nomi japanese chisels

Japanese Nomi (Chisel) (鑿, のみ)

What is a Nomi Chisel ?

The Nomi is a Japanese tool that western woodworkers would call a chisel. The Japanese chisel is not the same in every way as a western chisel. Like western chisels, the Nomi is made in many patterns to suit different woodworking tasks.

A Nomi is a type of Japanese chisel. They are typically made of high-quality steel and are known for their sharpness and durability. They are often used in traditional Japanese woodworking and carpentry. Whether a Nomi is better than a Western chisel depends on the specific application and the user’s personal preferences. Some people prefer the precision and sharpness of Japanese chisels, while others prefer the heft and durability of Western chisels. It is worth noting that Nomi chisels are more delicate and require more skill to sharpen and maintain compared to Western chisels.

Japanese 'Chisel' or nomi (鑿, のみ)

For almost every task you would use a chisel in the west the Nomi is also used in the East. The joints and projects may be different but the basic purpose of a chisel is to peel or chip away wood. Buy on Amazon a Japanese Nomi Chisel: SHINTARO Authentic Japanese Chisel (1, 18mm,0.7in)

What is Different About the Japanese Chisel?

We already know the Nomi and western chisels have similarities but those are only superficial. The Japanese chisel has a number of differences such as:

  1. Blue or White Steel
  2. Hollow ground back
  3. Blade length
  4. Bevels angles
  5. Sharpening

Traditionally the Japanese chisel is made from low-carbon steel stock. Because this steel is softer than High-Speed Steel or Chrome Vanadium it can absorb shock better.

Chisel Angles

2 Pieces Stainless Steel Bevel Gauge Axe Angle Gauge Round Shape Knife Angle Finder Knife Blade Angle Gauge 15-120 Degree for Measuring Knife Angle

  1. 30° is good for softwood carpentry
  2. 35° is considered good for hardwoods such as Oak 

In comparison to the western chisel, sharpening angles the Japanese chisel or Nomi has a less acute angle for instance I sharpen my European chisels to 28° and 30° retrospectively.

Digital Angle Finder for More Accuracy

Digital Electronic Level and Angle Gauge, Angle Finder with Bubble Level and Magnetic Base, High Contrast Display. I have this exact model and it makes the job of setting the correct angle really easy

But you may ask why is Japanese tool steel so hard. 

Japanese steel is case-hardened with Carbon at the cutting edge and tempered. White paper steel contains about 1.22% it is still mainly basic IRON.

Japanese tool steel is known for its high quality and durability, making it ideal for Nomi chisels. The steel is characterized by its high carbon content, which provides excellent hardness and edge retention, and its ability to be sharpened to a very fine edge. Additionally, Japanese tool steel is often manufactured using traditional techniques that result in a consistent and homogeneous microstructure, contributing to its overall performance.

Is Japanese Steel Brittle?

I  own several Nomi tools and they are Brittle at the edge. Although they do sharpen to a very keen edge I do have to be careful not to damage it. 

KAKURI Honing Guide

Sharpening blade is essential to maximize the performance of chisels, and KAKURI’s honing guide is designed so that even beginners can easily perform expert sharpening. Buy on Amazon 

Japanese chisel sharpening

Sharpening hollow-backed Japanese chisels must not be done in the same way as the Western chisel. The hollow back must be considered because you can over-grind and damage your chisel by removing too much of the cutting edge.

Flatten Your Back

Before you touch your cutting edge you must first flatten the back of your chisel. Using just a perfectly flat steel place the back of the chisel down and make repeated strokes.

Ideal Tool to Flatten Tool Back

DFM Diamond Lapping Plates are engineered to offer precision flatness for your sharpening stones and blades. The diamond crystal is selected to have a balance of wear and cutting characteristics.  

Polish Your Chisel

Inspect the chisel and you will see polished and unpolished areas. If the back is not polished all over the contact area the back of your chisel still needs flattening.

Estwing peening

ESTWING Ball-Peen Hammer – 12 oz Metalworking Tool with Forged Steel… Is the Ideal Tool to peen your chisel edges back into shape but you will also need a small anvil.   Made in the USA using the finest American tool steel.

Because you do not want to remove excess material the cutting edge might need dressing. To dress the edge first you have to peen the edge. Using a small anvil and a small peening hammer lightly strike the back edge of the bevel so as to manipulate the tool steel of the chisel. Basically this will slowly bend the steel so that the edge is in line with the back of the chisel.

You need a Anvil for Peening

VEVOR Cast Iron Anvil, 88 Lbs(40kg) Single Horn Anvil with Large Countertop and Stable Base, High Hardness Rugged Round Horn Anvil Blacksmith ideal for peening your Japanese chisels and plane irons.

Once the back is Flat

You can now sharpen the chisel, but wait don’t just grab your oil stone! An oil stone is no good for sharpening Japanese tool steel. You must use Waterstones for sharpening any Japanese tool steel such as the Nomi. 

Sharpen Japanese Tools with a Whetstone

The wet stone sharpening kit is made of top 100% white corundum, with 3 pieces of extra-large and thicker single-sided whetstone. 8.62″L x 3.52″W x 0.93″H Buy on Amazon

 

The best way to sharpen a Japanese tool steel nomi chisel is to use a combination of waterstones or oil stones and honing guides. Start with a coarse grit to remove any nicks or dull edges, then progress to finer grits to polish and refine the edge. Maintain a consistent angle while sharpening and test the edge regularly to ensure it is sharp and meets your desired sharpness level.

The Steel Ferrule

Unlike most common European chisels the Nomi has a steel ferrule fitted. 

What is the steel Ferrule for? The steel ferrule fitted to a chisel prevents the chisel handle from splitting. You should impact your chisel with a mallet but it is not unusual to see a chisel impacted with a hammer or a Japanese Genno. 

The Genno will damage the handle of a Nomi and the handle above the ferrule will mushroom. You can easily repair the impact area by 

  1. tap the ferrule or ring further down the handle.
  2. Soak the handle in Water
  3. Peen the end of the handle to secure the ferrule

Japanese Chisel Brands

These are the more recognised brand names for Japanese chisels

  1. Koyamaichi:
  2. Tasai
  3. Kunikei
  4. Kakuri
  5. Fujikawa
  6. Shintaro

There are many more tool makers of the Nomi but the above is widely renowned for different reasons. More obscure manufacturers make tools which are designed for a particular purpose. 

Our Recommended Western Chisels

Narex 853600 5 Piece Boxed Set of Richter Extra Bevel Edge Chisel (1/4, 3/8, 1/2, 3/4 and 1 inch)

Is a Japanese tool better than a Western tool?

I wouldn’t say that one is better than the other but that Japanese chisels are just different. They require different techniques in use and sharpening. Great for different projects in different cultures but also great for finding one’s soul. Amazon links on this page pay a small commission. 

Conclusion

Choosing a Japanese nomi chisel over a Western or European pattern of woodworking chisel depends on personal preference and the type of work being performed. I like to use both types of chisel Japanese and Western European patterns. My choice of chisel depends on the job at hand because Western or Japanese are good for different tasks.  Japanese nomi chisels are known for their thin blades, allowing for precise cuts and easy access to tight spaces. They also have a longer handle-to-blade ratio, providing more leverage and control. On the other hand, Western and European chisels typically have thicker blades and a shorter handle-to-blade ratio, making them more suitable for heavy duty tasks. Ultimately, the choice between Japanese nomi and Western/European chisels will depend on the specific needs of the user and the type of work being performed.