful to get it exactly
right.

One of my first tours ended with a badly patched tube that leaked slowly
and couldn't be improved. The rest of the day was spent pumping it up,
riding a couple miles, and repeating, all the way home.

That burned in my brain to first, change to a spare tube; next, patch
the original at home, carefully, in comfort.


--
- Frank Krygowski

On Thu, 30 Apr 2020 20:11:58 -0400, Frank Krygowski
wrote:

On 4/30/2020 4:35 PM, AMuzi wrote:
On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse than other
rubber patching products.

That said, some old guys in the motorcycle/auto tire business would do
that- scuff, blow clean with compressed air and then wet the area
liberally with rubber cement. After a couple of minutes' wait, he would
draw a blade across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface. Slap patch on
and press well with a patch stitcher[1] and you're golden.

When I was young, patching tubes was all day every day (labor was cheap,
tubes were expensive) and we used the Tech brand patching system.* Scrub
area clean with Tech Buffer (mostly trichlorethylene) on a clean cloth
which removes a striking amount of black scum.* Then just wet an area
slightly larger than the patch- not drippy or gloppy, just enough to wet
the area. It will look dry in well under a minute.* Press down patch and
stitch it home. I had a failure or two in a year doing a couple dozen a
day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get the area clean
and you're well on your way to a successful patch.
#2 by frequency is slapping a patch over wet cement. That makes the
patch deform with wrinkles, which leak. Customers bring those in (I
bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg

The patch stitcher looks remarkably similar to a window screen spline
roller:
https://www.lowes.com/pd/Saint-Gobai...g-Tool/3094501

... which I have around here somewhere, but I don't use on patches.
Instead, I use two wooden dowels, about 3/4" = 19mm diameter. One is
held horizontally in the bench vise and forms the work surface for the
careful cleaning, scrubbing, cement application etc. Once the patch is
applied I "stitch" it by using two hands to roll the other dowel
perpendicular to the first, much like a baker's rolling pin. This
applies lots of pressure.

I agree with #1 = cleanliness. I've never done mistake #2, wet cement.
But for me, tip #3 is taking my time and being careful to get it exactly
right.

One of my first tours ended with a badly patched tube that leaked slowly
and couldn't be improved. The rest of the day was spent pumping it up,
riding a couple miles, and repeating, all the way home.

That burned in my brain to first, change to a spare tube; next, patch
the original at home, carefully, in comfort.

:-) Anyone that rode in the days of tubular tires would be
accustomed to the change it here and fix it at home routine :-)
--
cheers,

John B.

On 4/30/2020 10:02 PM, John B. wrote:
On Thu, 30 Apr 2020 20:11:58 -0400, Frank Krygowski
wrote:

On 4/30/2020 4:35 PM, AMuzi wrote:
On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse than other
rubber patching products.

That said, some old guys in the motorcycle/auto tire business would do
that- scuff, blow clean with compressed air and then wet the area
liberally with rubber cement. After a couple of minutes' wait, he would
draw a blade across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface. Slap patch on
and press well with a patch stitcher[1] and you're golden.

When I was young, patching tubes was all day every day (labor was cheap,
tubes were expensive) and we used the Tech brand patching system. Scrub
area clean with Tech Buffer (mostly trichlorethylene) on a clean cloth
which removes a striking amount of black scum. Then just wet an area
slightly larger than the patch- not drippy or gloppy, just enough to wet
the area. It will look dry in well under a minute. Press down patch and
stitch it home. I had a failure or two in a year doing a couple dozen a
day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get the area clean
and you're well on your way to a successful patch.
#2 by frequency is slapping a patch over wet cement. That makes the
patch deform with wrinkles, which leak. Customers bring those in (I
bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg

The patch stitcher looks remarkably similar to a window screen spline
roller:
https://www.lowes.com/pd/Saint-Gobai...g-Tool/3094501

... which I have around here somewhere, but I don't use on patches.
Instead, I use two wooden dowels, about 3/4" = 19mm diameter. One is
held horizontally in the bench vise and forms the work surface for the
careful cleaning, scrubbing, cement application etc. Once the patch is
applied I "stitch" it by using two hands to roll the other dowel
perpendicular to the first, much like a baker's rolling pin. This
applies lots of pressure.

