patching radial tires?

Flexing of the casing.

Yes, usually.

Yes.

Probably gave you a false sense of security.

It should be obvious that a patch on the inside of a tire is likely to fail.

Just go buy a new tire if a plug doesn't work.

so not following the "stitching" procedure and possibly not letting the rubber adhesive dry

thought so. now ill have issues with 2 different patches flexing over the casing?

as long as it doesnt help the patches come off

tires are repaired all the time using patches, plugs or some combination. with proper installation, im under the impression they should become one with the tire. otherwise, why sell a product that plain doesnt work at all?

and what do the places that repair tires use?

its on order and will be here in about a week.

Yes, if they are layered over one another.

Think about the forces that work on a patch vs a plug for a minute. The plug has the greatest chance of working, but there are no guarantees.

Plugs seem to be the most frequently used in my experience.

I had my van tire repaired at a tire place once. A few months later, on the highway in the FL panhandle driving back to TX, started hearing a funny "whup whup" noise. On checking, there was a giant bubble in the tread where the fix was. Looked like air bled in between the layers of the tire.

Anyway, the tire places don't always get it right either.

I'm no expert, but have had a little experience. I used to use the sticky wick inserts a lot, and never had a failure. I liked the way they seemed to seal the inside of the puncture.

On a few occasions where the puncture was large, I would use these wicks first, then open the tire and trim off the wick and patch over it.

What I believe I have observed is that some of the internal patches seem to have a very poor adhesive and they come off no matter how clean you make the surface.

At our company garage, the head mechanic used to use a type of patch that required you to first buff the rubber with a wire wheel, then paint it with glue,and finally to ignite it with a match. After that, the patch was applied and held in place with a clamp. These seemed to hold very well.

It has been a long time since I have seen or worked with these latter patches. Maybe they dont exist anymore, and maybe they were never as good as they seemed to be.

But I believe that not all patches are created equal. Maybe someone here can give us the straight story.

Those were hot vulcanizing patches. They had a metal cup backing on them that got clamped in place with a solid fuel inside you lit on fire after the brush and glue prep. Some folks that didn't know any better used to light the glue thinking this was the same as they saw on the real ones. Kinda like if the hot patch works, lets make the glue hot. I don't believe that had much benefit.

Mike

From the tone of my post, you probably realize that I suspected as much. Still, these patches seemed to hold well. They were not dangerous as such, but if you had people pumping gasoline in the vicinity, or working with solvents, etc, then they contributed to a hazard.

I remember hot patch equipment as well. Haven't seen it in a long time.

I stand with the statement that some adhesive patches hold better than others. There is a lot of cheap crap out there. Good patches aren't free.

I don't remember using hot patches on tires themselves, only on tubes, which (to say the least) aren't widely used on passenger cars anymore.

AFAIK the hot vulcanizing patches have not been available for several decades.