softail99

My Feedback: (33)

Been reading lot's O' stuff here about the dependability of HiTec servo's. As I recall it's been confined to the digital group.

What is the real lowdown on these servo's? I have installed a bunch of these for other pilots as well as myself and not heard of any problems with them until reading this forum.

Does anyone have some long ter real experence with these that is willing to give us some good info?

Thankx

Rick

ajcoholic

My Feedback: (10)

Here is my story...

I have been using Hitec servos for about 10 years. I have bought and flown (regularly) everything from numerous HS 80/81/55 in my small planes, to many 605's, and many 425's. I also have 4 planes (2 giant scale gassers and two turbine jets) that have flown with the 56XX and 59XX series digitals, as well as a bunch of the giant scale digitals.

I have had a few of the older HS80's fail, and have worn out some 425's but to be fair, I have used allmost every other brnad (and still do) of servo including many airtronics, JR and Multiplex and have had all brands fail at one or more times.

Untill I started reading about Hitec servos here, I was a happy and content modeler enjoying my Hitec servos. Then I got scared and figured ALL of my planes were about to "fall out of the sky"... Then I got a dose of reality and realised that I was flying planes for years on these servos and have had very good luck with them.

I dont bother reading the negatives anymore, or if I do, take them with a grain of salt and not think too much about it. I know countless others who use Hitec servos and they seem to be as good as anything else, as long as you select the proper servo for the application you need.

Just my opinion...

AJC

softail99

My Feedback: (33)

Well, wouldn't you know it! After reading some of this stuff I thoght I'd better start checking out all my HiTec servos on the shelf. I have a number of building projects in line and baught a stock of servos to go with them. For the first time I started useing Hitec's for my own use. Right out of the box last night out of 45 new digitals one was busted and would not function. Opened it up to find gear and case damage, alowing it to hard over. what am i to think of this? I have been building for myself and many many others for 25 years and to tell ya the truth i've had one of my own servos fail and that was a 531 JR just this past year. Result, total loss of Heli. Now I don't know what this means.

Rick

ajcoholic

My Feedback: (10)

It means that no companies product is 100% bulletproof.

From a batch of 4 or 5 JR super servos (4000's) I had at least 2 go bad on me (just stopped working).

From a set of 5 Airtronics contest heli BB servos I bought all together, I had 2 fail within the first few hours (would only work one direction off center).

I have had other brands of servos fail also, and a few things go wrong with 3 different transmitters (out of about 12 or 13 I have owned in the past 20 years).

No one company has 0% failure rate, and if you are in the hobby long enough (or happen to be unlucky enough to get a few bad ones) you will experience a failure, no matter who's product you use.

Again, just my opinion...

AJC

AJC

rcflier_gi

My Feedback: (2)

I've been using Hitec servos since 1989 and I have had one fail. That was a throttle servo mounted in the wing on a profile plane and would get a unhealthy coating of exhaust residue after every flight.

softail99

My Feedback: (33)

I spoke with a large distributer of HiTec Futaba and JR, among others and he tells me he has had only 3 Hitec's come back on him in the past several years. I don't remember just how many years he sad but it was 10 or more. 2 digitals and 1 analog. That's not all that bad of a record. He mentioned it was about the same for the others but he seels far less of them.

Rick

Tired Old Man

My Feedback: (1)

As a long time user of both JR and Hitec servos, I can honestly say that I've been very happy with them both. Many years prior, I had the pleasure of using Futaba and Airtronics. Overall, they have been very reliable and work well in any situation that they are designed to handle.

More servo failures are brought about by people installing one that was not designed to handle the type of flight load or speed that it is being subjected to. Others fail due to binding caused by installation error.

Have I had failures? Certainly, but I build and assemble a lot of aircraft. Not just for myself, but for others as well. It's reasonable to presume that there will be the occasional black sheep that gets through. Personally, I don't believe that any of the major manufactures market bad products.

