Hi Shoestring.

Favourite trick for a single pinhole in a tube, if you can get at it, is fill the hole with something like petrol tank repair putty --- obviously we're only talking about a crumb of the stuff -- and simply crimp the tube together above and below the hole, as a belt and braces job. (I'm guessing we're looking at an ally rad ?.

Mike.

Hi on the cut,
I'll scrape some paint off the old rad and get back to you on that.
shoestring