What the Beginner and the Novice Should Know About The Bent Knife Carving Tools
Carving Tool History:
Through some research I have found out some interesting facts about the start of the carving tools. The tools started out very primitive. They were made of jade, obsidian, bone, seashells and beavers hind leg. Certain fish shins were used for sanding. Stories have been told of people coming to the Americas northwest coast from different parts of the world, pre 1700 century. There were reports of people boating over from Hawaii, Japan and Russia. These are the people that introduced steel to the Native Americans. Also steel had been retrieved from floating debris from wrecked ships. This steel would have been in a very primitive state but a big improvement over the bone and tools. The proof of this is that the carvings started to get bigger and more detailed. The oldest bent knife I have seen was one that belonged to Wayne Carlick who said it belonged to his grandfather. The blade was made of bone and shaped in a slow curved. It was lashed with sinew to an arbutus brand that was the handle. Wayne is a carver at the Capilano Suspension bridge in North Vancouver, BC
A good quality tool will be one of the most important investments you can make as a carver. A good tool can be just as important as the experience you gain. It is very discouraging to have a tool that won’t stay sharp or a tool that is too hard to sharpen and will quite often chip or break. A good way to find good tools is to ask a master carver. They have usually established a working relationship with a retailer or a knife maker.
When looking for a carving tool ask the retailer or knife maker a few questions like what is the blade hardness and what kind of steel are they made from. If the retailer can’t tell you what kind of steel it is made of stay away from it. The hardness should be RC 57+ and the steel should be tool steel. L6 is about the best I have found for wood carving tools. The cutting edge stays sharp for a long time and there is a bit of flex in the blade. With the right heat treatment this blade has what is called a tough edge. There will be an explanation further on.
When purchasing a tools get one that has been pre-sharpened .You don’t want to sit for hours sharpening to save maybe a few dollars. If the knife comes with a guarantee you can be assured it has some quality . This will be a commitment to the carver that this is a quality tool.
Carving Tool Steel:
The composition of the steel is one of the things that makes or breaks a quality carving tool. The main function of a carving tool is to cut with the least resistance. To do this two things have to be considered, the thickness of the blade and the ability of the blade to stay sharp. The best steel for carving tools is tools steel. There are different grades of tools steel. The best is the one with the high nickel and high carbon content, preferably L6. Stay away from the tool steel that has a high content of carbide, Carbide can make a tool very hard but with a thin edge the is no material to support it and it will chip under a bit of stress. When it chips you have to have it repaired. A good tool steel will be made up of the following composition: .75% carbon, 2.60% nickel the high carbon and high nickel content gives the blade a tough edge.
Analysis of the L6 tool steel is .75% carbon, .25% silicon, .42% manganese, .025% potassium, .011% sulfur, .03%chrome, 2.60% nickel.
Straight Single Edge Knife:
There are many of these type of knifes. The ones we are most concerned about are the chip knife, the skew knife, a traditional straight edge. These blades can be different widths and lengths.
Drop point: This knife is favored by many carvers because it require a lot less wrist reaction then the ordinary straight back blade. To be effective the blade should be thin to offer little resistance while going through the wood. The top of the blade should lean forward so the knife will be doing a slicing motion while going through the wood.
Chip carving knife: You can identified this knife by the straight cutting edge leading to point. The back or spine of the blade has a curve leading down to the cutting edge. This knife is excellent for “V” cuts or any line cuts. While making the cuts you can hold the knife perpendicular to the work piece making easy on the wrist. You can use your thumb on the back to guide it while making a cut. This knife should lean forward so the knife is doing a slicing motion while going through the wood. While making tight circle cuts this knife should do very little if any chattering on the wood.
Skew knife: This knife can be identified by the 45% angle on the cutting edge. Usually this knife blade is very slender a can make very deep cuts. It is very good for “V” cuts because of the depth you can go into the wood with it being so slender. This is an excellent knife on the straight cuts. Because of the width of the blade it is not good on tight curves.
The bent knives usually have a cutting sharp cutting edge on either side. Some carvers prefer having the knife sharp only on one side because they like to push one side with there thumb and that would be a safety hazard if both sides were sharp.
These blades can be different widths and lengths. What will determine the size is the size of the carving that is being done. The blades I have made are from 3/16” to 1 ½” wide by ¾” to 6” long.
There are basically four different bent knives and all the other knives are a variation of these four.
A. Straight double edge knife :-
Although this blade is not bent it is the same shape and used to complete a bent knife set of six knives. This knife is used for clean up and detail work. While selecting this knife it will be important to make sure the blade is sharpened from close to the handle to the tip of the blade. All though it is not bent it is of the same design. It will be used for the hard to reach areas and tight corners. This blade can also be used for cutting lines
B. Slow curve knife :-
This is also known as the planer blade. At the front of this blade there will have a slight bend. There are different variations to the bend in the slow curved blade. There can be a bend from about 5 degrees to 30 degrees bend. This blade should be sharp along the level part of the blade to the tip. Some of the cuts you will be requiring from this knife will be against the stop cuts. This will require the use of the very tip of the blade. The selection of this bend will depend where the carver wants to carve. This knife can be used to level off the flatter part of the carving. It can be used for shallow cuts
C. High curved knife :-
This blade has a serious bend in it. It will usually be bent from about 45 % to 90% with a large curve. This blade should be usable, meaning sharp, from the heel right to the tip. With this knife you will be able to get into deeper areas. This knife will usually have a bit of a flat area and this can be used for leveling cuts you have made with a knife that has an aggressive bend like the hook knife. The wide curve of this blade can be used for cleaning these same cuts in a rounded area, for example, in a bowel or spoon.