nonstoprc

My Feedback: (90)

I found myself that I need to replace the gear set for 1 elevator and 2 split rudder 9650s on my Passport, after 1.5 season (about 150 flights in total). All three have some centering issue.

The stock 9650 gears are nylon, and I wonder if there is metal-type substitute.

The other alternative is to replace 9650s with some other choices. What elevator servos are you using?

bjr_93tz

My s9650's have done about 1.5 years of service now and I replaced the gears which tightend them back up, however the feedback pots in the servos definitely had a "loose" spot around center.

With the gear train out you could turn the ouput shaft (which is connected to the pot) and feel the loose spot right where it would usually sit for center so I know the servo is on borrowed time. Setting the subtrim one full spline off centre would regain centering accuracy (which I've done with the Rudder servo) but give it another year and I'll be looking to change them out for good, but to what I don't know??

Jason Arnold

You could replace them with the BLS153 servos. They are the same footprint as the S9650 but without the mounting tabs on the sides.

Cheers,
Jason.

nonstoprc

My Feedback: (90)

Thanks guys for the tip and suggestion.

On BLS 153, Tower [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXYAE9]here[/link] lists its replacement gear as nylon (in black). Are these gears durable?

Jason Arnold

I'm using them in my Spark without any issues.

Regards,
Jason.

PatternFlyer

My Feedback: (182)

Jason,

BLS153 has black nylon gears.

How do they hold up?

I've had a couple of new out of box S9650 with gear slop. Replaced them under warranty.
The other plane got JR DS3421.

If not Futaba or JR, Savox has 1250MG.

http://www.savoxusa.com/SearchResult...h=mini+digital

Jason Arnold

They're holding up very well. As I said, no issues. Minimal slop too.

Regards,
Jason.

cmoulder

Also for consideration, Airtronics 94761Z, same ballpark specs as Fut 9650, good speed/hold/center.

I have only 120-ish flights on them, but the gears have absolutely zero slop thus far.

Electric models are a heckuva lot easier on servos!

nonstoprc

My Feedback: (90)

Here are the specs for potential replacement servos for 9650. Seems there are more than one choice!

================
Futaba BLS-153
Control System: +Pulse Width Control
Required Pulse: 3-5 Volt Peak to Peak Square Wave
Operating Voltage: 4.8-6.0V
Operating Temperature Range: -20 to +60 Degree C
Operating Speed (4.8V): 0.15sec/60 degrees at no load
Operating Speed (6.0V): 0.12sec/60 degrees at no load
Stall Torque (4.8V): 76.4 oz/in. (5.5kg-cm)
Stall Torque (6.0V): 97.2 oz/in. (7.0kg-cm)
Motor Type: Brushless Motor
Potentiometer Drive: Indirect Drive
Bearing Type: Dual Ball Bearings
Gear Type: Metal
Connector Wire Length: 12"
Dimensions: 1.40” x .59” x 28.6” (35.5 x 15x 28.6mm)
Weight: 0.92 oz. (26g)

========================

JR DS3421 Digital Mini MG Servo
Specs
Size Category: Minis and Micros
Type: Digital
Application: High-performance aircraft when space and weight are at a premium, yet the need for precision is high.
Torque: 65 oz-in @ 4.8V; 75 oz-in @ 6V
Speed: .18 sec/60° @ 4.8V; .15 sec/60° @ 6V
Length: 1.30 in
Width: 0.58 in
Height: 1.02 in
Weight: 1.04 oz
Bushing Or Bearing: Bearing
Bearing: Dual
Motor Type: Coreless
Gear Type: Metal
Voltage: 4.8V-6.0V

===============================

JR
DS3711HV High Voltage Digital Mini Torque MG Servo
Specs
Size Category: Standard
Type: Digital
Application: Small Aircraft and Sailplanes
Torque: 86 oz-in (2S Li-Po)
Speed: .13 sec/60° (2S Li-Po)
Length

================

Savox 1250mg

This is the Savox SH-1250MG Super Torque Metal Gear Mini Digital Servo-savsh1250mg.

