Phil Irons - Diamond Grinding Wheel Review
Diamonds are a Tormek's best friend.
I have been using a Tormek 2004 almost solely to sharpen all my turning tools for the last two and a half years. Previously it was all done using a white wheel on a six inch high speed bench grinder with the help of various jigs.
One of the most frustrating things about using a Tormek to sharpen turning tools is that the standard wheel deforms quite rapidly. Turning tools create ridges and grooves and sometimes where the tool sweeps back and forth lumps, this causes the wheel to become eccentric and then needs to be trued up with a diamond truing jig which takes some time to do properly and dramatically reduces the diameter of the wheel. Even with these annoyances I still recommended the use of this wet stone grinding system for the ease with which a very sharp edge can be replicated on virtually all turning tools.
These problems are now history, last October I was asked to test a diamond coated wheel that has been designed to retro fit both Tormek models in place of the original aluminium oxide wheels. The steel wheel is 2" wide and 8" in diameter and coated with 30 micron synthetic industrial diamonds which are attached by means of a nickel plating process so that two thirds of the diamonds are buried, a bit like icebergs.
When the wheel arrived I spent about an hour sharpening every thing in site, from old carbon steel tools through to some of the highly wear resistant HSS tools that are available now, they all came of the wheel razor sharp. When I ran out of turning tools I thought "What have I got that is harder?" The answer was tungsten carbide tipped drill bits, the tips of my old Stewart System Slicer and the Stellite tips on the Woodcut bowl saver all of which are now amazingly sharp and had no effect on the wheel at all, it just sharpened them. At first the speed of sharpening is about double that of the standard wheel but this settles down as the very fine points on the diamonds are dislodged and it now cuts about 20% faster and produces a very fine edge on any tool sharpened on it.
The increase in sharpening speed doesn't make the Tormek into a mass metal removal system, so any new turning tools are ground to shape on a high speed bench grinder and then sharpened on the diamond wheel, but the beauty of using this wheel is that it will always stay flat and there is no messy sludge in the trough to be cleaned out.
The manufacturers say they conservatively estimate that their wheel will last six times longer that the standard wheel and that when it does eventually wear out it can be recoated with new diamonds. However I only use mine with the wheel running away from the edge, so in theory when it is worn out it that direction I can turn the wheel around and it should be as good as a new one, but I think that is a long way off yet.
The wheel can be run either wet or dry, but I have found that it clogs less quickly if it is run with the face just touching the water in the trough, it does not need to be submerged like a stone and at the end of the day I use a syringe {minus needle} to remove a small amount of water from the trough so that the steel wheel does not corrode, next morning I squirt the water back into the trough and I am ready to sharpen my tools.
The only instruction from the manufacturer was that it must only be cleaned with a pumice stone which removes the debris without damaging the nickel plate, so I pinched the one out of the bathroom and used that. A 6" long pumice stick is now supplied at a small additional cost with the wheel.
I am so impressed with my new wheel and their double sided credit card diamond slips and files that I have become a sales agent for the manufacturers.