Thread: What happened to vulcanising patches?

Probably the same thing that happenned to records and carbies. Things progress and sometimes improve leaving old technology behind

Glad to see that I'm not the only one who has come across this.

I went through exactly the same a while back when helping my daughter fix a punctured tube on her bike. And - I was actually told at the time by the owner of the local bike shop (his younger employees didn't even know what we were talking about) that vulcanising kits had long since been removed from the market due to the dangers they posed to people being burnt.

I hope these idiots never realize that some of us still use hot water to soften the ends of a garden hose before inserting brass hose fittings - next they'll be banning the kettle.

Originally Posted by BMKal

.... Glad to see that I'm not the only one who has come across this. ....

^ x2 ^

I eventually found some and last time I looked, the Auto Spares Galore in Ferntree Gully (Vic) had some for about $5.00 ea ... from NZ I think they were.

(I heard something about the smoke from burning the pad being carcinogenic????)

Stevo

Just rang them ... In stock ... I'd better get some more.

i have to repair 30 fire hoses on Monday

and all are vulcanized patches
its the only form of patch strong enough

I don't think I've ever used a vulcanised patch on a bike tube, even when I was a kid we used to use glue patches.

Hose patching is now a mix of vulcanised and glued patches, depending on the hose. How long since any one took a tyre to be repaired (those still running tubes) and they applied a vulcanising patch - certainly not me in the last 20 years.

However I would suspect breathing the fumes from some of the glues would be more harmful than a small contact burn - just not immediate

I do however still, have some of the small clamp on vulcanising patches.


Martyn

You must only be a young fella then Bushie.

When I was riding bikes as a kid, the ONLY way we had of mending punctures was with vulcanised patches. I had never even seen a glued patch until much later on. I remember having a small leather pouch hanging from the back of my bycicle seat which had the basic tools, wheel spanner, tyre levers, vulcanising clamp and a shiny almost oval shaped tin, the bottom of which was a bit like a cheese grater to "rough up" the area of the tube to be patched, and containing a number of vulcanising patches inside.

Of course, none of the above was of much use to you if you didnt have a bicycle pump and a box of matches with you.

There is a good discussion on the merits (or lack thereof) of the old style patches here. http://www.bikeforums.net/archive/in.../t-446003.html

Note some of the new style patch kits advertise themselves as "vulcanising patches" Park Tool Website

Also from wikipedia...

Room Temperature Vulcanization

Room temperature vulcanizing (RTV) silicone is constructed of reactive oil base polymers combined with strengthening mineral fillers. There are two types of Room temperature vulcanizing silicone:

RTV-1 (One-component systems)

RTV-1 hardens directly under the action of atmospheric humidity. The curing process begins on the outer surface and progresses through to its core. The product is packed in airtight cartridges and is either in a fluid or paste form. RTV-1 silicone has good adhesion, elasticity and durability characteristics. The Shore A hardness can be varied between 18 and 60. Elongation at break can range from 150% up to 700%. They have excellent ageing resistance due to superior resistance to UV radiation and weathering. Industrial RTV-1 products are referred to as CAFs.

RTV-2 (Two-component systems)

RTV-2 elastomer are two-component products that, when mixed, cure at room temperature to a solid elastomer, a gel, or a flexible foam. RTV-2 remains flexible from -80°C to +250°C. Break down occurs at temperatures above 350°C leaving an inert silica deposit that is non-flammable and non-combustible. They can be used for electrical insulation due to their dielectric properties. Mechanical properties are satisfactory. RTV-2 is used to make flexible moulds, as well as many technical parts for industry and paramedical applications.

The bottom line is that the world has moved on. I am (just) old enough to remember the old-style patches, and they were a PITA.

I have done literally hundreds of bike tube repairs using the glue-on patches, and NEVER had a patch fail. And this is on DH bikes where the tubes have to cope with hard hits and being run at low pressure (much like a 4x4 tyre).

still available if you know where to look. no longer really cost effective.


I use them to patch the inside of agricultural tubeless tyres