Bowl gouges
Bowl gouges
EXPERT KNOWLEDGE BOWL GOUGES
Which bowl gouges to buy? How do the turning tubes differ from each other?
Bowl gouges are available in different versions. Some have a more economically produced, U-shaped inner Shape. These are more suitable for a traditional, straight bevel. The so-called superflute with a parabolic cross-section, on the other hand, is the most commonly used tube shape today. It is suitable for many types of bevelling and different tube diameters. The Ellsworth tube is a speciality among Bowl gouges, it was developed by David Ellsworth. The shape of its inside is parabolic and slightly deeper than the superflute. Its cross-section harmonises perfectly with a special ground joint that is pulled far back. This combination makes the Ellsworth tube extremely versatile and enables up to six different cutting positions.
What Bevels can a Bowl gouges have?
We offer bowl gouges in four different bevelled edges:
- The simple factory bevel has a very short cutting edge, can only be used to a limited extent and is useful, for example, when turning deep Shawls at the transition from the wall to the base. It is a short, simple basic grind that can be produced quickly in production. If you want to regrind a new tube according to your personal preferences, you usually choose this bevel.
- Even the traditional bevel is somewhat more complex and versatile. With this standard Bevel, the flanks are pulled back slightly to prevent the corners from hooking, as is the case with the factory Bevel. It is suitable for all crosscut work.
- With fingernail bevelling, the flanks are pulled far back so that the sides can also be used for cutting. The fingernail bevel is suitable, for example, for roughing cross-cut timber, for narrow profiles and for finishing with a pulling cut.
- The Ellsworth special bevel is retracted even further than the fingernail bevel and, in combination with the deep flute, enables up to six different cutting positions.
Many woodturners use up to three differently ground bowl gouges in order to optimise the bevel in each case and thus achieve the best surfaces. Crown Bowl gouges with oiled ash wood handle and ready-to-use bevel are available exclusively from DICTUM.
How can I sharpen my Bowl gouges myself?
Sharpening turning tools is a challenge, especially for beginners. In our sharpening courses, you can learn how to sharpen tools under professional guidance. Bear in mind that the hardness of the steel used for turning tools (HSS, PM and cryogenic steel) places special demands on the abrasives used. We recommend low-speed and wet sharpening systems with CBN grinding wheels, diamond grinding wheels or "Blackstone Silicon" discs for grinding turning tools. Here is a brief overview of the most important grinding types and sharpening settings for bowl gouges:
Bowl gouges with factory grinding
Grind freehand on a low-speed bench grinder (e.g. DICTUM DS 150 L) with a support table. Shift the axis of the bowl gouges by approx. 20° and rotate at the same time, ensuring symmetry during sanding.
On wet sanding systems (e.g. Tormek T8), set the universal support horizontally with TTS-100 to hole spacing A and set SVS-50 to 50° to 65° (depending on the bevel angle).
On a belt grinder (e.g. Sorby ProEdge), set the support table with V-block Sharpening jigs according to the bevel angle.
Bowl gouges with traditional bevel
Grind freehand on the slow speed Bench grinder with support table. Start on the outside and ensure symmetrical flanks.
On wet sanding systems , set the universal support horizontally with TTS-100 to hole spacing A. Set SVD-186 to position 2, clamp with 65 mm overhang (adjust according to bevel angle).
On the belt sander, with fingernail bevelling device in hole 1/position 2 and projection 58 mm (for bevel angle 50°). Adjust the height of the sanding arm to the Angle. Or freehand sanding with support table.
Bowl gouges with fingernail bevel (45° bevel angle)
On slow speed bench grinders, e.g. with Wolverine Vari Grind sharpening system, item 2 and 53 mm projection.
On wet grinding systems , set the universal support horizontally with TTS-100 to hole spacing A. Sets SVD-186 to pos. 2, protrusion 65 mm, pull flanks far back.
On the belt sander, only possible to a limited extent with ProEdge.
How long should the handle be for Bowl gouges?
The handle of a bowl gouges is usually slightly longer than that of turning tools for long wood turning (Parting tools, Roughing-out gouges, Spindle moulding gouges etc.), but shorter than that of turning tools (Ring tools, Hollowing-out gouges etc.). With a longer handle, the tube can be guided precisely during turning. However, the handle must not be too long, as the tube must be guided very dynamically by the turner in order to be able to follow the desired external and internal shape. The handle must not hinder him or bump against the lathes.
