Clamptite makes a neat tool for forming wire ties. It's function is described on their website... http://www.clamptitetools.com/ [Be sure to watch the videos describing its use.] I had an application for such a tool but I really didn't want to lay out the $70 for what seems to me to be a pretty simple thing. So, muttering to myself "this is why I have a machine shop", I made my own... The body is half-inch 12L14, the screw is 1/4-28 and the pins are 3/32" roll pins. The tip has a shallow 1/16" wide slot milled into it to anchor the wire when making double wraps... Shown in the first picture is one of my uses for it - securing silicone aquarium air tubing to brass fittings with a double wrap of soft iron florist wire. If I were to use heavier wire such as safety wire, I would probably make a larger version of the tool but, for now, this one does what I need.