Crawler: Savox SC-0251MG Metal Gear High Torque Servo

With the Axial AS-1 being on the (very) weak side, and niceness from James', I managed to get the Savox into my AX10. Mounting it on the chassis was fairly easy, rubber mounts and all. Haven't had a chance to test it in the real world yet (probably tommorow with Charl in Gordons Bay), but the torque is tremendous. Sweeping from left to right makes the whole chassis dip and wag. The Savox servo's are impressive, and much easier to come by around here than the HiTec's, which are a bit overpriced anyway. Full metal gears, digital, and around 16KG.cm of torque, should get me out of tight spots now, with much more ease.

Savox SC-0251 MG

Dimensions(mm): 40.7X19.6X42.4

Weight(g): 61.0

Speed(@4.8V sec/60): .20

Torque(@4.8V oz-in): 180.5

Speed(@6.0V sec/60): .18

Torque(@6.0V oz-in): 222.2

Gear: Metal

Bearing: 2BB

Case: Plastic

Running current (at no load): 300mA @ 4.8V

Running current (at no load): 350mA @ 6.0V

Stall current (at locked): 2600 mA 

Stall current (at locked): 3200 mA

Idle current (at stopped): 5 mA

Limit angle: 180° ± 10°

Connector wire gauge: ＃22 AWG

Connector wire length: 150 ± 5 mm

Horn gear spline: 25T

Control system: Pulse width modification

Amplifier type: Digital controller

Operating Travel: 120° (when1000→2000 μsec)

Neutral position: 1500 μsec

Dead band width: 5 μsec

Rotating direction: Counterclockwise (when1500→2000 μsec)

Pulse width range: 800→2200 μsec

Maximum travel: Approx 165°(when800→2200 μsec)

You will see in the photo that I still have the plastic linkages on, and a standard Axial servo horn. This will change very soon. I have an order coming in, paid and ordered ages ago, but still waiting... The steering linkage and rod will become aluminium and hopefully this will cause less slop. The composite plastic links are great, sure, and they protect against falls and servo gear strips, yes... but the lack of accuracy is a bitch.


Problem 2:
The servo obviously demands more power than the internal BEC can deliver (which is about 1 Amp in my case). Turning the servo past 50% causes a slight drop in power on the motor. James will be organizing a BEC for me in the coming week, so Ill test it out and see if that resolves the issue. Until then, I don't think it's a trainsmash.

I also put around 40gram of lead weights, evenly spaced, into each front wheel on the rim to aid COG.


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