[email hidden] wrote in news:5fhel3pg7sgh3ktgovlv01s3at1147ssel@
4ax.com:
Quoted message said:It does seem logical that water would evaporate and escape from the
tube, just as air does, but it doesn't.
Gases like N2, O2, and CO2 are soluble in rubber, with O2 escaping
2.5~4 times as fast as N2 and CO2 escaping about 16 times as fast as
N2. It's a chemical process, not a simple matter of the rubber acting
as a physical sieve.
Water doesn't evaporate appreciably from a rubber inner tube. If
anything, the high pressure inhibits the liquid water from turning to
gas. An inner tube filled with water will be full of water next year.
A rubber lining is basically water-proof.
Stan's tire sealant is known to dry up and is explicitly stated to
require re-filling every few months. His stuff uses volatile liquids
that are soluble through rubber.
Slime doesn't seem to do that.
You can check your punctured Slime tube by grabbing the end of the
tube on the far side from the puncture and stripping it toward the
tiny hole, forcing the Slime toward the puncture. You should feel and
hear the gooshy mess moving and gurgling through the tube and see a
drop of green appear from the hole.
If it does, all is as well as it can be. The Slime is unlikely to seal
the hole in an exposed and inflated inner tube. It works (when it
does) when the pinhole in the tube is flattened against the inside of
a tire--the longer the tiny tunnel through the tube and rubber, the
more likely the Slime is to clog it.
You may be simply expecting too much from your Slime tubes. Slime
works about half the time for me on the pinpricks from goathead
thorns, enough that I find it useful. Sometimes it seals impressive
holes from things like staples, too, but usually not.
Slime certainly doesn't seal worth a damn when I'm patching the bare
tube. When I stretch the tube around the smooth round arm of a bench
vise, I have to strip the Slime away from the hole until no more green
appears and I can sandpaper the area for patching without spreading
more Slime on the rubber.
Well, perhaps Slime isn't water based. I read it is glycol based, but a
search of their website did not reveal what its constituents are. The
MSDS only said it was non-toxic. Clearly it does degrade, as Slime only
guarantees it for 2 years in a tube. The tubes that would not seal for me
were inside tires that repeatedly went flat inspite of spinning the
tires, putting the leak at the bottom, etc. I have read accounts of
others that stated it doesn't seal after so many years. If I can find the
20" tube that may still be in my garage, I'll cut it open to see if it's
dried up.
--
Larry Dickman <[email hidden]>
