I mostly use ordinary gouges when making bowls. But I thought a ‘fluteless gouge’ might be interesting to try. I’ve watched Reed Gray’s video on YouTube, in which he recommends them for finishing cuts, in particular across the bottom. It would be possible to use carbon steel, but I decided to make a fluteless gouge as a tipped tool.
I started with a length of round mild steel bar about 16 mm (5/8″) thick. On one end I filed a step, reducing the thickness to less than half the original diameter. It was heavy going, but I used a belt sander for some of the work. I then cut a 16 mm x 30 mm piece of high speed steel from an old machine hacksaw blade. I used an angle grinder with a thin cut-off wheel. Any thin, flat bit of HSS would do. I cleaned off the surface coating from the blade and made the step to fit the cutter. Its top surface was then on the centre line of the bar.
Brazing the tip
Using a propane torch with flux and brazing metal from an Ebay supplier I fixed the tip to the bar. As an alternative to brazing, it should be possible to use epoxy glue to fix the cutting tip, specially if the tip is reasonably large and its surface roughened to hold the epoxy. Most propane torches can’t reach brazing temperature in free air, but I was using a Bullfinch torch that can achieve a higher temperature. It took a little time to melt the brazing metal. Then I just had to clean it up, removing surplus flux and brazing metal, shape and sharpen the cutting edge on the grinder and fit a handle. The edge has a gentle convex curve.
The grinding angle is quite obtuse, like a scraper, and the tool looks like a scraper, but is not used like one. Instead, its bevel rubs with the tool inclined slightly upwards. Some turners use ordinary scrapers like that, but only if the tool is turned on its side, never flat on the rest. Using either a scraper or a fluteless gouge pointing upward but with its edge horizontal is very likely to cause a severe dig-in. The fluteless gouge must be used on its side so the lower part of the edge is nearly vertical and slices through the wood. It can work in either direction. It can only take a light cut, but as the videos show, it leaves a good surface even on difficult timber. Although the grinding angle is obtuse, the wood coming onto the slicing edge sees it as very sharp.
Its cutting action is like that of a traditionally ground bowl gouge, with the wing close to the wood surface. In each case the edge is nearly vertical. But the shape of the fluteless gouge puts the shaft nearly perpendicular to the wood surface. This reduces any tendency to vibration, and it can work right up to a corner. It works well. It does not replace the gouge, it’s just a finishing tool that I sometimes use on the bowls I sell here.
After I’d used it a few times though, the cutting tip suddenly fell off. The brazing had been completely unsuccessful. Only the melted flux stuck the tip on. Because the steel bar had not been hot enough, the brazing metal did not run under the tip. The bar was too big for the torch to heat properly in free air.
To make a better job of it, I stacked a couple of insulating fire bricks, also obtainable from Ebay. They made a little hearth. This time, the cutter and the end of the bar were resting on the firebrick surface instead of being in free air. The refractory served to reduce heat loss. This was enough for the torch to quickly get them hot enough.
The brazing metal spread over both mating surfaces, ‘tinning’ them. I then put the cutter on the step and heated again until bright red hot. The brazing metal melted and the tip settled into place. I cleaned it up again and resharpened, and this time I’m confident the tip will stay put. The HSS is still too hard to file and seems unaffected by the heat. But there are different grades of steel, and to reduce the possibility of the tip softening by the heat treatment it might be best to use low temperature silver solder instead of brazing rods.
I made a handle by drilling a push fit hole for the shaft in a bit of scrap and turning to shape.