Pat Roy

cap10b

Love the analog servos, stay away from the digitals is you fly anything expensive. Your not gaining anything but using a low end digital servo. Just my opinion but if you want to save money buy a cheap motor or a cheap plane but dont skimp on batteries or servos.

jds

There is no problem so great that it cannot be
solved by a suitable application of engineering, horsepower,
or light explosives.

spend2much

My Feedback: (1)

I have a question for any of you..... i too have been using hitec servos a long time now with very good luck. Here is the question:
Have any of you, or any of your friends had any of the new versions fail? HSxxxx-HB
I just built another Helicopter, installed one HS-645MG for the collective, and during set up the servo would just take off to where ever it wanted to go.... I tested the servo on my Hitec servo tester, and it does the same thing on that as soon as it is plugged in. Now this one just happend today, and it is not the HB version, but it is of the new models, because it came with the new servo horns that the HB styles with the Karbonite gears have.
A week ago I had another failure...... Becaus I use that hitec servo tester/ programmer I bought one of those digital standard HS-5475HB servos for use on the throttle of my GP Patty Wagstaff, running a Moki 2.10. after about 3 flights no troubles at all. 3 days later another flight and no response from the throttle.... then I noticed that the servo would just run non stop, and would only stop at one stick setting. dont know how, but it sheared off about 4 teeth from the center gear that runs the final drive gear. I am using JR radio in my planes and Helis, and like I said, have never had any troubles.... Matter of fact, all the other servos in the heli and Plane that I was speaking of are all Hitec, but not the new HS---HB versions.

Anything I should look for? Has Hitec been bought out or something?
Thanks for any input.

Tony

Tired Old Man

My Feedback: (1)

I had one of the analog 645s' fail on an elevator half about a year ago. I think that one was just worn out from a lot of use. Got the plane back intact, though.

I've recently had some experiences (plural) that were somewhat less than ideal with new digitals. I'm starting to think it's like rolling dice.

mr_matt

My Feedback: (10)

huh?!?

You posted this, right?

http://www.rcuniverse.com/forum/m_18...tm.htm#1843016

Tired Old Man

My Feedback: (1)

Yea, I did. I was rather hoping a certain manufacturer would carefully assess some servos and call the spade a spade before they returned them, and perhaps accept a share of the responsibility. I should have known better.[:@]

I got the servos back this afternoon with the explanation from the manufacturer. Right now, I'm VERY sorry that I didn't more accurately reflect my true sentiments.

OF COURSE the problem wasn't that of the servos or the manufacturer. I should gave my head examined for thinking for a NY second that they would EVER accept responsibility. For the non-believers, look around. What other servos are you reading about that are consistently giving up?

My hobby dealer is laughing his ass off in a real quiet way. He warned me about just this scenario a couple of years ago. He'll sell them, but you will get warned first. "E Caveat Emptor"

Mr_Matt, I have to COMPLETELY agree with you. I'm now JR all the way.
At least they have come out and admitted when they screwed up. Even had product recalls to correct the problem. That was a few years ago for those new to this hobby.

mu2driver

My Feedback: (15)

I had the 5475 gears fail twice, be cautious with them.

Mac_Man_UK

As a guy that repairs servos ( JR ), MOST of the failures can be directly attributed to bad installations ! Looking at the body top, there are usually indentations where the mounting screws have been overtightened and/or the user hasnt cut away the servo hole sufficiently.

This means that the antivibration mounts are as much use as a chocolate teapot ! Poor old motor then is being vibrated all the time and dies. Occasionally if wired up incorrectly, the pcb blows. And rarely still, we have a genuine servo fail, but this happens in all electronic items.


[8D]

HarryC

My Feedback: (1)

I understand what you are saying Mac-Man. However, of every handful (4 or 5) randomly chosen Hitec servos I have been given to install in other people's models, at least 1 and sometimes 2 of those servos have committed suicide on the bench before they even got into a model. Some have been faulty from the instant they were switched on, some went mad after a couple of minutes testing, one shredded its gearbox just being run on the bench - it wasn't in a model, it wasn't connected to anything, it had no load, and it shredded itself within a few wiggles of the stick. Some are just so jerky and have such an awful non-linear response that they are not useable. One died in the air on just its third flight, causing a crash and writing off a model. I recently got persuaded to try buying 4 Hitec digitals, 2 of the 4 were faulty straight out of the box. How can I have a nano-shred of faith in them? I am not therefore repeating third hand rumour, I am working with direct first hand experience of Hitec servos. I install them in other people's models if thats what they supply but hell will freeze over before one Hitec servo gets inside any of my models.

I don't get that junk level of unreliability with JR servos. I buy dozens of JR servos and the only failure I have ever had was with a very old very worn out JR servo.

H

XJet

And just to balance the ledger a little -- I've got 12 Hitec servos (from the little HS81 to the 1/4 scale HS700) and so far I've had no problems at all.

Likewise, I know a number of turbine fliers around here who use Hitec digitals, seemingly without any problems.

