As Manuel would say…'Que Mr. Fawlty..'

What did you have in mind?

Scrap bin perhaps…

As a pivot point for a lever action tailstock – it's been done before

As a total beginner I learned by painful experience to avoid practising on scrap metal. By all means have a go, but don't be surprised if it doesn't machine well.

Being a safety critical component, your track-rod will be made from a steel alloy chosen for it's strength and toughness, not because it is easy to machine. Likely it was shaped by grinding, or machining the metal in a soft state, before hardening and tempering in a furnace. Like springs, knives and old files it may be essential to heat treat it before trying to cut it. You don't know!

Other scrap can be equally nasty for other reasons – many Aluminium alloys are soft and sticky, more likely to tear than cut. Cast iron is always messy and some of it is vile to turn : beware old sash weights which are randomly good and/or bad due to impurities! Brass is usually good, unless it's phosphor Bronze…

Known alloys intended for machining are a much better bet. Mild steel is OK, and the leaded version is a joy to use. My advice is to spend some cash and learn on alloys formulated for machinability. Once you have a feel for how they behave, it's safer to try scrap. With experience of decent metal it's much easier to tell if a cutting problem is caused by the lathe, tool, or operator rather than poor choice of material.

Dave