- The wheels
- Change a wheel
- Dress the wheel
- The installation of the drum
- Use a drum
- Shape metal parts
- Plane irons, scissors, carving and turning gouges
- Mixed spinner
- Finishing accessories
- Stolen and semi-stolen
- Make your sharpening stand
- More sophisticated devices
- Turret equipped with jigs
- Guides for irons
- Safety: watch out for the eyes
Machine of great simplicity, the drum is almost indispensable for who must maintain sharp tools. Almost all DIYers!
In its simplest form, the grinding drum boils down to a motor with two shaft outlets placed on a base, each outlet carrying a wheel enclosed in a protective casing equipped with a tool holder and a screen. A slightly more complex version includes a speed reducer, allowing one of the wheels to turn slowly in a water tank. The most sophisticated models can receive many templates facilitating the complex sharpening of tools such as gouges turning, but also that of household accessories. The majority of these devices, including the latest, are now mass-produced in Asia. But beware of the quality!
For occasional use, a 125 mm wheel model is sufficient, provided that those with a power of less than 250 W are avoided: they "block" at the slightest stress. For a more intense use, opt for a model with grinding wheels of 150, even 200 or 250 mm, whose engines are more consequent.
Like abrasives, grinding wheels exist in different grains. These original liveries are often useful for shaping the metal especially in the first prices. They are too rustic for sharpening.
- The white grinding wheels (grinding wheels) are much better suited for sharpening, although a bit soft for high speed steel.
- The green wheels, very hard, allow the maintenance of carbide tools. Gray grinding wheels (identical to those used in most basic reels) and white grinding wheels are sold in most DIY stores. Greens more rarely.
- If the diameter of the wheel hole and the drum shaft do not coincide, adapter rings available at the DIY store should be used. To get grindstones other than those sold in a DIY store, it is best to go locally to the professional trade, or mail order specialists.
Change a wheel
Changing a wheel is easy: after removal of the side casing, simply unscrew the bolt from the shaft to extract the wheel and its flanges. Attention: on the left side, the thread is reversed!
Dress the wheel
When installing or in case of irregular wear, set the wheel. Use the specific tool guided against the tool holder to give it a surface parallel to the axis of rotation.
The installation of the drum
The ideal fixed installation space saving: the drum can be bolted to a board anchored to the wall by two brackets. Prior to this, height calibration tests are recommended to determine the most comfortable working position. If there is not enough space, the drum supports an intermittent installation. In service, its support is clamped by a pair of clamps. Or, better, immobilized in the bench press by a cleat screwed under the board.
Use a drum
The main uses of the drum are the shaping of metals and the sharpening of tools. The shaping allows in particular to work the songs of the raw cutting sheets. It is better to avoid working with aluminum, copper and soft alloys: they clog the wheel. If it is not possible to do otherwise, surface dressing of the grinding wheel is then almost inevitable. The two-wheel fast drum is a simple roughing tool for use in sharpening.
You must constantly be careful not to soak the metal by overheating it. If wood turning tools can be used as rough grinders, scissors, gouges and plane irons can not be satisfied. Mixed drums that combine a high-speed grinding wheel (2,800 rpm) and a slow-moving grinding wheel (100 to 120 rpm) significantly improve the situation (although fine-grinding is necessary), with strong reserve on the quality of the grinding wheels of first prices. On the other hand, there is no need for a water grinder to sharpen metalworking tools. It is sufficient that the cutting angle is strictly adjusted and that the tool is guided preferably with a template.
Shape metal parts
The drum makes it possible to shape or rectify small pieces of metal while avoiding the work with lime, a delicate art that the apprentice fitters once spent hours learning.
Plane irons, scissors, carving and turning gouges
The shaping of plane irons and scissors is easy on a drum equipped with a suitable grinding wheel. The gouges of sculpture and filming require more control.
The dry mill / water mill combination drum is better suited for sharpening than two dry mills. It is easily for a little more expensive; it is better to replace the original wheels.
The drum can receive brushes (metal or other), and polishing and polishing felts. These accessories make it easy to finish metals and polish small pieces of varnished wood.
Stolen and semi-stolen
An experienced professional can sharpen on the fly without a tool holder. For others, work on a semi-volley, with a fulcrum, is much more accessible, even if it requires a little training. For machining metal parts, a larger work surface than the original tool holder is often convenient.
The toolholders equipping the drums are often too small and too soft. at the expense of sharpening precision. And the tilt adjustment is often random.
Drums with this defect can receive an independent tool holder once properly positioned, all will be more accurate than the original one. there are more or less sophisticated and expensive.
Make your sharpening stand
Economic alternative: make your own sharpening support. The most skilled will know how to make metal, but a plywood manufacturing can suffice.
More sophisticated devices
For those who are reluctant to learn, some manufacturers have developed a wide range of guides and templates to sharpen precisely and without specific control all kinds of tools, and household accessories such as knives and scissors (in particular, the Swedish Tormek, pioneer of the field today frequently plagiarized). The base is a slow drum combining a high quality water wheel and a leather to be rotated. With such equipment (alas, expensive) wood scissors and plane irons can almost do without stone finishing.
Turret equipped with jigs
With a drum equipped with templates, sharpening becomes child's play. Counterpart: these devices do not allow more to learn to sharpen than the stabilizing wheels to ride a bike!
Guides for irons
The "Rabo-Dew" and Spindle Guides make these sophisticated reels the ideal complement to a more precise wood-type combo, and periodic professional sharpening is still needed.
Safety: watch out for the eyes
The drum is not dangerous as long as the wheels remain protected in their casings: without them, a bursting of grinding wheel - fortunately very rare - would be fraught with consequences. But the eyes must be protected from sparks resulting from grinding. In the same way the glasses of sight: the tiny drops of molten metal are irretrievably melted in the glasses. Wearing safety glasses in addition to the protective screen is not a luxury, especially since the latter ends up opaque, which encourages to remove it. Wearing gloves to machine small, often sharp metal pieces is also recommended.