I'm not jumping to any conclusions in respect to this -- just adding another data-point.

Tired Old Man

My Feedback: (1)

If you look at a bigger picture, what is the aproximate ratio of people describing bad experiences with Hitec servos compared to writing about a bad experience with the other major brands? Looking at it that way, even allowing for a possible (probable?) higher market share held by Hitec, the results will come out disproportionately high.

I've been actively involved in R/C flight for about 35 years now, and I would hope that by this time I've learned how to set up a radio installation. I'm no electrical technician, nor physics wizard, but then again, I think most of the people in this hobby reside in a similar catagory.

I know without question that an hs525mg failed on my 30% Extra 230 on one elevator half last year, sticking in the full down position. I was VERY lucky to have saved that one.

I am reasonably certain that one brand new 5945 failed on one of the ailerons of my also brand new Wild Hare 28% Edge 540 on the third flight. Fisrt with an uncontrolled rapid cycling stop to stop, then sticking in a high rate position. A grand total of 13 minutes of flight time between all three flights. Aircraft destroyed.

I am VERY certain that another new 5945 being range tested for the first flight of my brand new Wild Hare 28% Extra 300S stuck in the full up elevator position while I was about 6 feet away from the plane. Went home and pulled out ALL the servos. All 5945s'

I also know that Hitec returned 6, 5945 servos to me stating that two of them (all new) had "damaged amplifiers" Not defective, not improperly installed, but damaged. They forgot to mention that one of the case tops had an elongated hole where the shaft pin holding the center gear cluster inserts into the top of the case. It looked an awful lot like an assembly error. It's the implication that I was the damaging party that has really set me off. It's also the thought that they either can't, or won't, accept responsibility for what appears to be a defective product.

I've gone through everything that can possibly be checked on my end, and I have another plane set up the same way. This time with JR, and no problems. I still have the wings and empennage from the Edge, and no one else can see an installation set up problem either.

Buy what you will, but if you cannot have ABSOLUTE faith in the product you are purchasing, you shouldn't be buying, or using it. Aircraft can do terrible damage if control is lost. You want it on your conscience?

XJet

The problem is that you can't have "absolute faith" in any servo (or receiver or battery pack for that matter).

All complex devices have a probability of failure -- it's a fact.

It should be remembered that a lot of people buy Hitec servos because they're often a point or two less expensive than the equivalent Futaba or JR unit. While the specs and performance of Hitec seem to be every bit a match for their peers from other manufacturers, perhaps that lower cost comes from less "over-design" than is found in other units.

Having designed a lot of electronic equipment in my day, I know that over-design (ie: designing in a higher safety margin in terms of component specifications) can add to the cost of a product -- but it can also result in a vastly more reliable device when it is occasionally operated outside of its intended operational envelope.

Maybe (and I'm just speculating here) Hitec are able to lower their manufacturing costs by designing "to spec" rather than building in a high margin of safety.

If servo amps are failing, it's possible that the switching devices used in the output stage are rated for less current/power than those used by Futaba/JR. That would make them cheaper and, providing they're not subjected to exceptional loads, they'd still work to spec.

Think of it like comparing a Toyota RAV4 to a Hummer. Both are spec'd as being "off road" vehicles with 4WD and capable of negotiating uneven terrain. And, providing you are careful and don't attempt too steep a grade or too uneven a surface, both will get you from A to B. However, the first time you come encounter a few huge boulders, odds are that your RAV4 will end up breaking a suspesion member or stuck high and dry -- while the Hummer just carries on moving.

This can also explain (to a degree) why there appear to be so many reports of Hitec servos failing out of the box or within the first few minutes of operation. If you're using electronic components that are operating at or near their maximum ratings, there's far more chance that any tiny manufacturing defects will cause premature failure of those devices.

A transistor or FET junction that is imperfectly formed may generate 20% more heat than it should. If the components are operating at just 50% of their rated capabilities then this increase in dissipation may not cause a failure. If that component is running at 90% of its rated capability then failure is almost certain.

Ultimately however, it's down to price versus value and this is a judgement call that everyone has to make for themselves.

There are happy (insert RC brand here) users and there are unhappy (insert same RC brand here) users -- just as there are happy (insert vehicle brand here) drivers and there are unhappy (insert same vehicle brand here) drivers.

Tired Old Man

My Feedback: (1)

Well written.

mr_matt

My Feedback: (10)

Good analogy, if I could get a Hummer (the best) for 10% more money than the RAV4 I do not think I would have a very hard decision to make.