Tee Bee

So…With all the new technology and product releases in the last few years, I’d like to ask the group what their servos of choice are these days for 1/2A glow powered models. Here’s some of my experience:

In the past, I used lots of HS-55s. They were attractive for their price, size, weight, torque, etc. Unfortunately I’ve had several failures of them as others here have also reported. Luckily I never lost a model because of them. They just got the jitters and I would replace them before ultimate failure occurred. I still have them in several older models but I don’t plan to use them in new projects. They were a nice fit for snug airframes like the Skydrill.

I’ve had good luck with HS-65s so far. They cost more, are larger than 55s, and are heavier. On the other hand, they seem to hold up to the environment that I’ve put them in. They are too large and heavy for some 1/2A or smaller applications, however. Some models just can’t handle the extra weight or don’t have the room for them. I will probably install them in my Scalpel project featured in the build thread here.

I bought a few Futaba S3111s a while back. They are a neat little, lightweight servo. Unfortunately, they are only rated at half the torque of a HS-55 and I am leary of using them on a 1/2A flight control. I do have one in my Scoundrel as a throttle control and it has worked flawlessly in that application so far. In addition, Futaba doesn’t recommend them for use with 6V packs(designed for 4.8V packs) and I like to use those in some of my models with 2.4GHz receivers to help prevent brownouts. I am thinking of installing them in my next TD .010 powered plane and they will probably work well in that service.

This was prompted by the fact that I’ll soon have to open up my wallet to buy new servos for my winter build projects. It seems that with the new technology, the receivers and batteries have gotten much smaller and more reliable. Servos on the other hand, though small and light, can have sketchy performance and reliability(Much like other stuff we import from China). Does the “dream servo” for our use really exist out there?

Troy

Max_Power

I'm with you on the 55's...just don't trust them. I know grams make ounces and ounces make pounds, But I'm the kind of guy that is usually willing to take a bit of weight penalty for confidence. For me you just can't beat $12, 16gram .09sec 36Oz torque HS-81's. Fairly narrow too and sturdy arms. I'm sure they are too heavy for a lot of 1/2a flyers, But I figure even if I have 4 of them total weight difference is only 1 ounce more than 4 HS55. Todd

Tee Bee

Double post. Dumb thumbed my Iphone again.

Tee Bee

I agree, Todd. I have also used HS81s and really like them. Just bought 3 more in fact for an upcoming build. I didn't mention them in the previous post because they are just too large for many of my models.

Jaspur_x

My Feedback: (1)

I just got a cox icon system from Bernie and went with the cox cs6 micro servos for that in my micro stick, and if I get good results will go with same in the Lastick I`m doing for my next build.

Good you brought this up, I was soon to do it myself as I`m way behind on the tech info. I`m still using my 80`s futaba and a hitec focus 3 for most of my flight duties lol

So fill us in guys, are we doing well?, are there better buys?

rcguy59

My Feedback: (8)

I too am a fan of hs-81 and hs-82mg servos, but I consider them a bit much for all but my Herr Engineering birds. Awhile back one of my flying buddies gave me a pair of Hobbyking 939mg servos. They are the same size as the hs-55's but have metal gears and a bit more torque. They are also sold under the "Corona" name. I have about 20 of these in 1/2A's at the moment and have yet to have a failure of any kind in over a year of using them. Best part is they are about 5 bucks apiece. I have had a few crashes and multiple hard landings and have yet to strip a single gear. I'm sold on these little guys. All of these planes are powered by Norvel 074's. Most of these planes also have the Orange Fast RX's from HK, too. No problems there, either. Lets me save the expensive FASST RX's for the bigger stuff. I would hesitate to use these servos and RX's on anything much larger, but for what I use them for, they've been brilliant. There is also a digital version of this servo available now for about 6 bucks or so, but I haven't tried any yet. Hope this helps.

Tee Bee

Thanks, rcguy59. That's just the sort of info I was hoping this thread would bring out.

rcguy59

My Feedback: (8)

Glad I could help. Something I forgot, though. Bernie up at Cox International has these great little RX batteries I've been using. IIRC, they are 220mah NiMh 4.8V packs. Quite inexpensive and no problems at all with them. I wish he had 5-cell packs, but I'm not complaining. They come with JST plugs which are usable after a bit of XACTO action to the little ridges on them. You just have to pay close attention to the polarity.

forsakenrider

Hey RCguy, got a link to the servos youre talking about? those do sound great.

I mostly use HS55's but Im a little weary....

Andrew

[link=http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=14459]Corona 939mg[/link]

I have also been a proponent of slightly heavier servos - not so much for the advertised torque, but because microservos have such tiny geartrains that are very susceptible to stripping. With the advent of very small metal geared servos, this has solved the weak geartrain problem.

I guess I'm too old school, but I can't see spending hours and dollars in building a plane, then trying to save a total of $5.00 using inexpensive servos that may be a little sketchy.

Tee Bee

Okie dokey. I just ordered 4 of those 939MGs for the price of 1 HS65. If I like them, I will install a couple of them in the Scalpel.

That was my first purchase from Hobby King. You guys are helping to stimulate the economy and redistribute the wealth.

Andrew

Yeah - in China!!!

airraptor

My Feedback: (66)

The Hitec HS45 digitals are a great servo and can use the HS-35 on throttle if set up correctly.

as for the 81-85 size servos DO NOT USE the plasitc geared ones. they strip the gears way to easily. I have had many strip just with the application of power. use the metal geared ones if reguire the power of the 81-85 servos.

