HS-985MG Question?
05-26-2012, 09:32 AM
#1
HS-985MG Question?
I just bought a brand new HS-985MG servo and I have a question. On the box it says that the servo contains a metal-karbonite gear. I have heard that karbonite gears are not good for models using gas motors. Before I purchased the 985MG I emailed Hitec customer service and they told me that the gear train on the 985MG was just as strong as the 645MG and that the 645MG also contained the same metal-karbonite gear. Is that true? I will be using this servo on the elevator of my Yellow Aircraft P-47 using a G-45 so I want to make sure the gears are strong enough for the application.
Thank you,
Tony
Thank you,
Tony
05-26-2012, 07:55 PM
#2
Senior Member
RE: HS-985MG Question?
ORIGINAL: Tony Gag Jr. I just bought a brand new HS-985MG servo and I have a question. On the box it says that the servo contains a metal-karbonite gear. I have heard that karbonite gears are not good for models using gas motors. Before I purchased the 985MG I emailed Hitec customer service and they told me that the gear train on the 985MG was just as strong as the 645MG and that the 645MG also contained the same metal-karbonite gear. Is that true? I will be using this servo on the elevator of my Yellow Aircraft P-47 using a G-45 so I want to make sure the gears are strong enough for the application. Thank you, Tony
You are quite correct in that a servo with an all Karbonite Gear Trains must not be used in petrol enginepowered models.
However, the leading servo do have at least one full or partial nylon gear in the train and reason for the presence thereof is covered under:.
. Servo - FAQ : Metal Gear Servos - Why Best MG Servo have a Plastic Primary 1st Gear
The current composite karbonite/metal gearis stronger than the original nylon primary gear.
As an aside if interested, there has justbeen a good related discussion on*************,UKand the use of the HS-645MG:
HS-635HB - is it just me or are they cr***
The HS-635HB were installed in a well oversized petrol poweredmodel, see Posts #11 onward.
. Servo - FAQ : Metal Gear Servos - DIY Repair & Extend MG Servo Gear Lifemay also assist.
. Hitec Metal Gear sets display with servo list.
Other good references are also quoted on the UK page and under the three servo sections below
"Radio Systems, Accessories, Alterations and FAQ." at:
Alan's Hobby, Model & RC FAQ Web Links
Have tried several times to upload pictures of the actual gear sets and some Futaba MG 1/4 scale sets which show that only their last two output gears were metal, but RCU keeps returning an error today.
Hitec metal gear sets displays the various types.
Alan T.
05-30-2012, 06:37 PM
#4
Senior Member
RE: HS-985MG Question?
ORIGINAL: Tony Gag Jr.Thanks for the response
but does the HS-645 use the same karbonite/metal gear or is it all metal?
but does the HS-645 use the same karbonite/metal gear or is it all metal?
also made availableunder Hitec Metal Gear sets display with servo list,
is the HS-645MGgear setshowing a nylon/metal composite gear:
http://www.hitecrcd.com/files/55303.jpg
Alan T.
05-31-2012, 11:00 AM
#6
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RE: HS-985MG Question?
Using an all Karbonite geared servo is not a good idea in gas in most cases due to vibration but ANY metal geared servo are fine. Note that the Karbonite/steel (M/K) first gear is used in all the high end servos including the 7955/50/90 which are used in giant scale, jet's military UAV's etc... and will never strip during normal usage! The 985MG is far superior to the 645MG in terms of performance so I'd stick with what you have and they will work great with no chance of stripping... unless you crash! 
Mike.
Mike.
06-22-2012, 08:01 AM
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RE: HS-985MG Question?
If it's in a gas model I definitely would, but glow or electric is it not a necessity although it certainly wouldn't hurt either!
Mike.
Mike.
