What size steel for a bread knife?

A bread knife is long and thin rather than tall. The preset is a 9 in blade, 1 1/4 in tall at the heel, with a 5/64 in spine (0.078 in, about 2 mm) and a 5 in full tang. The heel sets the width: 1 1/4 in plus 1/8 in of clean-up is 1 3/8 in, so the bar is 1 1/2 in wide, and the 5/64 in spine rounds up to 3/32 in stock. It is a stock removal job. The calculator starts on 1084 and warns that a 0.078 in spine is under the 0.090 in it treats as practical for 1084, which can warp in the quench. A fine-grained stainless suits this knife better. AEB-L was developed in the 1960s as a stainless razor-blade steel. Its carbides are a micron or less, and Larrin Thomas lists it for kitchen knives; the calculator's practical floor for it is 0.060 in. Alleima markets 14C28N for knives that need a very sharp edge, chef's knives among them. Switch the calculator to either one and it reworks the bar and weights for that steel's stock sizes.

The serrations are cut after the profile, so the bar is sized for a plain blank: 14 1/4 in of 1 1/2 × 3/32 in bar per blade with clean-up, three to a 48 in bar. Grinding the teeth only takes steel away. Some makers on BladeForums cut them with a round chainsaw file (3/8 in is one suggested size), seating a rod of the same diameter in the last gullet to space the next one. Others use a 1 in or 3/4 in grinder wheel, holding the blade at about 15 to 20 degrees so each scallop gets its own bevel, or cut them after hardening on a small 1/4 to 3/8 in wheel with fresh belts and frequent cooling. A rotary tool with a chainsaw-sharpening stone also works if you go slowly and keep the steel cool. If you file them, do it before heat treat, because ordinary files won't cut hardened steel. One maker leaves them a little undersize and finishes them after hardening with a round diamond file or sandpaper wrapped on a rod.

What a bread knife is for

A bread knife has to get through a hard crust without crushing the soft crumb under it. With a thick, crunchy crust, any downward pressure squashes the crumb, as one BladeForums poster points out, so a serrated edge lets you saw through instead of pushing down. Serrations are not the only answer, though. Several makers in the same discussions say a thin, sharp plain edge cuts fresh bread fine, and one advises talking the customer out of serrations altogether. Ask before you start grinding teeth.

The loaf sets the length. America's Test Kitchen wanted at least 8 1/2 in of usable serrated edge, enough to get across a big sourdough loaf, and bread knives generally run from about 6 to 14 in. Height matters too: in the same testing, blades averaging under 1 in tall were too flexible, and testers preferred an average over 1.3 in for control, so the 1 1/4 in heel here is on the modest side and the long variant goes to 1 1/2 in. ATK also found that tall, pointed serrations grip food better than short or scalloped (rounded) ones, which sometimes skid over the surface. Its best-rated knives had 29 to 34 serrations, and blades with more than four per inch gripped less well. Scallops still have their uses in the shop: one maker suggests sizing them to the rod or slip you will sharpen with, and wide ones are easier to touch up than narrow ones. Offset bread knives drop the blade below the handle so your knuckles clear the board as you cut through. ATK liked that clearance but marked the offset knives down for their short blades. An offset blank is taller than this one, so put its full height into the calculator.

None of this is settled, so treat it as a story rather than history. Who invented the serrated bread knife is told several ways, and the accounts conflict. Syracuse histories credit Joseph E. Burns with inventing it in 1919, and a New York pocketknife history database adds that the idea came to him while using a scallop-edged glass-cutting tool. His patent is on record: US 1,388,547, "Cutting Tool", filed in September 1919 and issued in August 1921, for a bread knife with groups of grooves angled in opposite directions and separated by plain sections, so it cuts when drawn either way. Whether it was the first is another matter. Wikipedia, citing the company, says the German maker Friedr. Dick showed a bread knife at the 1893 World's Columbian Exposition in Chicago and has made serrated knives since 1889. It also cites a 2010 article in the Early American Industries Association's Chronicle on American serrated and saw-cut knives going back to 1838. Bernal Cutlery puts today's familiar serrated shape later still, in the mid-20th century, as a slimmed-down version of the plain-edged German Hamburg bread knife.

Stock for a bread knife

One maker on BladeForums grinds his W2 bread knife to 0.079 in at the spine where it meets the handle, takes the bevels to zero and then puts on an edge of 12 or 13 degrees per side. That matches the preset's 5/64 in spine and leaves a little of the 3/32 in bar for flattening and clean-up.

Widths assume blade height + 1/8 in rounded up to stock; thickness is the finished spine rounded up. Change the inputs above for your own pattern.

Steels that suit it

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