serovs

[vtjeep]

Are the S9252 digital servos any good there is a servo pack heli pros has for $419 comes with a 401 and a s9254 and 3 9252 and a 3152 for throttle control.. is this a good setup ? ok one the same subject i was reading that the digital servos take a lot of power is there a better battery to make for longer flying time between charges or should i just buy two batteries ? I just ordered my titan kit and should be here Wednesday im very exited and just looking for my next step ..thanks

[vandelescrow]

I'll let someone else answer about the servos, I use JR. But about the battery, I'm building a R90 and I'm putting in the Scott Gray regulator so my cyclic and collective servos will get 6 volt. for the battery I have on order a new type of battery from Duralite, the LI-Mn, after speaking with their tech's they recomended the 3000mah battery. They said this battery will last several flights and can be recharged at up to 12 amp (only one amp on the yellow lead). they said 12 amp recharge will shorten the life of the battery but can be done. Their tech said these new chemistry batteries are actualy equivelant to a higher mah battery of other chemistries so we will see.

Check and see if those servos you mentioned will work at 6 volt, if so you will probably get higher speed out of them.

[ghtracey]

You'll have to let us know how those batteries work out. I'm a little skeptical about the last statement though. A mAh is a mAh, it won't change with chemistry, its one milliamp per hour, a measurement of capacity. Its like saying that your new plastic gas can with 5 gallons of fuel in it will run your engine as long as your old 6 gallon metal gas can... it just doesn't make sense, a gallon of gas doesn't change.

As for the other question, I use an Align 2-in-1 Regualtor on my Titan and love it. Low cost, great performance, and it ignites the glow for you too. Get a 4000ish mah LiPo and you're good to go.

[BarracudaHockey]

Thats about right. Rons has the 9252s for 71 and the 401 combo for 185, not sure about the throttle servo but if it costs more than 21 dollars separately then yes its a good deal.

[vtjeep]

ok but are the servos any good ...? should i get alot of use out of them .. im new so not sure whats good or not ? on that note is jr servos any better then fuba's ..

[AliasMrJones]

You'll have to let us know how those batteries work out. I'm a little skeptical about the last statement though. A mAh is a mAh, it won't change with chemistry, its one milliamp per hour, a measurement of capacity. Its like saying that your new plastic gas can with 5 gallons of fuel in it will run your engine as long as your old 6 gallon metal gas can... it just doesn't make sense, a gallon of gas doesn't change.


Not exactly. Different battery chemistries have different voltage sag under load and different voltage curves as they discharge. SLA batteries, for example, have a lot more voltage sag than Nimh or Li batteries. So a 10ah Nimh or Li battery under high load will last about 50% longer than an SLA battery of the same ah capacity. This voltage sag is due to the peukert effect. If you run the batteries at very low C dischage, they may have the same capacity, but under load the SLA battery voltage will drop off faster than Nimh or Li as you run the battery and you couple that with the higher voltage sag of the SLA under high load and you will get to the point that the SLA battery will hit the low voltage cut-out of your regulator/controller long before the Nimh or Li battery will because the Nimh/Li will be able to deliver a higher voltage longer under load. So, same capacity doesn't equal same run-time under high load. It is the combination of the battery's characteristics under high load and the fact that your motor/controller/regulator need a certain minimum voltage to operate that causes the difference rather than absolute battery capacity. If you want to run a small load, like say few LEDs, you may not see this difference, but then what fun would that be?

Now from what I've read, there is a big different between SLA and both Nimh and the various Li chemistries and not so big a difference between Nimh and Li.

[Raven_darkcloud]

Yup. It comes down to usable capacity. The v/t (volts over time) curve holds out longer. Kinda like lipo compaired to nicad/nimh.

[BarracudaHockey]

Yes the servos are a great choice. Not the best but they were THE servo to have on 50's for a long time. Its what I run on my of my stuff.

[keithstric]

The 9252 servos are great servos. I've been running mine for about a year and a half with no issues.

[vtjeep]

ok seems like everyone is going to 6 volt if u want a bigger battery . what servos should i use for this ? the ones i was looking at 9252 are for 4.8 so no good .. am i getting over my head i just dont want to buy servos again in a year or so because i want to go 6volt .. i looked at duralite package and i can get a package with battery and chargers and switch for like 130 bucks dose that seem rite?now im thinking of 9452's is this a good servo?

[swales]

Don't fret about the 6 volt thing. By the time your skills are to that level you will probably buy another heli. 9252's are the standard.. good, fast, dependable.. As far as the battery... I have run a JR 2700mah NIMH with 9252's all around and a 611 gyro... I can easily fly 3 flights and still have plenty of power left. So going to a 4000mah is not really necessary, unless you plan to fly a gallon of fuel with no recharging. Also you really don't need lipos for the receiver. Why bother with the expense of those and have to buy another charger?

Spend your extra cash on fuel. Most of these forums boast alot of bling and upgrades... but I have seen people do 3D on a stock Raptor with wood blades...

I think most people would agree to put your $$$ in decent digital servos (9252's or the like), then a good gyro (401, 611, Spartan, etc), then on good blades, maybe a metal head.

[vtjeep]

thanks for all your ideas i did get my titan all put together now im doing all the setting up.. i ending up buying 9452 servos and a g770 gyro with a 8900g looks good so far cant waitt to fly when the snows all gone.. i went with a bit higher end servos ..

[Dave]

The S9452 are a great choice but they are designed for 6v. They replace the S9451 which is what I used for cyclic in my Raptor 90. I also used the S9351 on the collective as it has more torque (192 @ 6v) and plently of speed (0.13sec).

The S9452 cost about the same as the S9252 you were considering but they are faster and more powerful and IMHO a better choice for a Raptor 90.

The ONLY disadvantage I have heard of is that they (S9452, S9451 and S9351) use metal gears. Personally I see the metal gears as an advantage as does Futaba as well. I guess some feel that the metal gears wear faster and develope more slop then plastic. I find this extreemly hard to believe. Metal has got to wear better then plastic.

I used the Durlite battery and regulator to power it all. Duralite is not the cheapest but it is the best which is what I believe you are looking for. I used their standard 6v regulator with HD fail safe switch. I then used another 5.3 regulator to step down the voltage for the tail servo. They now have their new HC (High Current) system which includes deans plugs and dual leads to the RX to deliver even more power (just plug the second lead into a unsed channel on the receiver). I used a 7.4v 2s2p Li-Ion for the RX pack as it is redundant. With their new HC batteries it includes deans plugs on the battery as well. This is a great improvement as it get more current to the servos. The high speed/high torque digital servos you are using can draw A LOT of power.

[archiebald]

Here in Japan if you buy a Futaba 9CH or 12FGH, the "best set" radio will come with S9255 servos as standard, whereas the airplane versions come with S9252.

As stated above, Futaba clearly think that metal gears are better for helis. I have flown 4 x 9255 in Raptor No1 aggressively for over 18 months now and there is not one hint of slop in the outputs.

Having said that, I run the cheaper S9252 in my scale Lama and they are fine.