I need help selecting the best Throttle Servo for a DA-50 in a 30% Yak

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I need help selecting the best Throttle Servo for a DA-... - 12/31/2010 7:38 PM

Nitro-Tom

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Hey guys (And Gals for that matter)

I need help selecting the best Throttle Servo for a DA-50 in a 30% Yak.....I remember 2 years ago talking to a guy who flew for Horizon.....the guy had like 4 Giant planes, trailer, etc....and said they tested the DS821 (Which is the standard servo I run)....it's a standard 60 to 90 Sized Glow plane digital servo...but he said they do not recommend it due to vibration......

I need a good Digital for the Choke (Kind of stiff, so it needs good torque) and the throtle....

I fly Spektrum, so I am looking at primarily Hi-tec and JR brand, but am open to anything.....

I run 6V regulated down from 2 Cell Lion (Fromco) for power....

Spektrum AR9100 Rx unit....all JR8611a's on control surfaces, and JR8711 on Rudder

Thanks or the help!!!

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RE: I need help selecting the best Throttle Servo for a... - 12/31/2010 8:57 PM

rangerfredbob

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anything that meets your other criteria and around 100inoz torque with metal gears should be plenty if not fairly overkill... many people use standard servos for throttle, only reason not to use mini servos is vibration

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RE: I need help selecting the best Throttle Servo for a... - 12/31/2010 9:03 PM

Tired Old Man

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Why "the best"? There are a number of them that work extremely well, and none of them are expensive.

Horizon sells servos, and they get a hell of a lot more money for the high end digitals than they do for an 821. The purpose of a factory rep is to sell product, not necessarily tell the truth. 821's will work fine. All you need is speed and resolution that nearly matches the flight servos and a minimum of 48 ounce inches of torque. No mini or micro servos. The 821 easily fits within those parameters.

Everyone gets hung up on having "the best" of everything. They only seem to do this with model planes, and very little else in life. For most of you all that does is make distributors a lot wealthier. We need to accept the reality that most of us will never, ever, be good enough to tell the difference between "the best" and something good enough for the job.

I've seen people with 8611's, 8711's, 7955's, and the latest, greatest high voltage, high torque servos on throttles and chokes thinking they needed 'the best" servo that could fit into the hole. Laughed my a$$ off every time and ended up having to fix a lot of throttle installations where the gears were stripped out of the servo from over driving and failing to adjust the travel adjust at the tx. You don't need a mega dollar or mega torque servo for throttle or choke.

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RE: I need help selecting the best Throttle Servo for a... - 12/31/2010 9:47 PM

rangerfredbob

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figured you'd put in your $.02

, that's what I was trying to get at...

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RE: I need help selecting the best Throttle Servo for a... - 12/31/2010 10:32 PM

Nitro-Tom

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quote:

ORIGINAL: rangerfredbob

figured you'd put in your $.02 , that's what I was trying to get at...

I agree with you guys and I don't....

Follow me here for a minute....I have $3000 into this plane.....Sure I could have built a 30% Yak for $1900 easy.....

But this is NOT a Nitro models or other cheap A$$ anything.....everything on this bird is top notch....That's what I wanted....All Fromco power, 4 Rx units, Carbo gear, etc.etc.etc.....

Did I pay too much for the DA-50? Sure, some will rant all day long on that alone, and in many ways they are right, the DLE-55 (Especially now-I bought this 2 years ago-Been Busy

) would do a fine job at a much happier price....

But now that I have done this, I figure not to mess around....saving a few bucks on the last 2 items....

Will I buy a HV Super Fast .06 second JR servo for this throttle, heck no! That is only going to make a difference in a Heli.....this freaking weed eater motor is so slow in throttle response once the butterfly is open it does not matter.....A.K.A overkill.......

But I do want a Really, really good one (Maybe I should not have said BEST in my original post?)

And while I agree the DS821 is fine....in fact I used that on the bench installing the servo's and seting up the control arms, etc....it is not metal gear so it is out....due to the motor rocking and rolling with vibration.....

I once saw a guy with a throttle servo go bad in flight, not wide open, just stripped the gear or failed at 3/4 and he flew around for 10-15-20 minutes when all of a sudden his TX battery went low....he was freaking out,etc.....and eventually got down in one piece but almost lost the plane.....

I do NOT want to be THAT GUY! I just want a good reliable servo, metal gear, that is overall good (And this criteria usually points to Hi-tec) so I am posting for help with model numbers.....basically I do not know their product line well at all....

The JR equivlent is like $90, so I was hoping to get one in the $60 range....and for the choke, I want a really, really good one, so I can use it in other applications in the future if necessay......

