Ian R

Hi Guys

Firstly Merry Christmas

I would normally go for metal gear digi's for tailrons on 120 size jets, but the new gear train from Multiplex called Karbonite claims less wear than metal but stronger than normal resin.

As I said I would normally go for metal but if karbonites provide better slop free wear, in particular stability in heat (why I think the metal gears have some play, expansion) they seem to be an option.

Any one got any experience or opinion

Thanks Ian

SJN

Metal [sm=thumbup.gif]

Karbonite [sm=thumbdown.gif]

maverick2005

Hi Ian,

Iv,e heard quite a bit about karbonite gear box,s.
As you say there is reduced backlash between the gear train,plus retaining the strength
of the metal gearbox.plus less wear.
I have not used any yet but will consider them for my next jet.
I hope we get some feed back on them.

Kelly W

My Feedback: (2)

I'm normally a fan of Hitec stuff, but stay away from Karbonites...

I fly for the local university in the SAE Aero Design competition. They design R/C aircraft to be as light as possible and lift as much payload as possible. Our last plane weighed 9.6lb and carried 48.9 lb of lead in its winning flight. We chose a few Karbonite gears last year due to some impressive torque numbers vs. their weight. I had also considered using them in a jet that I was building at the time. I then came across a few threads on RCU essentially stating that Hitec is now recommending that they not be used in larger aircraft due to lack of strength in the gear train. If that's the case, the full torque spec isn't really realistic and the servos are no more useful than that of a slightly more powerful standard BB servo...

Needless to say, we switched them out for metal gears prior to our 1st test flight and left them in the box. Based on what I read, I'd never consider them for a jet, particularly since the backlash in the Hitec MG's is typically very good... Their best jet quality servo IMO is the 5945MG.

Kelly

HarryC

My Feedback: (1)

Karbonite is Hitec, that means it is a Hitec servo masquerading as Multiplex. All the latest design Multiplex servos appear to be Hitec badged as Multiplex. The same man owns both firms. If you are happy to put Hitec in your jet that's up to you. The original Multiplex digi servos such as the Profi and Royal are still genuine Multiplex.

H

Ian R

Thanks guys

I was aware of the Hitec / Multiplex buy out.

Based on the feedback so far, I am leaning towards the metal geared

Ian

Robrow

Hi Ian, it seems to be the commonly held perception that for Multiplex read Hitec but in reality this is not the case. Although there is some commonality of parts between the 2 names the Titan 4 servos I am using have a different motor and amplifier to the Hitec equivalent. This is also not to say there is any difference in quality between the 2 brand names.

In my experience you will be very happy with the performance of the carbonite geared Mpx servos. I have at least 18 hours flying over last season on 4 of them in my Merlin 160 powered DV8R, they are on the primary control surfaces and the gear backlash is exactly the same now as new i.e. none!!

I have also been very happy with the latest Hitec servos, might be worth your while also taking a look at the TG's

Horses for courses at the end of the day, hope that helps, Rob.

Roger M

Ian,

From my experience of Karbonite in some HS56 servos, they are delicate gears and wont withstand any serious shock such as catching a control surface on something solid and I would only use metal in the future. Having said that I did use a Karbonite geared servo to drive the elevators in my L39 and that was OK.

Roger

JohnMac

Harry,
That is essentially true BUT, whilst Hitec are building some servos for Multiplex now there is a couple of points you should know. Firstly the amplifier design is all Multiplex. Secondly they are not just badge engineered. Multiplex have insisted on a better component spec for anything thatsays Multiplex on it. For example, the Titan sevos have an apparent Hitec equilalent but the motor and amp spec is different.
BTW I have used carbonite Titans in my Eurosport for a couple of seasons now with now issues.
Regards,

John

HarryC

My Feedback: (1)

Thanks John and Rob, thats reassuring to know.

Incidentally a friend of mine bought some Hitec karbonite servos and for curiousity took one apart to look at the gears. Only half the gears were karbonite, the others were normal nylon, he was rather annoyed as he felt the advert was misleading.

H

PS - John, how is the Viggen?

GJr.

My Feedback: (3)

There were several posts in the Radio Manufacturers Support Forum about Karbonite gears. Some of the comments were about the fact they do not handle shock loads well as they tend to be much more brittle than nylon or Delrin. They also have a big warning about not using any kind of "loctite" products for anti vibration help. They claim it causes the "Karbonite" to become very brittle, crack, and fail.