Slow leak--arrrrrgh!

A friend of mine told me that the reason you sand the tube is to remove a
powdery chemical residue from the tube.


talc... talcum powder... baby powder. so the tube doesnt stick to itself
in storage.

Pbwalther wrote:

Why do you think your patch didn't hold?

Didn't sand a large enough area of the tube. That's easily seen.

Yes, I know. I'm an idiot.

-Luigi


A friend of mine told me that the reason you sand the tube is to remove a
powdery chemical residue from the tube. He claims that when tubes are made,
the chemical is put in the mold to allow the tubes to be removed easily. The
problem is that the glue for patches will not work on the residue. The residue
has to be removed first and that is done by sanding. I understand that you can
also remove it by using a little acetone. I have tried it and it seem to work
great. Of course, I still sand the tube just in case. Nothing like having a
backup.

your explanation works for me. I useta work in the fibreglass industry.
We would treat moulds with a very thin spray of stuff that let the
product pop away from the mould when encouraged by a shot of compressed air.
Makes sense to me. The rubber doesn't need to be roughened. It needs
to be chemically clean, so the glue can bond with the rubber with no
interference from the relaeasing compound, whatever it is.
Bernie

"Jeff Starr" wrote in message
...
I patched a tube today and in its place installed
another patched tube.

...I sand an area much larger than the
size of the patch. The same with the glue, I always cover a larger
area.

Added tip: with a pen, mark around the hole at some distance from it, like
this, where "*" is the hole:


|

- * -

|

(looks best in fixed font)

This way, after you sand and glue a generous area like Jeff suggests, you
can still get an accurate visual read on where the hole is and you can be
sure to put the middle of the patch right over the hole.

"Zoot Katz" wrote in message
...

I just tried a 75 watt light bulb. It did the job.

Zoot! Never use a 75 watt bulb where a blowtorch could do the job with more
style!
Has Fabrizio taught you nothing?

On Thu, 22 Jul 2004 14:32:12 +1000, bentbrian
wrote:
Carry a spare tube. It is cheap insurance. If you mess up patching one
you still have a spare.

Or, the much ballyhooed, and really quite good, strategy of using
the spare tube for the first flat on the road, carrying the patch
kit only for a second flat in a single ride; then, patch the tubes
in bulk.
--
Rick Onanian