I do not mind a little overkill here so I can use these servos later on when I sell this plane and move on, etc..

That's why I got the 8611A's and the 8711....so when I move up to 100CC and 35% I can move these over, and do not have to buy all over again....

I must have a freaking 5 Gal bucket of DS-821's at this point.....

Thanks for the help guys and keep the ideas comming!

Happy New Year!!!

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RE: I need help selecting the best Throttle Servo for a... - 12/31/2010 10:38 PM

Nitro-Tom

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Not really getting the response I wanted with this thread....hmmm..

Maybe I should have titled it "What Throtle servo did you use in YOUR 30% Giant Scale Gas plane?"

Live and learn.....I am still young at the RCU thing compaired to many.....

If you guys can let me know what make and model servo you have used in the throttle/choke on your 30% Gas projects (Past/Present/Whatever) that would be great....

Happy New Year!

Peace out!

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RE: I need help selecting the best Throttle Servo for a... - 12/31/2010 10:54 PM

Tired Old Man

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Let me put it another way. I don't generally fly anything under 35% unless it's a foamie. I am currently flying a 2.6m Comp Arf Yak in the fantasy scheme, using a BME 116 up front. No power distribution systems. Retail value for all of it: about $5,000.00. The airframe alone is over $1,700.00 before putting anything in or on it.

I also have a 41% Giles 202 with a Brison 6.4 up front. No power distribution system. Retail value for all of it: about $3,000.00.

Also in the hanger is a 46% Ultimate with a DA 150. This one has a power distribution system because 15 servos are a little difficult to feed without a whole lot of Matchboxes. Retail value: about $6,500.00.

There is one exception to small planes with a 74" span Katana using a DLE 30. That one uses Hitec 645's on everything.

All of the above with the exceptioon of the Katana use upper end servos for the flight surfaces. For throttles they are using a JR 4721 analog coreless with nylon gears only because they are fast and precise. That's more money that I wanted to invest in a throttle servo. Had I any more of the old Hitec 5945's they would have been in there instead. For 50CC planes, and I have had A LOT of them, I found the 821's to be just fine until I ran out of them and had to dig through my servo inventory to avoid buying more servos. I've also used Hitec metal gear mini servos without any issues, but I learned how to set up throttles, radios, and servos a very long time ago. FYI, I don't fly glow, ever, so all the servos are on gas engines. I even have a DA 100 set up with a Futaba analog, nylon geared, mini servo. No problems but the set up is unique with very short linkage. I set up the same size planes for other people and nobody has had a complaint yet.

The 821's will be just fine. I'm not sponsored or provided product so I use what experience has shown to work well, not what some name flyer is paid to tell me. Don't let all the flash, bling, and big names dictate what you use. Use your head instead and you'll keep enough money in your pocket to build a $1,700.00 plane that flies as good or better than one more expensive. My $0.02.

< Message edited by Tired Old Man -- 1/1/2011 1:05 AM >

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RE: I need help selecting the best Throttle Servo for a... - 12/31/2010 11:41 PM

rangerfredbob

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I wasn't trying to offend, TOM has a BUNCH of experience, he's a little blunt but generally knows what he's talking about. Sarcasm doesn't show well over the interweb...

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RE: I need help selecting the best Throttle Servo for a... - 12/31/2010 11:48 PM

KenLambert

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I use 8411s on all my throttle , if you hover and do 3D you don't want your throttle servo going out it would be as bad as an elevator going bad.

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 12:01 AM

Nitro-Tom

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quote:

ORIGINAL: KenLambert

I use 8411s on all my throttle , if you hover and do 3D you don't want your throttle servo going out it would be as bad as an elevator going bad.

Good point................ as this JUST happend to me on a glow bird (Dead Stick) and I was LUCKY I was up high enough.....barley

.........dead stick landed nicely into the wind without a scratch....however if I was 20 feet lower.....it would not have been so good.......

I once saw a $6K comp arf go in because a wire came off the fromco regulator.......powering the ignition....when he was down on the deck....getting it done!...
just the wrong thing happend at the wrong time.....

I like the looks of the 8411.....

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 12:09 AM

pdm52956

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If you're looking for a "higher end" servo for your throttle, have you considered the Spektrum A6030? I put a couple in an 88" Extra to give them a shot and I kind of like what I'm seeing with them.

Let's face it, 8411 has about 188 oz/in while the A6030 has about 278 @ 6V. I think I saw the 8411 at about $115 on sale and the A6030 cost me $85 not on sale.