Now the HS65 HB sevos are very strong and i use them on everything from 1/2A's the throttle servos on moki 2.10's they are a great servo at around 20 bucks.

for light battey's i use the 200 Mah hobbico liFe from tower also very light weight and can be even lighter if solder on 22-20 gauge wire. comes with 16 i think.

anyway you can easily get 5 servos (two wing) batter, reciever, control push rods and switch under 2 ounce's.


EDIT : 1 ounce to 2 ounces fat fingered keyboard

Mr Cox

I don't follow the math here. 5 servos alone would be about 1oz in my world?

DustBen

My Feedback: (3)

I've been using these:

http://www.hobbyking.com/hobbyking/s...sec_18_8g.html

I bought 2 to try and now buy 'em 6 at a time.
I'm using them on my 72mHz Airtronics system and have no complaints.

buzzard bait

I've got my eye on some Dymond servos. The 200s have long been well-regarded as rugged and accurate, but they have a very wide range of sizes now. You won't get them for $5, but the prices are very reasonable. I've also tried some HKT900s on my Little Extra w/ASP .12, which were under $5 each, and liked them so far.

Jim

049flyer

My Feedback: (18)

I've been using Hs-81 servos for years and have never stripped a single gear. They seem plenty strong for me.

Truckracer

My Feedback: (19)

Agree completley .... have used dozens of these things and only stripped a gear in a major crash.

Tee Bee

My Pong Two planes have flown literally hundreds of flights(and a few bumps) over the last four years and the HS-81s have held up just fine. They're just too large for most of my .049 planes. Squeezing 9g servos in some of them is an exercise in high school geometry.

eroc144

My Feedback: (1)

+1

I've learned that lesson a number of different times & ways, and now gladly shell out $20/servo for reliability and piece of mind.
[ul][*] My experience with Hitec 55s has been quite good, but man they seem fragile. I have them in my DNUs.
[*] Hextronik HXT900's used in my Counterfeit Extra locked up on the 3rd flight. R.I.P. Now I only use them in my flat Foamies.
[*] Hitec 65s have a higher current drain under load than most other "1/2a" servos, so watch your battery size if you're using several of them with a 4.8v system. The receivers in my Pacer .15 and Chea-Pass Stik browned out - guess which one crashed and which one recovered? I use a 6v battery or a Spektrum capacitor to "level out" any load surges that could reset the receiver. I've also had a higher failure rate with these servos than with any other model / brand. Hitec replaces them for free but eventually one will die in the air...
[*] I use HS-81s for my "larger" 1/2a stuff. My overall experience with them has been good and I've only had one die outright - luckily on the ground during pre-flight! That said, they're noisy and chatter incessantly around center. I did have a pair strip this summer (the plane actually righted itself and landed softly in the weeds. My best landing this year I was told...). It was on a Counterfeit Extra and I'm reasonably sure it was due to aileron flutter, so let's blame the builder.
[/ul]
I picked up a few Spektrum A5040's this summer and have been quite happy so far. Of course these aren't really 1/2a servos and I use them on my .15's and .30FS planes. (GASP! Did I say .30!?)

Has anyone tried the GWS Naro Super series digital servos? The specs look really good.

EG

Mr Cox

I haven't tried those but I have tried other digital servos, and the power draw seemed higher. I only got about half the flight time when I use two digital aileron servos (from Power HD).

Considering how important the servos are I don't like to save money on them. Tried HX servo from HK once and will never go there again.
HS 65HB, and HS 45HB are fine. HS 81 for larger planes (around .15). Dymond was meantion earlier and the Dymond 47 is very good, comes with dual mounts (regular of flat).

Andrew

I also have a lot of HS-81's, but they are a step up from the HS-55 and other sub-micro sized servos. It's the sub-micro servos that have fairly fragile geartrains. The size requirements that Tee Bee has for his plane precludes his use of the micro servos. So, it really wasn't a question about the durability of the HS-81, but about the durability of those half the size of the HS-81.

Tee Bee

True, Andrew. I was referring to the smaller sizes needed in many of our planes but this is all good discussion as the 81s are an option in some of the designs we fly.

I've found the size of the 55s to be ideal in lots of the planes I like but wish they were as robust as the larger ones available.

Still wishing for that "dream" servo.

airraptor

My Feedback: (66)

I am glad you guys have had great luck with the 81's. I flew with four of them in a 180 mph plane with a Jett 35 and were just fine. so i bought more for other planes. i put 4 more in a fliton AJ 3d plane that is only 45 ounces and flys less than 50 mph. well soon as i installed them and turned power on with 6 volts two stripped just with power on. replace gear train. then second flight the elevator stripped out on landing. i will never use the 81 or 82's again. i do like the 85MG and the 85MG digitals thought very good servo's and the new HS-87digital HV is great also.

Hitec also has the HS-56HB which should be a great servo also. I love the HS65HB out of 40+ servos only had two problems. one didnt work at all from the begining and the other striped gears when I crashed a plane. i have also had the strength of the gear train tested. once on my revolver with a saito 91 in it and the HS65HB mounted on the firewall. the engine mount broke off and the engine was only hanging on my the servo. I have inflight video showing it. another time in a crash the servo arm was ripped off just leaving the screw and plastic under it. the gear train was still intact and worked perfectly.

buzzard bait

It looks like finding the "dream servo" will require more testing of what is out there. Very few types have been mentioned so far in this thread. The very few references I've found to Dymond servos suggest they have rugged gear trains. They are available in more or less 1 - 2 gram size increments up to about a 1/2 oz (the highly regarded 200); larger sizes beyond that, http://www.rc-dymond.com/index3.php?categoryID=17

Metal gears are available in many of these sizes, including very small ones, some are digital, prices range from $7 to $20.

I will be needing some small aileron servos soon and will give the Dymonds a try.

Jim