Greetings,
I'm looking at making my own plane blades (and other tools, too). I
found OnlineMetals.com has O-1 in the appropriate sizes. I've got some
chip-carving blades (nee hacksaw) tempering in the oven right now.

It occurred to me as I removed oxidation from the blades after
hardening that for a 2" by, say, 3/16" blade, I should really be
ordering 2.5" x 1/4" (or 7/32") stock. True?

Thanks for your advice
--
"Keep your ass behind you."


Why would you want to do that?

Two main reasons for starting with oversize stock.

To allow grinding to final size after hardening, to take care of any warping
from the hardening process. In your case, the final size is not critical, and
a slightly warped blade will be flattened out when it is clamped down.

To get past any scale or surface decarburization. If you have a heat treating
oven, you probably already know about the use of stainless foil or anti-scale
coatings.

Do you have a surface grinder? If you do, go ahead with the oversize stock.

John Martin