Re: make - forge? - wedge for feathers-and-wedge rock-split

On 28/03/2024 17:53, Richard Smith wrote:

Making them anew with something like forging could be a good project.
If so what steel would you use?  AISI1075? (C-Mn; 0.75%C).  If so -
"spring-temper"?

I'd probably use O1 ground flat stock, but only because it is readily available. Can be cut on a bandsaw in as-it-arrives condition. Not cheap, but you can sometimes find a deal.
Slowly heat to red-orange, soak for 15 minutes. Quench in hot oil, then immediately temper well, don't let it cool from hot oil temperature: you don't want it too hard - maybe an hour or two at 250 C. You'll still be around 60 Rockwell C.
Not sure if you can spring temper O1. I wouldn't try it here.
That old favourite EN24T might work too, but it is hard to find except in round bar.

We have something called "silver steel" which is "(centreless-?) ground
0.8%C steel" (ie. right on the eutectoid).

It's great for hard stuff like knives or screwdrivers: but if you need impact resistance you have to temper it so much it gets soft; or at least that's my limited experience, ymmv. I know some people have used it for punches.
Another problem is, again, it's only really available in round bar.
Peter Fairbrother