What size steel for a puukko?

A puukko is small and narrow, so it comes out of narrow bar. The preset is a 3 3/4 in blade, 0.85 in tall at the ricasso, with a 5/32 in (about 4 mm) spine and a 4 3/4 in stick tang through a round handle with no guard. Add 1/8 in for clean-up and the height comes to 0.975 in, so 1 × 5/32 in flat bar covers it. That spine is on the heavy side for the pattern. A BladeForums poster who has handled a lot of them puts the usual puukko spine at about 1/8 in, and Finnish factory blades sold for handle-making mostly measure 0.12 to 0.13 in, though a Bushcraft UK writer notes that most modern custom Scandi knives are thicker, 4 mm and up. Drop to 1 × 1/8 in for a lighter carver. Thickness also sets how tall the Scandi bevel ends up: at about a 20° included angle, 5/32 in stock gives a bevel about 7/16 in tall, roughly half the blade, and 1/8 in stock stops nearer 3/8 in.

Forging is where the puukko pays off. The stick tang is drawn down out of the bar instead of cut from it, so about 3 3/4 in of bar, clean-up included, becomes the whole 8 1/2 in of blade and tang. That is about 3 oz of stock for a blade that finishes near 2 oz, and three blanks from a 12 in bar. A blank under 4 in is too short to hold well in tongs, so most smiths forge it off the end of a longer bar and cut it free; set the calculator's tong hold to the bar end to count that steel. Stock removal has to cut the full 8 1/2 in profile plus clean-up and grind most of the tang's width away, so the same blade takes about 8 3/4 in and 6 oz of 1 × 5/32 in bar, two to an 18 in bar. The matching KraftyDesign blank (the "Draw this blank" link) has a straight spine with the point just below it, a long straight edge that only sweeps up near the point, and a narrow tang.

What a puukko is for

The puukko is the small general-purpose belt knife of Finland: one edge, a stick tang that runs through the handle, usually a flat spine and usually no finger guard. It is used mostly for carving, both decorative work and fire-making, and for cleaning fish and game. The flat spine is there so you can push on it with a thumb or your other hand. The traditional blade length is one palm's width, usually 90 to 120 mm (3 1/2 to 4 3/4 in), and the blade is often shorter than the handle. Carvers, hunters and leatherworkers lean toward shorter blades; carpenters toward longer ones.

The edge is a Scandi grind: a wide, flat bevel taken all the way down to the edge, and factory makers such as Mora add a micro bevel. Two Finnish smiths discussed in a BladeForums thread grind theirs at an 18 to 21° included angle. The traditional handle is curly birch (visakoivu), the most common handle material on small makers' puukkos from the 1770s into the 1900s; birch bark (tuohi) and bone are the other old materials. Birch bark keeps its grip even when wet, which is why the 19th-century Pekanpää working puukko used it. On a traditional puukko the stick tang runs through the handle, and a brass nut or cap is clamped or peened onto the end.

The form known today took shape mostly between the 1770s and the 1900s, out of older utility knives. Ostrobothnia was one of the main puukko-making regions by the mid-1800s, and a 2026 University of Oulu thesis on puukko history has the Fiskars ironworks making puukkos from the 1830s, mostly for export to Russia. The Kauhava puukko, from South Ostrobothnia, came to prominence around 1900, and by the mid-1900s, the same thesis says, nearly 90 percent of Finland's puukko factories were in Kauhava. The town still has a puukko and textile museum. In Kainuu the Tommi puukko (sturdy handle, long straight blade, red and black sheath) has been forged in Hyrynsalmi since the late 1800s. Finland's national inventory of living heritage traces it to the smith Kalle Keränen (1844 to 1912), who trained at Fiskars and came home in 1870, and says the name comes from Thomas "Tommi" Woodward of Fiskars, whose nickname passed to Keränen. The lapinleuku is a different, much bigger knife (see the FAQ below).

These claims are unconfirmed, so take them as stories rather than history. Some retailers and publishers run the puukko's line back to the Viking Age, with one Finnish retailer starting it at the end of the Vendel Period and a publisher's blurb calling it a 2,000-year-old knife; the sources above say only that it grew gradually out of prehistoric utility knives and weapons. The same retailer says Kauhava smiths made puukkos for Tsar Nicholas II. Wikipedia says the long väkipuukko ("strongknife") of old inspired the Sami leuku.

Stock for a puukko

Forged puukkos are often rhombic in section, thicker through the middle of the blade than at the spine (two posters make the point in a BladeForums thread on puukko spine thickness), so order bar for the thickest point you mean to leave, not just the spine. In BladeForums' long-running puukko thread, one poster calls 80CrV2 probably the most used steel among Finnish makers and says most harden it to 59 to 61 HRC.

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

Questions