Keeping your tools sharp is as important as a good carving technique. Using dull tools will make our job harder and unsafe. In this article you will learn the basic concepts of sharpening for spoon carving tools.
It’s advisable to sharpen all the tools yourself and take the time to learn to do it for various reasons:
- They are special tools that need a specific edge and common knife sharpeners tend to damage the steel and take years off our knives life.
- Common sharpeners use belt sanders that leave convex edges, ruining the proper geometry of our knives.
- We need to sharpen or strop while we carve, we can’t want for someone else to do it for use, it’s part of the carving process.
- It’s an essential part of Spoon Carving so it must be considered like one more technique we must learn.
The next sketch illustrates the edge theory wich is basically making two faces intersect at one point: the edge. The more precise that intersection is the sharper our edge will be.
Having understood that basic theory, to sharpen we must remove steel from the edges of our tool to re establish that intersection.
To sharpen the axe we need wet and dry sanding paper in different grits (800, 1200, 2500 approximately), blocks od MDF at least 18mm thick and double sided tape.
The technique is maintaining a consistent angle following the edge original geometry to remove steel from both sides. Starting with the lower, coarser grit and moving up to the highest grit to polish the steel. Finally we use a leather strop for a final mirror finish.
In the next video by Robin Wood you can see the entire process:
The Straight Knife
To sharpen the straight knife we use the same method but instead of moving the block over the tool like we do with the axe, we move the tool over a block that must be secured on a surface.
This block must be as solid and flat as possible. For that purpose you can attach a piece of float glass hardwood block. The block can me approximately 20cm long by 5cm wide and 5cm tall.
We can use a non slip mat at the bottom to keep it from moving.
This way we can slide the knife over over the block on both it’s edges, using our fingers to help us register the correct angle on the block and making sure we are removing steel along the whole edge surface.
We must remove steel until we feel a “burr” along the edge. The burr is a wire edge created by removing steel evenly along the tool’s edges.
In the next video we can see Tom Scandian of Spoon Carving with Tom explaining this technique in detail:
Depending on the condition of the edge we will have to use one or more different grits of sanding paper. If we only need to a light sharpen we can pass it directly through the strop using polishing compound.
The Hook Knife
With the Hook Knife we do the same but to adapt to the curvature we use a wooden rod to hold the sand paper.
Depending on the specific Hook Knife design we will remove steel ONLY on one side untill we create a burr, then on the opposite side just use a strop or very fine sanding paper to remove it and polish.
To make the strop for the hook knife we can attach a piece of leather to a rod and use the same motion.
In the next video, also from Tom Scandian, he explains this technique in detail:
How do we know we are removing steel correctly?
When we are removing steel it is very important to check if we are doing it in the correct angle and in the right area where is needed, if not we will be wasting steel and effort.
The life span of our tools will be greater if we manage to remove as little steel as possible every time we sharpen.
To accomplish this we have to make sure the edges of our tools are registering the surface of the abrasive and we are following the correct angle to avoid creating secondary bevels.
One way of checking is using permanent marker on the edge of the tool. That way we will know more clearly where the steel is being removed and if we are using the correct angle.