Just thought I would mention them. Good luck.

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 1:19 AM

Tired Old Man

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Not much difference between an 8411 and a 4721 except one is digital and the other analog coreless. Aside from that they are the same. Some people get antsy about nylon gears but the gears are rerely the problem. It's the set up that makes or breaks an installation. Take that Fromeco regular for example. Not having the regulator and using a 4.8v battery would have eliminated that failure point. So would have securing the when wires using the regulator.

My point is the cost (equating to best?) of an item does not assure success, reliability, or longevity. Good equipment goes a long way to making that happen, certainly, but even more it depends on the person that installed the stuff and how that was done. Do things right and you won't have failures of electrical equipment. I certainly don't have those issues. Do things wrong and everything can take a chit on you when you can least afford for it to happen. Pouring money into something does not make it good. BTW, if you set up the throttle linkage right, tune the engine, and build in a little curve, that slow throttle response will become very quick and accurate.

There is one caveat. If you are performing 3d or aerobatics down so low that if something fails you can't make a landing, don't blame the equipment. The crash itself will have been caused by poor pilot decision making. With gliding altitude the plane will generally be able to make a good landing. Equipment failure does not assure a crash. Only you can do that.

Case in point. I was at the Huckfest about a month ago and watched some 3d newbie experience an engine failure at speed. Cause unknown and doesn't matter. He was 1/2 a mistake high and could have traded speed for altitude and made the runway. Instead he extended and bled off airspeed down low, and while still having enough speed to turn for the runway he elected to pull hard (vertical) up, stalling the plane. Ya'll know what happened from there. Pilot decision caused a lot of damage to the plane that did not need to happen.

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 5:26 AM

p51Dpony

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Not sure about what your transmitter requires, but I know with some futaba's if you want to run "fast frame rate" the channels 1-6 or something must be digital servos, other wise must go to default frame rate, I think it's 14ms vs the fast rate of 7ms. On my 35% yak am running a std torque digital servo and on giant stinger we're running std resin gear servo with nylon clevis and wood control rod, I always remove the throttle arm spring on engines if so equipped so the radio and servo don't have to fight spring, just make damn sure all linkages and screws have reassurances built in (lock-tight, glue on servo screws or servo case to prevent vibration..etc). Some persons are big on leaving the throttle arm spring in place. Without the throttle arm spring the carb is the lowest resistance of any airplane part and a std servo is plenty, my yak is top of the line everything too and is a joy to fly. Happy flying.

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 6:01 AM

Nitro-Tom

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quote:

ORIGINAL: pdm52956

If you're looking for a ''higher end'' servo for your throttle, have you considered the Spektrum A6030? I put a couple in an 88'' Extra to give them a shot and I kind of like what I'm seeing with them.

Let's face it, 8411 has about 188 oz/in while the A6030 has about 278 @ 6V. I think I saw the 8411 at about $115 on sale and the A6030 cost me $85 not on sale.

Just thought I would mention them. Good luck.

Sweet, I got the Spektrum 2011 catalog at the LHS this Xmas....this bad boy looks just right at about $85.....I was trying to get better than the $29 DS821 (Metal Gear Primarily) but now I look at the A6030 and it remindes me, the dual Ball Bearing will help with the Choke Servo....alot of torque and work there to move the butterfly open, but it will be good as long as end points are set.....and both the A6000 and A6010 are brushed....I prefer the coreless......so far the A6030 looks good....now I just need to find the Hi-tec and JR equivlent and pick one....

SO..... I also found the Heli Servo, little less torque, H6040....about $10 less, pleanty of torque at 167oz-in and lightning fast (overkill) .08 Sec.......or the H5010 in a mini but I do not want to go mini....

Also I have my first plane with Hi-tec servos , working out well so far, not big on the programmer, but lots of guys say Hi-tec is top notch and I find generally a little less than JR....

Any one know the equivlents for Hi-tec to the above A6030 or H6040? Metal gear, Digital, 6V, Coreless, about 150oz or better?

Thanks again guys for all the help, the posts are great........what else can I be doing until it quiets down and we can get some sleep

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 6:11 AM

wesaysoracing

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hi torque servos on the throttle? i hope no one tells my 50 oz-in. torque nylon geared standard servo that it wont work for the throttle any more

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 6:12 AM

apalsson

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Tom, I cannot help getting the feeling that you had already made up your mind regarding the throttle servo but kept asking till you got an aswer that supported the decision you had already made.
The A6030 is some 20Kg torque, all to move a carburettor butterfly arm that basically has no tension on it.
Believe me, any good 3 - 5Kg servo with a good resolution is ample for the throttle on any of the small gassers we use.

