A small lightweight servo that is an upgraded version of the stalwart Towerpro MG90S digital servo but with more torque and greater speed. This little servo is perfect for aircraft, helicopters, mult-rotors, robots and other applications were you want a small, strong, fast servo. It is fitted with upgraded 6061-T6 aluminum gears and shafts and has a ballraced output.
The middle case is made of alloy which acts as a heatsink for the motor and electronics which enables them to keep cool when being worked hard. Supplied complete with a selection of 3 servo horns and mounting screws.
• High resolution
• Accurate positioning
• Fast control response
• Constant torque throughout the servo travel range
• Excellent holding power
Input Voltage: 4.8~6V
Operating Torque: firstname.lastname@example.orgV, 2.4kg@6V
Operating Speed: 0.10sec/60°@4.8V, 0.08sec/60°@6V
Normal Servo Travel: 90° (45° each way)
Case: Top & bottom plastic, alloy middle
Bearing: Double ball bearing
Gears: 6061-T6 aluminum
Gear Type: Digital
Deadband Width: 1us
Temperature Range: 0~55°C
Dimensions: 22.8 x 12.2 x 28.5mm
Output Splines: 23T (compatible with Futaba)
Servo Plug: JR type
Servo Lead Length: 250mm
1 x Towerpro MG90D Digital servo
3 x Servo horn
1 x servo horn screw
2 x servo mounting screw
Unit Weight (g):
I was very excited to receive the six MG90D servos from the Hobbyking mother-store. I purchased them on the 7th of November 2017
When they arrived I plugged them into a rx and gave them a whirl. They travelled quickly back and forth corresponding to the stick movement on my tx. They also seemed to centre ok. I packed them away for an upcoming project.
I dragged them out today to do some tests and they malfunctioned.
You see, I made up an amateur test rig and compared two servos, a Hitec HS85MG+ and the MG90D. The latter were much quicker and centred just as well - very good and consistent centre position. Then something strange happened.
I did a load test on both units (HS85 first and then MG90) and the servos jittered and then failed to respond. I thought I had burned out my servo tester and both servos. I was furious and lashed out on the MG90D, then chucked a wobbly.
Later in the day, after taking a chill-pill, I decided to take another look at the servo test, and find out what went wrong. After many hours of Hercule Poirot-like sleuthing, I got to the crux of le problé.
The home made four cell nimh battery pack that I used for the test had an intermittent fault under load. I had suspected it was flat, but it had 4.9V. The battery couldn't supply current under heavy load conditions. Put another way, the battery had died in my hands and not in an airplane so I cried tears of joy. Later, in the evening I wept mounfully because HK Au has no 2/3AA packs.
After repeating the servo test with a new 4.8V AAA battery pack, The humble MG90D came out looking very good indeed. It will now pull at least a kilo of weight (probably more, but I ran out of time).
The bottom line – Are they any good?
By comparison the $50Au Hitec is much stronger and has equivalent centring accuracy but the $6Au Tower-Pro was much faster, just as accurate or better in the centre and is still plenty strong enough for most medium sized control surfaces on an aircraft.
The tower pro now looks like very good value indeed. But will it last as long as the Hitec or a HXT900?.... Only time will tell.
Phil aka farmerjack61Muy buenos servos digitales metalicos, muy buena fuerza de torqueExcept the fact that it has a smaller spline than suspected, the servo performs very good!! I hope they will return to stock soon so i can use them for some Tricopter projects! I bought this as a replacement for the turnigy 211DMH which has almost the same performance but it comes in on less than a third of the price.Good quality, high speed