We make the axes a certain way based on research, long experience, and what really adds to the function and durability of the axe.
Thorough research and testing
Making an axe starts with the idea about what to use the axe for. I carve prototypes in wood, and then forge them in metal. I use the axe a lot, and professional carvers test continuously. Then I keep making new versions slightly different from the previous one, and continue to adjust each detail until I have reached my axe.
I make small series of the axe in cooperation with carefully selected suppliers. We make them in certain ways based on what really adds to the function and durability of the axe. Everything is made in Sweden. Together we are Kalthoff Axes.
First grade Swedish steel
We have chosen a chrome-molybdenum-vanadium steel. It’s made in Swedish Smedjebacken, at a steel mill renowned for it’s quality. When testing a number of selected steels, this steel outperformed the others.
Each alloy element affects the steel in a certain way. The modest carbon level gets us up to desired hardness, and avoids brittleness. The molybdenum increases ability to harden, increases wear resistance and reduces brittleness. The vanadium helps to get a finer grain during forging.
This combination gets us just the right hardness, high toughness and robustness, meaning that the edge bites well, and takes and holds a sharp edge for a long time.
We die forge the axes to get a high density and homogenous structure without pores or cracks. It's an old forging method where tool halves together form the shape of the axe between them. The big hammer head smashes the tools together and the blacksmith works the white hot steel from tool to tool until it has the right shape.
This way we get great control of working in the right temperatures, which allows us to not compromise our choice of steel. We can forge in our first choice steel rather than using a lower alloyed steel.
In addition, forging in one heat makes the hardening more precise because the carbon content is not reduced from numerous reheats.
Special heat treatment
Hardening is the most important aspect of the axe. Our hardening technique is carefully developed to ensure that the edge will take and hold a very fine edge for a long time and that the axe head will withstand a lot of abuse. This keen method is more time consuming and costly, but definitely worth the effort. In our tests, this edge lasts remarkably longer. The tests are done in dry pine knots with edge angle at 27 degrees.
Strong and flexing ash
We are using Swedish native wood for it's good properties as axe handle material, and to cherish the long and rich history of Swedish axe culture. The idea is to get raw materials as close as possible, and not cross the stream to get water.
Ash is our favorite because it is hard and tough to endure a bad hit, but also elastic enough to flex and pick up vibrations to protect the hands from the strike. It is traditionally used for axe handles in southern Sweden. The ash we use grows in northern Skåne. The color of the wood is bright in the sapwood and darker brown in the heartwood. The grain is clearly visible making it very beautiful.
Fitting and securing the handle
We make handles by turning and hand shaving, then oiling with raw linseed oil.
The shafting is done with great care. Both handle and wood wedge are fitted furniture dry to be as contracted as possible. We secure the wedge with wood glue. We do not use steel wedge, since it does not effect the durability or performance of the axe, only making rehandling more difficult.
Vegetable tanned leather
The hides, selected premium quality, are a by-product from local meat farmers in Uppland. The leather is vegetably tanned using only bark and water.