Monday 9 July 2018
I am often asked why I have four different parting tools. Well, this depends on the job that I am using the parting tool for. Do you need to buy four parting tools? No, you should buy them as you need them. Buy the 3mm (1/8in) standard parting tool as your first choice. Can one parting tool do all the jobs? I would say no. My main two are the standard and thin parting tools; the diamond and fluted are the two that I use the least, but are still used regularly for jobs that may require alternative parting tools.
Standard parting tool
This is the tool I use the most. The standard parting tool will cover most jobs in the workshop. Mine is the 3mm (1/8in) wide version. The angle is 25° on both sides; I find this angle works best for me. If I am only parting a short distance into the wood – around 12mm (1/2in) or 12.5mm – I will cut this in one go. If deeper, then take a second small cut around 1mm (3/64in) wide to give clearance to the parting tool; this will prevent any snatching and reduce the heat build up.
Diamond parting tool
This is named as the end of the tool is diamond shaped.
I use the diamond style of parting tool if I am cutting a wider groove. Mine is 5mm (3/16in) wide. I can cut a lot deeper with this type than with the standard type without a clearance cut. The shape of this tool means that only a small portion of the tool is in contact with the groove sides, which will reduce the friction.
Thin blade tool
This is only 1.5mm (1/16in) wide and I use this mainly for boxes. The reason I use this one is for grain continuity: the narrower the parting tool, the less timber is removed. This tool can be used to part off a finished item when you do not have much waste timber left for the parting cut. Again, if parting a long way into the timber then take a small clearance cut, as being only thin it will get hot very quickly. Like all the parting tools it must be kept sharp, or it may not cut in a straight line.
Fluted parting tool
The last parting tool is totally different in its design. This type has a groove cut in one edge and may be used groove side down on the toolrest depending on the make. The advantage with this type is you will have smooth sides to the cut. If parting off an item, the base will be smooth compared to the other types of parting off tools. One point to bear in mind is that this type can leave very small grooves in your toolrest which will need removing to prevent other tools from catching.