Tools of the Trade: Micro and Flex Shaft Motors
November 1, 2011 9 Comments
In order to make the burrs cut, it is necessary to install them in a variable speed, rotating motor of some kind. The burr is fastened into the motor using either a collet or a chuck system. I prefer the collet system since it holds the burr more securely and allows for a truer rotation. However the collet system can be more expensive and requires a bit more set up time when changing between burrs of different shaft diameters. Handpieces can be air driven, but I prefer the electrically powered, motor-driven models since there is no need for a compressor.
The most familiar rotating motor tool is the Dremel. It is small, cheap and usually comes with a variety of accessories useful for accomplishing any number of useful household chores. Some carvers use the Dremel as it comes, simply inserting the various burrs into the motor itself. While this works, it is not necessarily the most manoeuvrable solution and carving intricate patterns or accomplishing fine detail can prove difficult.
For an additional sum, the purchase of a Dremel Flexible Shaft can solve this problem. The burr is inserted into the handpiece on the end of the flexible shaft, which, in turn is attached to the motor. The motor is hung or mounted close to the carving, allowing the carver to manipulate the handpiece like a pencil or pen allowing for much greater control.
For beginner carvers, I would recommend the purchase of a Dremel, Flexible Shaft and few good burrs. The Dremel can accommodate burrs with shafts up to 1/8″. Downside of the Dremel is the quality of the machining in the handpiece. This results in a noticeable vibration which will reduce the ability to create fine detail since the burr will wobble slightly. Over an extended carving session, the vibration will cause your hands to go white and numb, also not pleasant.
I still have my first Dremel, and though I no longer use it for carving, it is very effective when performing sanding or polishing tasks which require torque but little precision.
The next motor a carver usually invests in is a Foredom. The Foredom is a powerful flexible shaft motor. It comes in a variety of configurations, but for carving the most useful Foredom is the S Series with a standard collet handpiece and foot pedal for controlling the speed. The Foredom S Series uses a 1/4 HP motor and is wonderful for roughing out a carving but is less useful for creating detail, since the large flexible shaft and handpiece are not easy to manipulate with finesse. The handpiece accommodates burrs with shaft diameters up to 1/4″.
Burrs of this size can remove a lot of material fast and need to be used with care. Burrs can ‘run away’ in certain circumstances, for example when they catch the grain of the antler, and can cause injury if they contact your unprotected hand or body. Always wear protection. Safe carving should be your motto! I sank a large burr into my thigh in an instant before I learned that a protective apron (leather preferred) is a must. I’ll cover safety equipment in my next post.
In order to create stunning detail in a carving, the preferred tool is the micro-motor. The motor is small, as the name suggests and resides in the handpiece itself. The handpiece is wired to a control box, which controls the speed and direction of the rotation. Like the Dremel, these handpieces can accommodate burrs up to 1/8″ in shaft diameter. Unlike the Dremel, the micro-motor tool is a precision instrument, finely machined with no wobble and negligible vibration, making them a joy to use.
The king of micro-motor tools is the NSK Electer E-Max. NSK also makes dental grinders, so they know what they’re doing. Other companies, such as RAM, make lower end micro-motor tools which still work exceptionally well, but are a little bulkier and less pleasing to work with compared to the NSK. If you plan to take up carving in a serious way, invest in an NSK if at all possible. It will return your investment both in sheer carving pleasure and in results that will most truly reflect your skill as a carver.
I’ll go into greater detail about each of these tools and cover basic maintenance concerns in a future post. Happy carving!