T.O.M. is undoubtedly one of the most experienced small engine person that frequents these forums and getting frustrated if his answers don't match with the ones you had been hoping for is of little use.

If you are hellbent on wasting your money on an overkill servo for your engine, mate go ahead, it's your $$$. Please just don't argue the toss over it
The A6030 would do just fine for the rudder in your 30% YAK

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 6:25 AM

Tired Old Man

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quote:

ORIGINAL: p51Dpony

Not sure about what your transmitter requires, but I know with some futaba's if you want to run ''fast frame rate'' the channels 1-6 or something must be digital servos, other wise must go to default frame rate, I think it's 14ms vs the fast rate of 7ms. On my 35% yak am running a std torque digital servo and on giant stinger we're running std resin gear servo with nylon clevis and wood control rod, I always remove the throttle arm spring on engines if so equipped so the radio and servo don't have to fight spring, just make damn sure all linkages and screws have reassurances built in (lock-tight, glue on servo screws or servo case to prevent vibration..etc). Some persons are big on leaving the throttle arm spring in place. Without the throttle arm spring the carb is the lowest resistance of any airplane part and a std servo is plenty, my yak is top of the line everything too and is a joy to fly. Happy flying.

Not to be arguementative, but word of caution. Don't do this. That spring helps maintain the throttle plate position inside the carb body, keeping wear to a minimum. Too many people that have removed the return spring have experienced stiuck or sticky throttle plates caused by wear induced from side to side motion of the throttle plate. Some engine manufacturers void the engine warranty if the return spring has been removed.

As for the radio or servo fighting that spring, it's not an issue. If you have a 48 ounce inch servo you have more than enough to easily overcome the spring tension. Once a servo achieves the pont where it stops moving there is very little current draw. About .1 amp with a digital and less for an analog. A servo draws the most current at the beginning of it's motion and rapidly drops off after that unless stalled, and that only happens when the travels are excessive or binding occurs. Use a volt and amp meter sometime to verify that. All of the regular sized, and most standard mini sized servos on the market have no problems, even in the long term, with carb throttle return springs. In well over a thousand uav engines no throttle servo has ever failed due to the throttle return spring, and those are smaller servos than what most of you would contemplate using,and those servos work harder than yours ever will.

Another factor is throttle linkage. If it fails the throttle will remain at the last position before failure unless something disturbs it. Keeping the return spring will permit the carb to retun to a closed position if the linkage fails.

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 7:24 AM

KenLambert

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I didn't mean for the tourq , I was talking about using a good servo V a cheap servo. ( has anyone ever had a servo go bad?) I run Hitec 7955s on all surfaces but the 8411 servos are good for throttle ( my opinion on my airplanes) I don't mean a wire coming loose, I am talking the servo quits , burns out. a good one is less likly to do that than a cheap servo.
As far as curve if you setup the linkage right you don't need curve that is why I use the long throttle arms .
I also unhook the spring but leave it on the shaft to prevent slop.

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 8:20 AM

Tired Old Man

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quote:

ORIGINAL: KenLambert

I didn't mean for the tourq , I was talking about using a good servo V a cheap servo. ( has anyone ever had a servo go bad?) I run Hitec 7955s on all surfaces but the 8411 servos are good for throttle ( my opinion on my airplanes) I don't mean a wire coming loose, I am talking the servo quits , burns out. a good one is less likly to do that than a cheap servo.
As far as curve if you setup the linkage right you don't need curve that is why I use the long throttle arms .
I also unhook the spring but leave it on the shaft to prevent slop.[/quote]

If one feels the need to bypass the throttle spring that's the right way to do it.

Servos do go bad, it really doesn't matter how "good" they are. About the most you should ever expect to get out of a servo is somewhere around 200 hours. If it's used heavily anticipate less, much less. They are not a made to last forever item.

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 10:06 AM

pdm52956

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quote:

ORIGINAL: apalsson

The A6030 is some 20Kg torque, all to move a carburettor butterfly arm that basically has no tension on it.
Believe me, any good 3 - 5Kg servo with a good resolution is ample for the throttle on any of the small gassers we use.

Yes, in my opinion it is overkill for a throttle and/or choke, but if the OP is wanting to go there then why not mention them. I brought them up because they aren't well known, at least where I am, and they certainly have specs that stand up to his thought about a really good servo. Good price for what you're getting too. It is afterall his choice right?

