SmokinJoe

Has anyone tried the Hitec 5476HB Karbonite geared digital servos in QM40 racers? I'm about to order some digital servos for a Sumptin Else and would appreciate any comments on these servos.

What other Hitec servos would you recommend?

daven

My Feedback: (1)

I have not tried that specific Hitec servo, but I have used Hitec MG 5245 Digital servos in them, and they work quite good. Lately, I have switched to the Futaba 9650 digital for nylon gears, and slightly less weight. Both work well though.

SSAN

I have not use that servo for any race plane due to size, but I have 2 on a trainer. They are very precise and fast. I really like them for their precision centering. Also, I love the karbonite geared for their durability and no slop what so ever. I think its the best sport servos for the money for what it is.

As for servo for Q-40, go with what Dave recommended. Those are good servos, except the Hitech is a little heavier than the Futaba.

SmokinJoe

Dave,

Did you find that the 5245 metal gears wore quickly and developed slop over time? If they did, how long did it take before it became a problem?

Do you know if nylon gears are available to fit into the Hitec 5245 servos of the metal gears do wear prematurely?

daven

My Feedback: (1)

I would agree, that the knock on metal geared servos is premature slop and weight. I've used the 5245's for some time and haven't had any issues yet. I am not aware of a nylon gear set that would fit the 5245's. The Futaba 9650 mentioned above is priced about the same as the Hitec's, are lighter and have nylon gears so it has been a no brainer to switch for me. JR makes a 3421sa servo that is also VERY good, probably the best for this application, however it is also the most expensive. If you get the "sa" version, it will have nylon gears.

I only use these mini might servos on elevator and aileron. You don't need to use them on rudder or throttle. For those two surfaces you can get away with less expensive Hitec 225's, Expert SL 451's, I've been using Futaba 3102's for them, but you can get a way with the cheaper servos I mentioned.

airbornrc

My Feedback: (9)

Karbonite is very stiff and wear resistant, but fragile. I have seen several fail due to a shock that would not have effected a nylon gear.

Mark

rcbill

My Feedback: (1)

I would not touch Karbonite gears. I had several strip out on me with no crash and used a very short period of time. I also know a guy at a hobby shop that repeairs cars etc. and he put me wise to the problem. He warned me to check all my servos just to be safe because he noticed what I was flying at the field. Boy was I glad he mentioned it to me. Even with a short run time on them they were very noisey around center. I took them apart and some of the teeth were in fact stripped out for no apparent reason. I wrote and called Hitec and they basically told me that there was not problem and it was my tuff luck. I will never buy another Hitec. Also after comparing Futaba and Hitec side by side I noticed that with servos of about the same torque and the same speed the Futaba will reach it's end faster and center faster than the Hitec. Thanks for listening and good luck.

luv to race

My Feedback: (1)

Wow.. I thought Hitec was a great company? I heard just the other day about a guy who crashed a plane due to RX failure. Apparently, Hitec repaired all the radio gear and wrote him a check for the plane. Maybe it's all in the approach?

smoke

SSAN

Hey Randy,

We'll see how good they are since my buddy, Tom, crashed his SAM-RAI on the first practice flight on Saturday morning before the race start at Speedworld. His Hitec 225 aileron servo locked up after coming around Pylon 1, and made the plane spins and rolls without control, and came over the starting line and over other pilot heads. Tom did what he can, including inverted loops in trying to save the plane and keeping it away from crashing into the pilots station. Fortunately, he managed to get it out to a safe area and crashed the plane about 50 feet outside of Pylon 2. It was a scary feeling as I told my partner to shut down and yelled out LOUD to look out. It was a good thing no one got hurt, but bad thing that he lost his only plane before the start of the race. Never the less, he was really pissed off about it. Hopefully, Hitec will do something for him since all he uses is Hitec servos and receivers with his Futaba TX. I have a couple of 5245MG too that need to be send back to Hitec for repair or replacement.

This is NOT a bash to Hitec because I know it can happen to any other manufaturers as well. I'm only mentioning this because we both have been using all Hitec servos and receivers for years and have never contact them for any reasons before.

DHG

My Feedback: (7)

Sam,

Did that servo have the Karbonite gears, and was that the problem?

I have servos on my Christmas list ... takin' notes ... [:-]

Duane

daven

My Feedback: (1)

225's don't have karbonite gears that I'm aware of. One of the stand by bargain servos for racing, I've run over a 100 of them without an inflight failure (crashing doesn't count). They have never been the best centering servo, but great for a beginner pylon guy on a budget.

I've used the 5245s that Sam mentioned. I like them, just a little heavier than I would like.

Hitec has always been good to me, hard to beat for the price you pay.

SSAN

Duane,

Nope. It's was the regular HS-225BB with nylon gears.

