Ray Iles Mortise Chisel

[William Fretwell]

Joel Moskowitz claimed in his blog that RI used D2 because Joel asked him to (about halfway down, para starting with "A few discussions"). Joel also states on the product page that he originally wanted A2 but chose D2 because it was more available in Sheffield, which is probably what you saw.

Those chisels are effectively a "bespoke product" for which Joel (TFWW) has historically been the sole distributor, so his recollection seems credible.

Found it:

"Regular modern carbon steel would be okay, but we thought that the extra toughness of A2 might be better. But in England, where these chisels are made, A2 is hard to get in the sizes we needed. So we decided on D2, a slightly more expensive, more durable, overall better tool steel."
I've not read his blog yet but did just read the slight back bevel recommendation which I had forgotten.

[Patrick Chase]

Found it:

"Regular modern carbon steel would be okay, but we thought that the extra toughness of A2 might be better. But in England, where these chisels are made, A2 is hard to get in the sizes we needed. So we decided on D2, a slightly more expensive, more durable, overall better tool steel."

Yeah, that's the bit from the product page that I was referring to. Describing D2 as "overall better" than A2 is... interesting. D2 has over twice as much Cr (12% vs 5%) and therefore much higher Chromium carbide content. Those carbides give great abrasion resistance, but when conventionally processed they result in a very coarse grain structure. As the old saw goes, D2 takes a crappy edge and holds it forever. That's perfectly fine for a mortise chisel, but I'd run screaming from D2 bench chisels or plane blades.

Powdered-metal D2-ish steels are great though. I've used two (Crucible CPM-D2 and Carpenter CTS-XHP, aka PM-V11) and they're both very nice all-round tool steels.

[Derek Cohen]

Interestingly, Patrick, I know of at least one high-end plane maker that has used D2 (as an option) in his planes for many years. That is Philip Marcou (in New Zealand). Philip is not only very knowledgeable about steel - he was also a knife maker - he has been a professional furniture maker for a few decades. Philip has said to me that it is in the heat treating. I've never pressed him on this topic, but he also speaks from a practical position.

I have a D2-bladed plane which I built. This is a single iron jack, and uses a very thick blade.



It gets very sharp, and holds it a long, long time.

Regards from Perth

Derek