Re grinding turning tools
I have just purchased my first turning tools. I am working my way through learning to use each tool in a way which mirrors the skill building which trained turners would be expected to develop. My emphasis is on skills, not projects. I am starting with spindle turning so I have purchased a couple of roughing gouges, a 25 mm oval skew, 10 mm spindle gouge and two parting tools, 3 mm and 6 mm, basically everything you need to accomplish many different spindles. Competent turning is done in large part off the cutting tools so, sharpening is really vital. Wood turning chisels are really expensive, I made a small saving purchasing two used roughing gouges. The bevels were wrong and misshapen too, so I am regrinding the profiles and the correct 45 degree bevels. As with any blade which requires significant regrinding, the first job is to grind the blade to the correct shape, blunt at 90 degrees. This makes it less likely that the metal will overheat at the thin metal at the edge and it is much easier to shape and establish bevels in two processes. You can see in the pictures the small roughing gouge still has a small portion of the incorrect bevel left. I could continue removing metal, however, there is sufficient corrected bevel to receive an edge, to rub the bevel and to register the correct angle for grinding. Each subsequent grind will correct that bevel in timely fashion. The large roughing gouge was a mess, the sides of the gouge projected further forward than the centre of the blade. It was a wave shaped 35 degree bevel, you can see from the photo just how much metal I have had to remove to correct the profile. Over the next few days I will gradually re establish the correct bevel. Due to the shape of the discrepancy I will get a perfect initial grind on this one. Every blade I own has gone through this process immediately upon arrival ( you can say goodbye to ever having sharp tools if you procrastinate at this juncture ) be they chisels, plane blades, saws, knives etc, there are no exceptions. Once prepared, a blade requires minimal regular maintenance. From a woodworkers perspective, sharpening is like money in the bank.
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