Keeping those tools sharp
This is something easily overlooked, but an essential part of the turning process. Very dry timber can blunt a gouge in seconds, so understanding the grinding wheel is quite important.
A correctly sharpened gouge will have a perfect bevel, without any flat spots or ridges. The trick is to maintain this profile, even after countless passes over a grinding stone. I used to think that once sharpened, my gouge would be fine for a day or so! However, I soon discovered that wood has a whole load of blunting properties – dirty bark, tough knots and the odd nail or two, soon damage the cutting edge.
Just about all of my tools are sharpened using a Record 6” bench grinder. The only exception is my Rolly Munro, which I will be reviewing shortly. The grinder has a 40mm wide aluminium oxide wheel on one side – a must for sharpening a turning tool. The other wheel is made of a much coarser compound. This can be used for shaping and profiling, but is too rough for sharpening.
I always check the condition of the grinding wheels before using the machine. They can become out of balance quite regularly and need dressing with a specific tool. You can use either a dressing block, or dressing wheel – the photo shows a dressing wheel in use.
When sharpening, I position the gouge at an angle, so that the cutting tip points towards one side. This helps retain a good edge, as I roll the bevel across the wheel. The key is to align the bevel of the gouge with the face of the wheel, so that an even grind is taken off the entire surface, in one pass. However, this is easier said than done and something I have really only just mastered! Parting tools are a lot easier – just start at the heal of the tool and then grind until you can see the tip touching. Repeat this for the other side.
The gouge being sharpened...
The parting tool is a little easier...
Ready for use...
I have a water butt just outside my workshop and use it for dunking the tools in after a grinding session – I can’t say for certain if it hardens the steel, but it does make them easier to hold!
