tube patch 'blows a bubble' then pops

[Larry English]

several times, i have had a tube patch 'blow a bubble' at the edge of the patch, then the
bubble pops.

it;s almost like an orange bubble gum bubble.

the patch had been on there for weeks, it wasn;t fresh.

what causes this?

can you patch over a patch?

this is even worse - the corner of a patch, which of course is even more likely to leak.

?, wle.

 

[Ken]

[email protected] (larry english) wrote in news:abbf1007.0308130750.38efd665 @posting.google.com:
> several times, i have had a tube patch 'blow a bubble' at the edge of the patch, then the
> bubble pops.

Sounds like the patch wasn't bonded properly the first time. Use the sandpaper in the patch kit to
carefully clean the entire patch area. If you're using a glue-on type patch, make sure you use
enough glue to cover the entire patch area (and a little more).

 

[Arthur Shapiro]

In article <[email protected]>, [email protected] (larry english) wrote:
>several times, i have had a tube patch 'blow a bubble' at the edge of the patch, then the
>bubble pops.
>
Is it perhaps possible that you got a "snake bite" puncture (two parallel small slits due to
"bottoming out" on a hard bump) and only noticed one of 'em? The patch might coincientally barely
cover the second hole, and be likely to fail over time.

If not, the first suggestion is right on. The reason most people can't get patches to hold is that
they don't sand enough. I use a sanding drum in a Dremel tool, which requires a little bit of
practice to avoid destroying the tube. It has been claimed in this group that any sort of
hydrocarbon solvent that removes the glossy sheen from the tube will be sufficient, but that
approach won't remove the ridges and other embossed patterns in the tube that always seem to be in
the area of the puncture.

A properly applied Rema patch will not fail.

Art

 

[Mikeyankee]

Something isn't sticking right...

If it's a glued patch sand the tube, apply "glue" (actually vulcanizing fluid) and LET IT DRY, then
put the patch on and hold it in place with firm pressure for a few seconds.

Sanding is important when using quickie pre-glued patches, too.

Mike Yankee

(Address is munged to thwart spammers. To reply, delete everything after "com".)

 

[Werehatrack]

On 13 Aug 2003 08:50:07 -0700, [email protected] (larry english) may have said:

>several times, i have had a tube patch 'blow a bubble' at the edge of the patch, then the
>bubble pops.
>
>it;s almost like an orange bubble gum bubble.
>
>the patch had been on there for weeks, it wasn;t fresh.
>
>what causes this?

This used to happen to me years ago whenever I got in too much of a hurry fixing a puncture that was
adjacent to a molding ridge in the tube's surface. If the area around the hole wasn't completely
flat, the patch had to be clamped under a fair amount of pressure while the glue bonded..and then it
eventually failed anyway. I learned to make use of the sandpaper to remove that ridge before
applying the glue. I also learned that a diamond-grit coarse nail file can come in handy at such
times; it stays sharp a lot longer than sandpaper. Modern tubes don't seem to be as heavily
afflicted with the surface features that I used to see, so the need for buffing is less than it was
back then...but not entirely absent.

>can you patch over a patch?

I wouldn't recommend it, for a variety of reasons, not all of which apply at the same time.

>this is even worse - the corner of a patch, which of course is even more likely to leak.

I have seen little or no difference in the results obtained with round vs square patches, and can't
recall that corners of square patches were prone to any more problems than anywhere else. I'd say
that location has more to do with the likelihood of a patch failing than anything else. My
experience has been that the number one least successful patch locale is adjacent to the stem; if I
get a leak there, I trash the tube and throw a new one in.

--
My email address is antispammed; pull WEEDS if replying via e-mail. Yes, I have a killfile. If I
don't respond to something, it's also possible that I'm busy.

 

[Jobst Brandt]

Arthur Shapiro writes:

>> several times, i have had a tube patch 'blow a bubble' at the edge of the patch, then the
>> bubble pops.

> Is it perhaps possible that you got a "snake bite" puncture (two parallel small slits due to
> "bottoming out" on a hard bump) and only noticed one of 'em? The patch might coincidentally barely
> cover the second hole, and be likely to fail over time.

I'm with you on that. The symptom points directly at that. However, it might be worthwhile to review
the FAQ patching item.

http://draco.acs.uci.edu/rbfaq/FAQ/8b.1.html

Jobst Brandt [email protected] Palo Alto CA

 

[Tbgibb]

In article <[email protected]>, [email protected] (larry
english) writes:

>several times, i have had a tube patch 'blow a bubble' at the edge of the patch, then the
>bubble pops.
>
>it;s almost like an orange bubble gum bubble.
>
>the patch had been on there for weeks, it wasn;t fresh.
>
>what causes this?

Inadequate prep with the sand paper or not allowing the glue to dry before putting the patch on
comes to mind (from my own mistakes).

>can you patch over a patch?

I do regularly.

Tom Gibb <[email protected]

 

[David Kunz]

Werehatrack wrote:

> On 13 Aug 2003 08:50:07 -0700, [email protected] (larry english) may have said:
>
>
>>several times, i have had a tube patch 'blow a bubble' at the edge of the patch, then the
>>bubble pops.
>>
>>it;s almost like an orange bubble gum bubble.
>>
>>the patch had been on there for weeks, it wasn;t fresh.
>>
>>what causes this?
>
>
> This used to happen to me years ago whenever I got in too much of a hurry fixing a puncture that
> was adjacent to a molding ridge in the tube's surface. If the area around the hole wasn't
> completely flat, the patch had to be clamped under a fair amount of pressure while the glue
> bonded..and then it eventually failed anyway. I learned to make use of the sandpaper to remove
> that ridge before applying the glue. I also learned that a diamond-grit coarse nail file can come
> in handy at such times; it stays sharp a lot longer than sandpaper. Modern tubes don't seem to be
> as heavily afflicted with the surface features that I used to see, so the need for buffing is less
> than it was back then...but not entirely absent.

Not sure that I'd agree with this. I've had no problems at all with ridges or texture as long as I
carefully sand all of the mould release off of the tube (no shiny or non-jet black places where the
patch goes), get glue everywhere and let it dry well (very important), and press the patch firmly
all over -- repeatedly to make sure that I didn't miss any places.

David

 

[Larry English]

[email protected] (Arthur Shapiro) wrote in message news:<[email protected]>...
> In article <[email protected]>, [email protected] (larry
> english) wrote:
> >several times, i have had a tube patch 'blow a bubble' at the edge of the patch, then the
> >bubble pops.
> >
> Is it perhaps possible that you got a "snake bite" puncture (two parallel small slits due to
> "bottoming out" on a hard bump) and only noticed one of 'em?

possibly.

> The patch might coincientally barely cover the second hole, and be likely to fail over time.
>
> If not, the first suggestion is right on. The reason most people can't get patches to hold is that
> they don't sand enough.

i thought i read somewhere that the point was just to rough it up a little.

i didn;t think you had to grind it flat.

though it makes sense that ridges are going to cause a problem.

this one wasn;t near a ridge though.

wle.