On 24/04/2013 20:42, Mrcheerful wrote:

Judith wrote:

My friend has what I believe is known as an "Auto centre punch". It
doesn't require a hammer to make the punched hole.
I have a very specific requirement for punching single holes through
pieces of rubber. The diameter of the hole is not important - as
long as I can make the hole very quickly with the minimum of fuss.
Something like : apply tool to rubber item - press hard - hole made.
Does the team think that an "Auto centre punch" would do the job? Do
you think I could sharpen the point to make it more needle like - but
it still do its job. I don't want to use it just once or twice; but
need to use it on a very regular basis.
(Apologies for making the post in the cycling newsgroup - but I know
that some people here have many good ideas - much lateral thinking)

No, it would not do the job, an auto centre punch requires to be pressed
against a solid object in order to work, even if the rubber was backed by
heavy steel it is unlikely to penetrate rubber unless it was very thin. A
dart on the end of a stick would probably do what you require.

Don't tyre retailers often have a long, thin, sharp but tube-type
implement which they use to stab old tyres in order to deflate them
before removing for replacement and scrapping?

I expect it would work more easily (and with less effort) with some
sorts of tyre than it would with others.