wiskey007

I have a 28% WH Extra with 5945's all the way around. During final setup I noticed some "play" in my control surfaces. Thinking it may be my horns (Airwild) or my linkage setup (titanium rods + RC ball links) I began the process of elimination. Well after much time troubleshooting my equipment I could find no play in any. Ball links are solid, arms are locked tight on gears, no movement whatsoever. I then took out the servos to test. It seems to me that there is a good amount of slop in the top gear of these 5945's. Not between the arm and the gear but within the gearbox itself. I did not open a servo to see if there is a problem because I have the same thing in all 4. It translates to about 1/8" of play (deflection) at the control surfaces.

Have others experienced this slop with the Hitecs? Is this normal? What are all your suggestions/comments to help me see if I may be missing something? This movement occurs in the servo even with no arm attached. It's small but from what I read, everything counts! BTW-No flight time on these yet.

jelaird

My Feedback: (1)

I've had a lot of 5945's and they do have a small amount of gear train "play". But it has never been a problem with 1.25" or smaller servo arms. If you are using longer arms (for 3D throws?), the play is amplified and will be much more pronounced but it's the same for any servo then.

wiskey007

I am using 1-1/2" arms (the link is at 1-1/4" from servo axis point) for 3D throw. It seems like the movement may cause flutter and wear the servo gears possibly causing failure. Not sure it's a problem here. Any suggestions?

jdecker

My Feedback: (2)

I noticed the same gear play. But since it was on all 4 in this particular plane I just assumed it was normal. It didn't affect the way the plane flew and there wasn't any flutter. I probably have 50 flights on them. I have 4 more showing up today for another plane and I'll see if it is the same. I imagine it will be.

Is a little gear slop normal on the 5945's? I don't have experience with any other metal geared digitals.

John

wiskey007

Thanks for the answer. How about from those Hitec experts out there? Anything on this one???

ptgarcia

My Feedback: (36)

Is the gear play there with the radio turned on or just when there is no power going to the servos? Check with the radio system on and see if it makes a difference.

wiskey007

Yes, the radio, receiver are both on. The slop occurs at all ranges of deflection except at the maximum endpoints.

XJet

It sounds like the slop that builds up over time with any metal-geared servo used in an environment subject to moderate levels of vibration.

Nylon (and I assume Karbonite) are likely far more elastic than the metal used in servo geartrains so the metal will wear whereas the plastic gears will simply flex slightly and return to their correct shape when subjected to vibratory stresses.

If I understand correctly, Karbonite is designed to be a compromise between the strength of metal gears and the low-wear of nylon ones.

I wonder if Hitec will offer a Karbonite gearset for the 5925/45 series of servos -- I suspect there'd be a few people who'd love such a thing and it would be a good seller.

wiskey007

I guess it's similar to slop that occurs when the gears are exposed to excess wear. +

There's one important factor here though, the servos are Brand New "out of the box". Only bench tested. My fear is they'll just get worse over time.

mglavin

My Feedback: (31)

If you have excessive gear train slop send the servos back to Hitec with a note of your concern... This is not normal. I have used hundred of these servos, two of them had excessive slop out of the box.

FWIW: Hitecs gear train is well known for its lack of slop and ability to hold up over time, unlike those offered by others.

XJet

I just bought four new HS5925 servos and they have no slop -- however I do note that they all exhibit a quite variable amount of resistance when turning the output shaft by hand (without power connected of course) -- it's almost as if the gears are binding slightly at different points on the circumference of the final gear.

Is this normal? None of my other 24 Hitec servos (ranging from HS81 to HS700) have this characteristic, all exhibiting a constant resistance to turning with no hint of binding in the geartrain.

They appear to work fine in every other respect.

mglavin

My Feedback: (31)

XJ

This is common with metal geared servos. I believe the gears need some time to become acquainted with one another and develop a relationship so to speak... Once the gears have had a chance to work out there differences they exhibit smooth transitions.