Features:
The coreless motor and light weight design provides smoother, faster, and more efficient operation.
The metal case design not only looks awesome but also allows for cooler and smoother operating temperatures.
Metal gears form a solid framework for precise control and operation.
Supports digital and analog control signals
Ideal for rudder on 450 level helis, CCPM on 500 level helis, and steering servo on 1/12th scale cars.
Dimensions(mm): 35.0X15.0X29.2
Weight(g): 29.6
Speed(@4.8V sec/60): .16
Torque(@4.8V oz-in): 30.6
Speed(@6.0V sec/60): .11
Torque(@6.0V oz-in): 63.9
Gear: Metal
Bearing: 2BB
Case: Aluminum
25 Tooth Spline

================

Airtronics 94761Z - Micro Digital Wing Servo

Basic Information
Modulation: Digital
Torque: 4.8V: 55.0 oz-in (3.96 kg-cm)
6.0V: 66.0 oz-in (4.75 kg-cm)
Speed: 4.8V: 0.15 sec/60°
6.0V: 0.12 sec/60°
Weight: 0.81 oz (23.0 g)
Dimensions: Length:1.06 in (26.9 mm)
Width:0.47 in (11.9 mm)
Height:1.18 in (30.0 mm)
Motor Type: 3-pole
Gear Type: Metal
Rotation/Support: Dual Bearings

Jason Arnold

Looks like the BLS153 is the best for speed, torque & weight...

Cheers,
Jason.

Lazer

My Feedback: (27)

Savox 1250mg and others of the Savox line that we sold to date have held up very well , price is good, and service is great.

(That's my two cents)[8D]

Jetdesign

My Feedback: (8)

I just got the JR DS3517 - these would be the high speed alternative. You can get plastic gears for $4 if you want them.

I had the Airtronics 94761 - very smooth and precise servo but not coreless for those of you who want coreless servos. They are also much smaller so may need some additional material to make them fit.

Specs - DS3517 MG
Size Category: Minis and Micros
Type: Digital
Application: Small Airplane and Small Helicopter Cyclic
Torque: 42 oz-in @ 4.8V, 51 oz-in @ 6V
Speed: .11 sec/60 degrees @ 4.8V, .09 sec/60 degrees @ 6V
Length: 1.02 in
Width: 0.58 in
Height: 1.30 in
Weight: 1.04 oz
Bushing Or Bearing: Bearing
Motor Type: Coreless
Connector Type: JR
Gear Type: Metal

nonstoprc

My Feedback: (90)

There is also the Futaba BLS-651 Brushless. Almost identical mounting footprint as 9650, metal gear and great torque specs @ 6v (97 ozin).

Control System: +Pulse Width Control
Required Pulse: 3-5 Volt Peak to Peak Square Wave
Operating Voltage: 4.8-6.0V
Operating Temperature Range: -20 to +60 Degree C
Operating Speed (4.8V): 0.15sec/60 degrees at no load
Operating Speed (6.0V): 0.12sec/60 degrees at no load
Stall Torque (4.8V): 76.4 oz/in. (5.5kg-cm)
Stall Torque (6.0V): 97.2oz/in. (7.0kg-cm)
Motor Type: Brushless Motor
Potentiometer Drive: Indirect Drive
Bearing Type: Dual Ball Bearings
Gear Type: Metal
Connector Wire Length: 12"
Dimensions: 1.40” x 0.59” x 1.13” (35.5 x 15 x 28.6mm)
Weight: 0.92 oz. (26g)

bondtasha

is the torque of the jr 3517 sufficient at 42 oz in

Jon Wold

My 9650s have a bit of slop around the senter. Replaced them with BLS153s and never looked back, they are super tight. Just waiting for Futaba to make a HV-edition of those. Must be just a matter of time.

PatternFlyer

My Feedback: (182)

Most run that servo at 6V. I don't have problem on those in a smaller plane, but larger surface than our 2m elevator.