I agree with #1 = cleanliness. I've never done mistake #2, wet cement.
But for me, tip #3 is taking my time and being careful to get it exactly
right.

One of my first tours ended with a badly patched tube that leaked slowly
and couldn't be improved. The rest of the day was spent pumping it up,
riding a couple miles, and repeating, all the way home.

That burned in my brain to first, change to a spare tube; next, patch
the original at home, carefully, in comfort.

:-) Anyone that rode in the days of tubular tires would be
accustomed to the change it here and fix it at home routine :-)
--
cheers,

John B.


Yes, seems like so long ago. 20 March, 2020 was my most recent.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Thu, 30 Apr 2020 22:26:40 -0500, AMuzi wrote:

On 4/30/2020 10:02 PM, John B. wrote:
On Thu, 30 Apr 2020 20:11:58 -0400, Frank Krygowski
wrote:

On 4/30/2020 4:35 PM, AMuzi wrote:
On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse than other
rubber patching products.

That said, some old guys in the motorcycle/auto tire business would do
that- scuff, blow clean with compressed air and then wet the area
liberally with rubber cement. After a couple of minutes' wait, he would
draw a blade across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface. Slap patch on
and press well with a patch stitcher[1] and you're golden.

When I was young, patching tubes was all day every day (labor was cheap,
tubes were expensive) and we used the Tech brand patching system. Scrub
area clean with Tech Buffer (mostly trichlorethylene) on a clean cloth
which removes a striking amount of black scum. Then just wet an area
slightly larger than the patch- not drippy or gloppy, just enough to wet
the area. It will look dry in well under a minute. Press down patch and
stitch it home. I had a failure or two in a year doing a couple dozen a
day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get the area clean
and you're well on your way to a successful patch.
#2 by frequency is slapping a patch over wet cement. That makes the
patch deform with wrinkles, which leak. Customers bring those in (I
bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg

The patch stitcher looks remarkably similar to a window screen spline
roller:
https://www.lowes.com/pd/Saint-Gobai...g-Tool/3094501

... which I have around here somewhere, but I don't use on patches.
Instead, I use two wooden dowels, about 3/4" = 19mm diameter. One is
held horizontally in the bench vise and forms the work surface for the
careful cleaning, scrubbing, cement application etc. Once the patch is
applied I "stitch" it by using two hands to roll the other dowel
perpendicular to the first, much like a baker's rolling pin. This
applies lots of pressure.

I agree with #1 = cleanliness. I've never done mistake #2, wet cement.
But for me, tip #3 is taking my time and being careful to get it exactly
right.

One of my first tours ended with a badly patched tube that leaked slowly
and couldn't be improved. The rest of the day was spent pumping it up,
riding a couple miles, and repeating, all the way home.

That burned in my brain to first, change to a spare tube; next, patch
the original at home, carefully, in comfort.

:-) Anyone that rode in the days of tubular tires would be
accustomed to the change it here and fix it at home routine :-)
--
cheers,

John B.


Yes, seems like so long ago. 20 March, 2020 was my most recent.

I came across a set of tubular wheels at a swap meet a while back and
thought about converting (regressing?). And than I remembered those
evenings sewing up tires with dental floss ( I seem to remember was
recommended ) and decided that just maybe I could get along with
conventional tires and tubes a bit longer :-)

The wife is the seamstress in the family but somehow I never could
interest her is sewing tires :-)
--
cheers,

John B.

On 5/1/2020 12:07 AM, John B. wrote:
On Thu, 30 Apr 2020 22:26:40 -0500, AMuzi wrote:

On 4/30/2020 10:02 PM, John B. wrote:
On Thu, 30 Apr 2020 20:11:58 -0400, Frank Krygowski
wrote:

On 4/30/2020 4:35 PM, AMuzi wrote:
On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse than other
rubber patching products.

That said, some old guys in the motorcycle/auto tire business would do
that- scuff, blow clean with compressed air and then wet the area
liberally with rubber cement. After a couple of minutes' wait, he would
draw a blade across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface. Slap patch on
and press well with a patch stitcher[1] and you're golden.