HighPlains

My Feedback: (1)

A good reason to use two aileron servos in racing aircraft, you know, as in 'an ounce of prevention'.

daven

My Feedback: (1)

An ounce of prevention couldn't have been said better (considering your average mini servo runs about an ounce). I've never tried it, but know there are several out there mixing in a little flaperons with elevators for the turns.

luv to race

My Feedback: (1)

I think servo failures are just part of the deal. We all have our favorite brand name, and they will ALL fail (in time). I had 2 of the 225 hitec servos fail. One was on V-tail, one servo went to full lock (up) thuslly the plane started looping hard. I shut it off and saved it, by holding full down until it just fell out of the sky into a field. Lucky more than anything else. I certainly didn't make a huge stink about it, nor did I request Hitec to replace any broken airplane parts. I just chalk it up as bad luck. I've also had a elevator servo JR 3121 fail in a Q40. The thing just quit, I have no idea why. Lucky again...it was on landing and I was only about 10 feet off the ground. Still going about 50 mph, the plane pancaked into a grass field. Bent the landing gear super bad. Fixed that, put in a new servo and I was on my way. Had a Hitec switch fail (I think) in a new Q40, that sucker flew away and I never found any of it.. tell me that doesn't suck.

Bottom line, failures will happen.. nobody can prevent it.

Randy

daven

My Feedback: (1)

I had a brand new futaba switch go bad on the 2nd flight of a Vortex. The plane did loops right over the field, completely locked up for over a minute until the fuel ran out. As soon as the engine died, control came back and I was able to safely land the plane. Had that plane crashed (it was my first Vortex) I probably would have never ordered another. On the ground you could shake the switch a little and get intermittant control. That was also the last plane I ever installed a standard switch, everything now gets a brand new HEAVY DUTY Gold JR switch now. A great switch in my opinion, but I'd love it if they shortened their leads.

I've used every brand of stuff, and had mostly minor problems with all of it. I just try and pick the best product form each company (batteries, switches, servos, receivers, etc..) and go with it. My quickie planes would be a sponsors nightmare: Futaba 9650's on elevator, Hitec 85 on throttle, either JR 3121 or Expert SL451 on aileron, Fly Fast Battery, JR switch, and either a Hitec 555 or Futaba 149dp for reciever.

splatt

At least the model had good trim, Imagine a typical model, chances are it wouldn't last a minute stuck in a loop. Not at 170 MPH's at least.


I'll bet that was fun to watch

daven

My Feedback: (1)

I was just glad it was looping, if it went straight, I would have never have seen it again. Were you there that day? I had time to wait while Jerry B. went and grabbed his transmitter and turn on (same freq) while I turned mine off to see if it was possibly my transmitter. I held the transmitter on the ground, tried everything. Just big lazy loops at 170mph, each one taking it a little further to the North.

Very Lucky.

splatt

Where was I?

All I'll say is my leash is not as long as yours..

garys

Dave,
I had a similar experiece 10 years ago, only it was with an airplane I had quite a bit of time on, and had just won the Nat's with a couple weeks earlier. I flew one flight and it was fine. On the second flight, the second time around #1 it locked up. It continued turning around #1 with the circles slowing becoming more like loops, with the bottom of them about 20 feet off the ground. I tried everything I could think of, and ended up holding the Tx at my side waiting for it to hit the pavement. As a last ditch effort, I tried the radio again as the engine died, and it worked. Landed fine. I changed out the switch, receiver, and battery, and flew it at the next race...and crashed it there instead...at least it was a freebie at that point. lol
GS

daven

My Feedback: (1)

Mine ended up in a midair in Rockford a couple months later with Gary Helton...

At least that wasn't the componoents fault.

plankdriver

Hi,
I am trying to get more current information on what servos to use on my just acquired Q40s. I have some Hitec 225 as well as a few Futaba S3002. I know the S3002 are up to the tasks but are a bit slow. Are the HS225 tough enough to take the vibration.
Any recomendations? prefer futaba but I am not restricted to any brand.

Thanks

Santiago "chago" Panzardi

sahartman21

Concerning servos for Q-40: The Futaba guys use the following with a 5 cell receiver battery pack:



Aileron - S3002

Elevator- S9650

Engine Kill and rudder - S3102

garys

Chago's coming back to racing?

3002's as you said are up to the task (probably one of the most reliable servos ever used in pylon) but a bit slow by today's standards. I'm using the following...
For Q40's
9650's for aileron and elevator
3102's or 3150's (on my newer stuff) for rudder
3102's on shutoff

For Q500
9650's for aileron and v-tail
3102's on throttle

I'll probably be switching to 3150's on throttle and shutoff's before too long, but I still have a bunch of 3102's.

Welcome back!
Gary Schmidt

SSAN

Wow! Its been a long time since I posted the response. After many years, and looking back now, with different stage of experimenting with different servos, I will stick with the big names such as Futuba and JR brands due to their precision centering and reliability. I do really believe in the value on you get what you pay for. With that said, the choices are as follow...

Futaba:
3115 for all for throttle application
9650 for both elevators and ailerons
3150 (for elevators) new option and will try that sometime later

JR:
3121/SD3421SA for elevators and ailerons

Hope this helps those looking for real world experiences and answers. But it's up to your decision.

Best Regard,
Sam