wrote:
On Saturday, August 11, 2018 at 1:18:40 PM UTC+2, John B. Slocomb wrote:
On Fri, 10 Aug 2018 22:56:16 -0700 (PDT), wrote:

On Saturday, August 11, 2018 at 1:07:58 AM UTC+2, John B. Slocomb wrote:
On Fri, 10 Aug 2018 15:36:07 -0700 (PDT), jbeattie
wrote:

On Friday, August 10, 2018 at 12:33:29 PM UTC-7, Frank Krygowski wrote:
On 8/10/2018 3:09 PM, David Scheidt wrote:
Andy wrote:

:I sanded the tube, applied the patch and clamped it in a vise for an hour.

Did you let the glue dry? the hexane (or whatever they use these
days) is just a solvent. the active part of the glue is the rubber
and vulcanizing activator. then put the
patch on, and press firm (the edge of a patch kit box works great.).
Then put the tube to use.

Here's my method:

First, I seldom patch a tube at the side of the road. Instead I just
change tubes, using the spare tube I always have with the bike. I do
check carefully by feel and visually to be sure the glass, wire or
whatever is not still sticking into the tire. Oh, and I make sure the
punctured tube is tossed sloppily into my handlebar bag so I don't
forget to deal with it at home.

At home, I inflate the tube and find the leak, making sure there isn't
more than one. I mark its position X with chalk.

I clamp a thick dowel (3/4" diameter or so) so it's protruding from my
bench vise. This is my work surface. I lay the X directly on top.

I take my sanding block (used for wood work) and sand the area to be
patched. It's way easier than fiddling with the tiny sandpaper in a
patch kit, and the dowel work surface makes it easy to sand well.

I apply the patch glue, spreading it thin, then wait maybe five minutes
for it to dry.

I peel the backing foil off the patch and carefully stick it in place.

Then I take another dowel, hold it right angles to the one in the vise,
and roll it over the patch to apply pressure, starting in the patch's
center and working toward the outside. It's like rolling cookie dough -
although I've never rolled cookie dough. This makes it easy to apply
quite a bit of force on a small area (the contact point between two
perpendicular cylinders) and I think helps make the bond very strong.

Then I make sure all the air is out of the tube so it's completely flat.
I fold it up, put a rubber band around it and put it back in my bike bag.

For me, the main thing is it's a lot easier to do this in my basement
where I have all the tools immediately ready. And the dowel in the vise
really is a much easier work surface than a flat surface.

Here's my technique -- carry a couple of spares and have boat loads
of patched and new tubes at home. Get numerous flats and accumulate
a pile of un-repaired tubes. Then, (1) select proper beer; go to
man cave and (2) select proper DVD and or BluRay movie, (3) start
patching. I use a Sharpie to mark, and I just lay the tube flat and
sand. You can apply glue to two or three at a time, depending on
chair-back hanging space. Number one dries as you're spreading glue
on three, etc. Apply patches like you say, but I just put the tube
back on flat surface (I use a plastic cutting board) and press down
with plastic tire iron. You could use your finger nail. When the
pile is done, I pump them all up and let them sit overnight. There
are always two or three that go flat because of super small holes,
and then I get out the bucket of water and do those, and then I roll
them all up like you say.

Sanding is the important part, IMO. Some tube brands have really
nasty mold release or some other finish that you have to get through for a good bond.

I have a patch limit where I just throw the tube away. Nothing set.
If I say, "man there are a lot of patches on that tube," then I just
throw it away. I've gotten my money out of it. I'll keep patching if
it has sentimental value or its some weird size that I need.

-- Jay Beattie.


A while ago I believe that we discussed patching tubes in detail. At
the time I think I remember someone writing that they simply wiped the
tube off with some chemical and slapped on the patch. No sanding.

I remember thinking that I should "get some of that stuff" but like
many plans it came a crupper and I even forgot the incident until this
thread started.

Anyone remember the details and did the scheme actually work. I hate
sanding tubes and would gladly go to some lengths to avoid it.

It was me. I never sand unless I need to patch a flat along the road
which is almost never. I use what we call in the Netherlands
'wasbenzine'. Removes the mould release nicely and you get a nice dull
black spot. It takes just seconds and I get 100% succes rate.

Lou

Thanks for that.... now to try and figure out what "wasbenzine" is :-)
Given that "benzene" means many different in different places that may
be a problem :-)

Form Wikipedia:
https://nl.wikipedia.org/wiki/Wasbenzine

In Dutch for applications (toepassingen):

Schoonmaken van binnenband (bijvoorbeeld fiets) alvorens solutie (lijm)
aan te brengen; dit werkt beter dan schuren omdat eventueel vuil wordt
opgelost en afgevoerd en niet wordt uitgesmeerd

translation; for cleaning inner tube (ie bicycle) before applying the
cement (glue); this works better than sanding because dirt is disolved
and removed instead of smeared out.

I agree with that.

Lou



From the same Wikipedia article, "met 5 tot 15 koolstofatomen volgens de
formule CnH2n+2, bijvoorbeeld C7H16". So it sounds like n-heptane would be
the English equivalent.