Choosing Between White Paper and Blue Paper Steel: Does It Really Matter?

“We want steel that’s easier to handle.”

“We want to sharpen less often.”

“We want blades that last longer, even on hard timbers.”

In response to these voices from the field, Blue Paper Steel was created. Based on White Paper Steel, small amounts of alloying elements were added to compensate for its weaknesses.

Thus was born Blue Paper Steel—equipped with wear resistance and strength against heat—and it spread as a steel that could better withstand professional use.

Tungsten (W), which forms hard carbides and improves wear resistance.

Chromium (Cr), which increases resistance to tempering and provides stability against heat.

In some cases, Vanadium (V) or Molybdenum (Mo) are also included, further boosting edge retention and stability during heat treatment.

These differences in composition are what separate the character of White Paper Steel from that of Blue Paper Steel.

Blue Paper Steel excels in edge retention, and its sharpness does not easily decline even during long sessions of use. When working with hardwoods or timbers high in resin, it is able to maintain relatively stable cutting performance. It is also more resistant to tempering and offers greater stability in heat treatment, making it less dependent on the blacksmith’s skill compared to White Paper Steel.

Even today, many high-grade chisels and planes are made with Blue Paper Steel, supporting craftsmen in their daily work.

However, because of this, it is somewhat harder against whetstones, and the sharpening feel is not as light and smooth as White Paper Steel. In other words, Blue Paper Steel is best suited for a style that prioritises edge retention over ease of sharpening.

By the way, it is often referred to simply as “White Steel” or “Blue Steel.” But the correct terms are White Paper Steel (白紙鋼) and Blue Paper Steel (青紙鋼). As mentioned earlier, since the steels cannot be distinguished by appearance alone, they were wrapped at shipment in white or blue paper to identify them. Knowing this background makes it clear that the names are not just colour labels but historical names that reflect their origins.

Well then, that’s the explanation up to this point. But, Does it really help to know the difference in steel?

To be honest, I wonder whether there is really any need to know all these details. Even if beginners or amateurs were to learn the fine distinctions in steel composition, the actual benefit they would gain in their work would likely be limited.

Looking back, when I first began my apprenticeship (thirty years ago), I never once bought a tool by specifying White Paper or Blue Paper Steel. Of course, I knew the names and had a rough idea of their characteristics, but knowing that didn’t mean that a beginner like me could actually feel the difference in practice.

So when I bought tools back then, the only things I really relied on were the opinions of my master or senior carpenters, and the recommendations of a trustworthy tool dealer.

These days, however, perhaps due to the influence of social media and online articles, I feel that more and more people have become strangely fixated on whether a tool is White or Blue. To be honest, when I was first asked about it, I was bewildered—“Why are people so hung up on that?” But as the same question was put to me again and again, I began to think, “I need to be able to explain this properly in my own words.” That is the reason I researched, organised, and wrote down my thoughts in this way.

Behind this is also the marketing strategy of blacksmiths themselves. When selling blades, it is surprisingly difficult to show users differences they can immediately understand. Technical distinctions such as the precision of forge-welding or the control of quenching temperature may be clear between craftsmen, but they are not things that general customers can grasp.

In that context, the label of steel type becomes convenient. Saying “Ours is Blue Paper Steel, so it holds its edge,” or “Ours is White Paper Steel, so it has sharpness,” is simple, persuasive, and resonates intuitively even with people who lack specialist knowledge. By emphasising the difference in steel types, it can be made to appear as if the product has a clear superiority.

A blacksmith I know once put it frankly: “To be honest, the differences are small, but it’s a convenient way to explain things to customers.” In other words, the differences in steel types have functioned less as essential performance distinctions and more as “words for selling.”

As a result, the very names of steel types became established as brands. White Paper = sharpness, Blue Paper = edge retention—these images began to walk on their own, eventually being used as deciding factors in purchases. Today, more than actual steel performance, it is the names themselves that are treated as “added value.”

Another major factor is the existence of the Kezurou-kai (Planing Competition). This event, where people compete in the finish planing of wood, draws craftsmen and enthusiasts from all over the world and has attracted attention as a stage where shavings as thin as 0.01 mm are showcased. The thickness and beauty of the shavings are judged, and the event has played an important role in communicating the refinement of Japanese woodworking techniques to the world.

Its achievements have indeed been significant, becoming a chance for many younger generations and overseas woodworking enthusiasts to discover “the culture of Japanese planes.”

Yet at the same time, because of the competitive nature, attention naturally focused on “What steel was used?” or “Which blacksmith made the plane?” Conversations revolved around who achieved how thin a shaving with what tool, and this in turn became a trigger for steel types to be overemphasised.

Originally, the true value of the Kezurou-kai should have been in “spreading the culture of engaging seriously with wood.” However, in reality, among audiences and participants, discussions like “Blue Paper gives an advantage” or “Even with White Paper, you can shave this thin” became popular, and the labels of steel types came to walk independently as a kind of “evaluation standard.” I feel this trend fuelled the excessive interest in steel type differences.

Even now, I feel that users do not need to know steel types in such depth. It is true that White Paper is easier to sharpen and tends to give a keen sharpness, and that Blue Paper holds an edge longer. But those differences are not so great that they manifest as decisive distinctions when you actually stand at the workbench and cut wood. If anything, they are no more than a difference in “personality.”

What actually has far greater influence on sharpness and finish is the accuracy of sharpening, the adjustment of the blade angle, and the condition of the dai (plane body). Whatever steel you use, if your sharpening is poor the edge will dull quickly, and if your adjustments are insufficient, the wood won’t cut as you wish. On the other hand, with properly honed blades and a well-prepared dai, whether it is White Paper or Blue Paper, the tool will exhibit more than enough sharpness.

In the end, what matters most is how you engage with your tools. Rather than chasing steel names, you need to keep sharpening with your own hands and listen carefully to the voice of the blade. It is this accumulation that ultimately determines the quality of your work.