jtholley03

My Feedback: (4)

I am reading about Karbonite output shafts snapping. I have three 5975's on the tail of Sig Cap. What is the official stance on this problem?

Thx

MikeMayberry

My Feedback: (1)

We are evaluting the situation. The hand full of failures we have seen have come from high vibration applications. We're flying the 5975's in a 1/4 scale cap and have had no problems.

P-51B

My Feedback: (5)

What, exactly, are you defining as a "high vibration application"?

MikeMayberry

My Feedback: (1)

Throttle and one in a heli.

P-51B

My Feedback: (5)

I'll have to watch this issue carefully, since I just bought two of these.

mglavin

My Feedback: (31)

I have four of the 5975's on throttle in 40% models. Probably well over 50 flights on a few of them. So far so good. I really like them. Smooth and fast!

KAD

Hey Guys, I just got a response from Hitec Service saying that the output shaft failures were due to useing Locktite on the screws that hold the servo arm to the shaft. The implication was that the chemicals in Locktite weakened the Carbonite shaft.

Geistware

My Feedback: (16)

Why would someone want to put loctite on composite threads?

Phily

Well what servo are you suggesting for a 90 size heli, to change to ?

Im Glad you are publicly stating this, I remember when JR were saying the 8411 had no trouble even with high complants.

Thanks.

MikeMayberry

My Feedback: (1)

The 5945's and 5925's are the best servos we have. After some testing we have found that replacing the stock screw with on 2mm longer eliminated the output shaft problem. We are waiting on new screws and will send out replacments when the become available. The stock screw length is 8mm so if you do replace the screw yourselves it should be no more than 10mm long. We will make an official anouncement about this shortly when they confirm the exact screw size.

Mike.

mglavin

My Feedback: (31)

One should NEVER use Loctite or anything similar with plastic components of any composition. As mentioned above Loctite or similar will react with the plastic, I believe it causes the plastic to become brittle.

Use something like Shoe Goo, PFM or Zap a Dap Goo. I use this on all servos screws metal or plastic geartrains. This provides a resilient or elastic type retaining component which is easily broken loose, unlike when you get carried away with Loctite type products.

P-51B

My Feedback: (5)

Good to hear there is a cause, and I shouldn't have to worry since I don't put locktite on 'em!

akflyer

My Feedback: (7)

It even happens with out loctite. I saw one snap yesterday on an aileron. No locktite was used.

I was going to put these on my heli but now am not sure if I want any more.

mglavin

My Feedback: (31)

Mike Mayberry suggested the following previously. This makes sense as the 2mm longer screw extends into the shaft below or past the gear spline.

After some testing we have found that replacing the stock screw with on 2mm longer eliminated the output shaft problem. We are waiting on new screws and will send out replacments when the become available. The stock screw length is 8mm so if you do replace the screw yourselves it should be no more than 10mm long. We will make an official anouncement about this shortly when they confirm the exact screw size.

akflyer

My Feedback: (7)

Are we talking about putting longer screws in the 5945's and 5925's or the Karbonites ???????
I will fix another drink while you reply

mglavin

My Feedback: (31)

I believe Mike was or is addressing two query's. I checked with Mike Mayberry directly and he confirmed the longer screws are intended for the Karbonite geared servos. [&:]

Mix one for me, I've been rewiring switches to accomadate my failsafe reulators and charge jacks...

FastLaneAK

[sm=drowning.gif]I am currently assembling a Raptor 50 V2. I have a 5975HB for the tail and 5475HB's for everything else. I am quite concerned(actually on the verge of loading my pants) that these servos will re-kit my new ,very fond of, Heli. Are these the right servos for the job? I wanted them for no slop but I don't want to buy new Heli parts due to servo arms departing the case with the splines still inside. Any thoughts??????[sm=drowning.gif]


Lane []

P-51B

My Feedback: (5)

Now I'm concerned again.

akflyer

My Feedback: (7)

Why couldn't a top gear for a 5945 be used in place of the top karbonite gear in order to make it tougher?? I would think that this would still keep the gear train tight with no slop and give them a little more strength. Any thoughts on this???

Leni [sm=confused.gif]

mglavin

My Feedback: (31)

I don't have any experience with these failures, but the longer screw make sense to me as it will extend deeper into the shaft past the gear spline, this should alleviate the stress placed in shear on the shaft at this juncture and share it with the metal retaining screw. It's highly unlikely you'll experience this problem in this location with the longer screw.

jtholley03

My Feedback: (4)

So do we have replcement screws yet? I have three of these I am using currently. Also has it bee resolved in the new ones?

mglavin

My Feedback: (31)

Check with Hitec for free replacment screws. I understand current production servos have been fitted with the longer 10mm screws.

Geistware

My Feedback: (16)

Yes the screws are in and you can also get them from tower hobbies.
they are 2.6mm x 10mm