vol4ever

Browsing Tower, there seem to be 100's of Futaba servo models. I've always just used the plain jane S3003 (currently $9.89) except for cases where hi-torque was called for. S3010 ($22.49) there. FYI, I typically build regular 0.40 and 0.60 size sport planes, and I've *never* had a problem.

It's about time to start my winter project which is looking to possibly be a Great Planes Ultra Sport 40 Plus or Ultra Sport 60. My radio system is showing some age, so I was thinking about upgrading radios while I was at it. The 2 I'm looking at are Futaba 7C FASST and Futaba 6EX FASST. Is there a compelling reason to also buy the new digital servos? Radios aren't that bad, but servos can quickly escalate the cash layout.

Just curious on opinions.

Gringo Flyer

My Feedback: (18)

The new Futabab digis are OK but nothing spectacular. I have a set and what I hate most about them is that you cant run them on 6volt. I bought them when there was a good deal with them bundled on a radio and a PCM rx. So to me it would really depend on the price difference. I you are talking $20 or so I would go digital. For general sport flying I dont think you will see much difference.

carrellh

Everything I've ever read about the Ultra Sport says plain ordinary servos are all it needs. I've read that digital servos are power hogs. If so, you might need to buy a high capacity battery pack to drive them. I'd keep it simple and use the 'old school' parts.

bruce88123

It's a shame digitals won't work on 6 volts ya know. Here's a list of the ones Futaba currently sells in the U.S. that WILL run on 6 volts.
BLS351, BLS451, S5050, S9153, S9155, S9351, S9550, S3151, S9152, S9156, S9350, S9451 AND S9650. Hope I didn't miss many. Surely Gringo, you can find one in this list that you will like.

XJet

I run all my "standard" servos on 6V these days and they work really well.

Most of mine are Hitec HS425BB or (more recently) the $5 Vigor VS2 units -- they're much stronger and faster on this higher voltage and I haven't had a failure yet (crosses fingers for luck).

I used to fly S3003 servos but there's just no comparison between them and the Hitec units when it comes to gear-slop and stability of the output shaft -- the Hitecs are MUCH better for only a little extra money.

Dr1Driver

Gringo flyer makes a good point. I'd rather have analog servos on 6v than digitals on 4.8. IMO, you don't really need digitals unless you fly Pattern or maybe Pylon. Nothing else is that precise for general sport flying. A steady hand on the stick is better.

Dr.1

vol4ever

That was my gut feeling. I was just curious if others recommended making the upgrade anyway for other reasons. If not digital, I'll probably at least upgrade to the ball bearing S3004, or look at some of the Hitecs mentioned by XJet.

Do all servos tend to hum when at rest? When the plane is on the workbench, the servos make a humming sound like when you try to manually move a control surface against the servo's hold. If you bump the sticks enough, all servos eventually will go quiet. I'm assuming the hum is no big deal in terms of harming the electronics. Does this same issue exist with the more expensive servos? Is there a radio setting that will get rid of it?

Dr1Driver

or look at some of the Hitecs mentioned by XJet.
Personally, I LOVE Hitec and Hobbico servos. Lotta bang for the buck!

Do all servos tend to hum when at rest?
When a servo hums or buzzes, it's trying to follow the stick position, but, for some reason, can't. Even a little residual friction in the system can make a servo buzz. A servo trying to center itself will buzz, too. I suspect the analog servos are worse than digital. The centering isn't as precise. If the control surface is very large, the sheer weight will make the servo buzz. When you move the stick, the buzz goes away, right? Then it's ok. Personally, I prefer no buzz, but it doesn't always happen that way.

Dr.1

vol4ever

Yep. I prefer no buzz myself, but it always happens with EVERY airplane I've ever built. More of an annoyance than anything else.

dirtybird

My Feedback: (5)

If a servo buzzes its wasting battery current. But its one of the evils we have to put up with if you want a precise servo. Be sure your controls are free and your surfaces are balanced. Then get ball bearing analog servos and you will have less trouble. You might want to run them in a bit when they are new - that will help. Put them on a servocycler for an hour or so

vol4ever

Sorry if this is a dumb question, but where do I get a servocycler? Never heard of such an animal, and nothing showed up when I tried a search on Tower. Is it just some sort of device that just moves the servos back & forth from endpoint to endpoint?

dirtybird

My Feedback: (5)

If you have a Futaba 9C the function is built in.
Do a google search for servo cycler rc. I turned up a lot of leads there

bruce88123

A few options. Not all of these will "exercise" the servo.
http://www.radicalrc.com/shop/?shop=1&cat=156&
http://www.york-electronics.com/

bruce88123

Also
http://www3.towerhobbies.com/cgi-bin...tER+&search=Go

vol4ever

WOW. Those are high $$. Thanks for the links, but I'll probably just live with the buzzing. I'm just a general sport flyer, so some of this extreme precision gear is a bit of overkill. By the way, I notice you are from Memphis. I work in Memphis, but live in Collierville. PM me & maybe we can hook up some time. Right now, I usually just fly by myself out in Johnson Park.

dirtybird

My Feedback: (5)

19.95 is high dollar to you?

vol4ever

No, but the $20 version looked like just a tester. I figured it would take the $150 beast to do the automated cycling.

dirtybird

My Feedback: (5)

I don't have one of those but the picture shows a button labeled cycle. I think that is what you need

vol4ever

I never even noticed that switch. At any rate, since I'm just a sport flying enthusiast, I'm not sure it's worth $20 to me personally. I'm sure it's an outstanding piece of equipment. I just don't need it.

dirtybird

My Feedback: (5)

If you plan to be in this hobby for awhile you will find that you need it more than you might think you do. Like any piece of test equipment it makes things easier.

bruce88123

30 years, haven't needed one yet. There have been a couple of times when it MIGHT have been nice to have but got by without one. Maybe I just need a few more years? I'll let you know.

vol4ever

Agreed here. I've been flying since the late 80's myself, albeit off & on. Until yesterday, I didn't even know these things existed! I still think they are more for the folks that are into extreme precision, pattern competitions & things like that. I could definitely see a NEED there. For me, it would just be another item gethering dust on the already crowded workbench.

dirtybird

My Feedback: (5)

I would not use a servo that I have not cycled on the cycler for at least an hour. I use my 9C and cycle them all at once. It checks out my servos and batterys and connections all at once. Any problems with anything in the system will usually show up. Then I can fly and less likely have a problem in the air.

vol4ever

I could see the value in checking the system as a whole. I'm close to buying my next kit plane & planning to upgrade radios with it. The cycling feature is one more to add to the list of things helping me figure out which radio to get. Futaba 6EX FASST & 7C FASST are the ones currently at the top of my list.

bruce88123

Hold out for the 7C, many more programming features for just a few more dollars. Same physical size RX. Check out the manuals online. Note: you'll have to read non-2.4 7C manual since the 2.4 hasn't been released just yet. Programming should be the same from what I've heard or extremely close.