When I was young, patching tubes was all day every day (labor was cheap,
tubes were expensive) and we used the Tech brand patching system. Scrub
area clean with Tech Buffer (mostly trichlorethylene) on a clean cloth
which removes a striking amount of black scum. Then just wet an area
slightly larger than the patch- not drippy or gloppy, just enough to wet
the area. It will look dry in well under a minute. Press down patch and
stitch it home. I had a failure or two in a year doing a couple dozen a
day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get the area clean
and you're well on your way to a successful patch.
#2 by frequency is slapping a patch over wet cement. That makes the
patch deform with wrinkles, which leak. Customers bring those in (I
bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg

The patch stitcher looks remarkably similar to a window screen spline
roller:
https://www.lowes.com/pd/Saint-Gobai...g-Tool/3094501

... which I have around here somewhere, but I don't use on patches.
Instead, I use two wooden dowels, about 3/4" = 19mm diameter. One is
held horizontally in the bench vise and forms the work surface for the
careful cleaning, scrubbing, cement application etc. Once the patch is
applied I "stitch" it by using two hands to roll the other dowel
perpendicular to the first, much like a baker's rolling pin. This
applies lots of pressure.

I agree with #1 = cleanliness. I've never done mistake #2, wet cement.
But for me, tip #3 is taking my time and being careful to get it exactly
right.

One of my first tours ended with a badly patched tube that leaked slowly
and couldn't be improved. The rest of the day was spent pumping it up,
riding a couple miles, and repeating, all the way home.

That burned in my brain to first, change to a spare tube; next, patch
the original at home, carefully, in comfort.

:-) Anyone that rode in the days of tubular tires would be
accustomed to the change it here and fix it at home routine :-)
--
cheers,

John B.


Yes, seems like so long ago. 20 March, 2020 was my most recent.

I came across a set of tubular wheels at a swap meet a while back and
thought about converting (regressing?). And than I remembered those
evenings sewing up tires with dental floss ( I seem to remember was
recommended ) and decided that just maybe I could get along with
conventional tires and tubes a bit longer :-)

The wife is the seamstress in the family but somehow I never could
interest her is sewing tires :-)
--
cheers,

John B.


When a cheap tubular was $5 and a silk racing tubular was
$12, my $1.20 per hour wage led me to patch and sew
everything and anything, even other riders' castoff tires.

Today a good tubular is under $20 and I just toss out 3 or 4
a year. Hell, a set of Michelin Pro with Michelin tubes and
a rim liners is $200. I leave the arithmetic to the reader.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Fri, 01 May 2020 08:52:28 -0500, AMuzi wrote:

On 5/1/2020 12:07 AM, John B. wrote:
On Thu, 30 Apr 2020 22:26:40 -0500, AMuzi wrote:

On 4/30/2020 10:02 PM, John B. wrote:
On Thu, 30 Apr 2020 20:11:58 -0400, Frank Krygowski
wrote:

On 4/30/2020 4:35 PM, AMuzi wrote:
On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse than other
rubber patching products.

That said, some old guys in the motorcycle/auto tire business would do
that- scuff, blow clean with compressed air and then wet the area
liberally with rubber cement. After a couple of minutes' wait, he would
draw a blade across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface. Slap patch on
and press well with a patch stitcher[1] and you're golden.

When I was young, patching tubes was all day every day (labor was cheap,
tubes were expensive) and we used the Tech brand patching system. Scrub
area clean with Tech Buffer (mostly trichlorethylene) on a clean cloth
which removes a striking amount of black scum. Then just wet an area
slightly larger than the patch- not drippy or gloppy, just enough to wet
the area. It will look dry in well under a minute. Press down patch and
stitch it home. I had a failure or two in a year doing a couple dozen a
day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get the area clean
and you're well on your way to a successful patch.
#2 by frequency is slapping a patch over wet cement. That makes the
patch deform with wrinkles, which leak. Customers bring those in (I
bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg

The patch stitcher looks remarkably similar to a window screen spline
roller:
https://www.lowes.com/pd/Saint-Gobai...g-Tool/3094501

... which I have around here somewhere, but I don't use on patches.
Instead, I use two wooden dowels, about 3/4" = 19mm diameter. One is
held horizontally in the bench vise and forms the work surface for the
careful cleaning, scrubbing, cement application etc. Once the patch is
applied I "stitch" it by using two hands to roll the other dowel
perpendicular to the first, much like a baker's rolling pin. This
applies lots of pressure.

