Six Generations of Serious Horsepower

Radio Control Car Action, Apr 2004 by Pond, Steve

Trinity D6

Trinity's D-series racing motors started with the D1-better known as the "Dirtinator " and named after world champion driver Brian Kinwald. Though originally developed for off-road, the D-series motors have been evolved to suit vehicles in every class of electric racing.

Each generation of the D motor has its own "personality" and excels in a certain racing class; but that's typical of all motors. This D6 includes a few new performance features, so we strapped it to our dyno to see exactly what it brings to the table.

The D-series racing motors are at the top of Trinity's motor line. The important distinction that makes these Trinity's best motors is the extra tuning and technology and the high-quality materials used into their construction; they may look similar to other motors, but the details distinguish them. D-series motors are used in high-stakes electric competitions at national and world-champion levels, so these are the motors that will give you the most horsepower.

D6 MODIFIED

FEATURES

Large copper brush hoods for increased efficiency.

All capacitors are factory installed.

Double-shunt, large, serrated brushes.

Polarized, color-coded brush-shunt heat sinks.

Skewed armature laminations.

Split-magnet design uses four smaller magnets instead of two.

ENDBELL. Relatively big brush-hood heat sinks distinguish the D6's endbell. The heat sinks are "polarized," which is a fancy way of saying that a black one is installed in the negative side of the endbell and a red one in the positive side. This makes it easier to identify the proper side of the endbell, which is useful when you solder the leads from your speed control to the motor. The heat sinks extend past the top of the brush hood; this interferes slightly with the installation and removal of the brush springs. The brush hoods and primary heat sinks are copper, so they're electrically more efficient than the aluminum ones commonly used. Copper is a little softer and easier to bend than aluminum, so you may have to straighten out the wire tabs if another car nails you in the endbell.

A printed circuit board sits atop the endbell and has three installed capacitors. The capacitors are recommended by most ESC and radio manufacturers to prevent interference, but the D6 comes with them already installed.

ARMATURE. The new "F" armature with a full web and crown has skewed laminations; this means the laminations twist slightly as they're stacked on the armature shaft. According to Trinity, this further reduces cogging at low speeds, smoothes out the low-speed throttle response and increases peak motor rpm.

The D6 is available in a wide variety of winds, but most notable is the flat-wire wind. Most other major brands of motor have round armature wire. Flat wire was first used in the Trinity D5 Flatliner motor, and according to Trinity, the flat wire "... saturates the armature laminations to a greater degree than is possible with round wire. The result is a more powerful, more efficient armature than one with the same number of turns of round wire." The result is a flat-wire 10-turn motor that runs like a 9-turn round-wire motor. The flat wire is stacked more closely to the armature, and that makes it easier for the motor to spool up quickly.

MOTOR CAN. A greenish platinum finish coats the D6's can; apart from that, it looks the same as the D5's. There are two small vents on each side of the can plus eight vents in the bottom. The vents in the bottom extend all the way to the can's outside diameter, so even though the motor is mounted on a flat surface, the bottom vents can still "breathe."

Inside the can is where the D6 differs from any previous "D" mill. It has split magnets, so instead of two big magnets, there are four smaller ones. Split magnets were first used in slot cars and then introduced to modern RC mills by Reedy Modifieds; they reduce cogging and increase peak rpm more effectively than two magnets. The D-6's split magnets are positioned similarly to how they would be installed in the two-magnet setup, but thin shims separate the magnets.

BRUSHES. The D6 brushes were originally developed for the P-94 motor. They're just a hair taller and quite a bit wider than a standard brush. It was determined that these larger brushes provide the ideal contact area on a commutator of standard size. The P-94 brush cross-section is about 25 percent larger than on a standard brush. The larger brush contact area spreads the current that flows through the motor across a larger area; this is more efficient and reduces brush and comm wear. The double-shunt brushes also help to carry more current than a single-shunt brush.

AVAILABLE BRUSHES

* RC4379E: high silver content; best for 4-cell applications.

* RC4380E: hard copper; good for low-turn motors and long comm life.

* RC4383E: silver; most power for 6-cell applications.

BRUSH SPRINGS. The D6 uses Trinity's conventional purple brush springs; they are classified as "heavy" and are one step below the "extra-heavy" silver springs. They rest in a slot cut between the two brush shunts and firmly press the brushes against the comm.