ground and polished square bar

[darryl]

A recent post had me suggesting such a thing, not knowing if it was available. It's been in my mind, so I tried to find something like this. The closest I came up with is 4140HT square bar. I couldn't find relevant specs, like you can for TGP. In particular I was looking for dimensional tolerances, and also squareness and straightness- all factors to consider if you were going to use it for ways. As an alternative to round ways, it would have its advantages.

The 4140HT was priced at about $10 per foot for 1 inch square, which isn't bad if the qualities would suffice. Has anybody gone down this road?

[Peter S]

For short lengths (300mm), key steel is ground (not hardened or polished), available in a large range of sizes, rectangular and square. Not sure what the usual material is, probably mild steel. Also available in stainless.

Good for special parallels in the milling vice, if nothing else.

[Toolguy]

Look at precision flat ground in McMaster-Carr or MSC. They have many square and rectangle sizes in Low Carbon and Tool Steel, 18" or 36" lengths. Key stock is usually way soft. I would not use it for slideways.