I agree with #1 = cleanliness. I've never done mistake #2, wet cement.
But for me, tip #3 is taking my time and being careful to get it exactly
right.

One of my first tours ended with a badly patched tube that leaked slowly
and couldn't be improved. The rest of the day was spent pumping it up,
riding a couple miles, and repeating, all the way home.

That burned in my brain to first, change to a spare tube; next, patch
the original at home, carefully, in comfort.

:-) Anyone that rode in the days of tubular tires would be
accustomed to the change it here and fix it at home routine :-)
--
cheers,

John B.


Yes, seems like so long ago. 20 March, 2020 was my most recent.

I came across a set of tubular wheels at a swap meet a while back and
thought about converting (regressing?). And than I remembered those
evenings sewing up tires with dental floss ( I seem to remember was
recommended ) and decided that just maybe I could get along with
conventional tires and tubes a bit longer :-)

The wife is the seamstress in the family but somehow I never could
interest her is sewing tires :-)
--
cheers,

John B.


When a cheap tubular was $5 and a silk racing tubular was
$12, my $1.20 per hour wage led me to patch and sew
everything and anything, even other riders' castoff tires.

Today a good tubular is under $20 and I just toss out 3 or 4
a year. Hell, a set of Michelin Pro with Michelin tubes and
a rim liners is $200. I leave the arithmetic to the reader.

Ah Ha! You left out your per hour wage :-)
--
cheers,

John B.

On Thursday, April 30, 2020 at 1:35:30 PM UTC-7, AMuzi wrote:
On 4/30/2020 3:07 PM, Joerg wrote:
Got a tear in a thick tube, possibly a production defect.
Upon hints from this NG I bought Slime Rubber Cement a
couple years ago:

https://shop.slime.com/products/rubb...nt=47493356552


The instructions say:


PROPER USE:
• Buff area around puncture lightly, removing loose
particles and making sure
entire area within 1/2" of puncture has roughened appearance.
• Brush on a moderate amount of rubber cement onto roughened
surface and
spread evenly. Work into material and scrape off excess.
• Remove backing from patch without touching exposed surface.
• Apply repair material directly over puncture and press
firmly, especially
around the edges.


No mention of the usual "Let dry for 5min". Do I have to put
the patch into the wet rubber cement?

What does "work into material" and "scrape off excess" mean?

Main reason I ask is that a similar repair attempted with
letting it dry first resulted in the patch literally falling
off. So it does not seem to be the same stuff that's in the
little patch kit tubes.


I don't know if their product is different, better, worse
than other rubber patching products.

That said, some old guys in the motorcycle/auto tire
business would do that- scuff, blow clean with compressed
air and then wet the area liberally with rubber cement.
After a couple of minutes' wait, he would draw a blade
across the surface, removing a thick black smear of
cement/crud and leaving a prepped, clean, tacky surface.
Slap patch on and press well with a patch stitcher[1] and
you're golden.

When I was young, patching tubes was all day every day
(labor was cheap, tubes were expensive) and we used the Tech
brand patching system. Scrub area clean with Tech Buffer
(mostly trichlorethylene) on a clean cloth which removes a
striking amount of black scum. Then just wet an area
slightly larger than the patch- not drippy or gloppy, just
enough to wet the area. It will look dry in well under a
minute. Press down patch and stitch it home. I had a
failure or two in a year doing a couple dozen a day every day.

Your directions seem to be a mix of both methods.

IME #1 cause of patch failure is lack of cleanliness. Get
the area clean and you're well on your way to a successful
patch.
#2 by frequency is slapping a patch over wet cement. That
makes the patch deform with wrinkles, which leak. Customers
bring those in (I bought this patch kit- it's no good) still.

[1] looks much like a pizza cutter but with a blunt 5mm wide
outer rim:
https://www.picclickimg.com/d/l400/p...Dia-Roller.jpg

#3 reason for patch failu using an actual pizza cutter for stitching.

Some brands of tube have a really persistent mold release or other surface treatment that makes it really hard to get good adhesion with normal prep with sand paper. I don't typically use solvent, but I might on a couple of odd ball tubes I own.

-- Jay Beattie.