The throttle can be as important as any other servo depending on the flying style and the desired results. Me personally, I've got the A6030 on my 50cc elevators because I've had issues with those surfaces in the past and decided to try something different this time. My throttle has a 5625 Hitec on it and I run a standard servo for my choke. The 5625 has more than what I need and at roughly $45, it's well within budget.

Cool thing about equiping any plane..........to each his own.

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 3:07 PM

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quote:

ORIGINAL: wesaysoracing

hi torque servos on the throttle? i hope no one tells my 50 oz-in. torque nylon geared standard servo that it wont work for the throttle any more

Yeah, believe me, I do NOT want to spend $80 on a choke servo, all I want is metal gear, 6V, Coreless, and I am wondering if Digital is a bad idea for the choke, as it will always be trying to center (Drawing Current, etc).....the butterfly on my DA-50 is hard to move, and has this hump to "Get over" when opening and closing....

Of course I will set the end points, etc...and test it.......

This is the reason I started this thread.....to see what model servo's other have used in these area's with success.....

I also am sick over spending $80 for a high torgue servo for the throttle, when it has basically no resistance, I removed the return spring at the recomendation of DA.....they said it was fine to do that..

I am sure a 25oz servo would do fine here......Guess I just would like full sized metal Gear.....

So maybe a Spektrum A3040 which is fast (.10sec) and metal gear, coreless, 6V, and seems to cost about $25.....only concern is it is sub micoro and said it is used for Park flyers and "Slow" planes....

Guys I apreciate all the post and please keep them comming....I just don't want to make a bad move on this last part of this bird.....

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 3:21 PM

Nitro-Tom

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quote:

ORIGINAL: apalsson

Tom, I cannot help getting the feeling that you had already made up your mind regarding the throttle servo but kept asking till you got an aswer that supported the decision you had already made.
The A6030 is some 20Kg torque, all to move a carburettor butterfly arm that basically has no tension on it.
Believe me, any good 3 - 5Kg servo with a good resolution is ample for the throttle on any of the small gassers we use.

T.O.M. is undoubtedly one of the most experienced small engine person that frequents these forums and getting frustrated if his answers don't match with the ones you had been hoping for is of little use.

If you are hellbent on wasting your money on an overkill servo for your engine, mate go ahead, it's your $$$. Please just don't argue the toss over it
The A6030 would do just fine for the rudder in your 30% YAK

Not trying to argue or get anyone upset here.....and I do Apreciate Tom's knowledge and experience.....which is why I post here and ask for reply....so first off, Thanks to all for posting!!!!

I am NOT set in my mind and looking for support, we have a group of local guys at the filed for that

Our "chearing section" is second to none

I am looking for: (I am learning here - revamped requirements)

I need a choke servo that is:
6V
Coreless
Full Size prefered
High Enough Tourqe to move the butterfly on a DA-50
Metal Gear to handle the vibration (I know I MAY not need this, but piece of mind is good)
Not sure on Digital - do NOT want it using MaH trying to center....if the chock is pushing back....so analog may be better here (Comments)

I need a Throtle servo that is:
6V
Coreless
Full Sized prefered
Fast enough to not be the slow point in the curve...for throtle response
Metal Gear to handle the vibration (I know I MAY not need this, but piece of mind is good)
Digital prefered (For all the same reasons)

Is that better requirements.....?

And not that I am taking a pole here....but most seem to have thrown a cheap nylon gear servo on and called it a day.....

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RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 3:32 PM

Nitro-Tom

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quote:

ORIGINAL: Tired Old Man

quote:

ORIGINAL: p51Dpony

Not sure about what your transmitter requires, but I know with some futaba's if you want to run ''fast frame rate'' the channels 1-6 or something must be digital servos, other wise must go to default frame rate, I think it's 14ms vs the fast rate of 7ms. On my 35% yak am running a std torque digital servo and on giant stinger we're running std resin gear servo with nylon clevis and wood control rod, I always remove the throttle arm spring on engines if so equipped so the radio and servo don't have to fight spring, just make damn sure all linkages and screws have reassurances built in (lock-tight, glue on servo screws or servo case to prevent vibration..etc). Some persons are big on leaving the throttle arm spring in place. Without the throttle arm spring the carb is the lowest resistance of any airplane part and a std servo is plenty, my yak is top of the line everything too and is a joy to fly. Happy flying.

Not to be arguementative, but word of caution. Don't do this. That spring helps maintain the throttle plate position inside the carb body, keeping wear to a minimum. Too many people that have removed the return spring have experienced stiuck or sticky throttle plates caused by wear induced from side to side motion of the throttle plate. Some engine manufacturers void the engine warranty if the return spring has been removed.

As for the radio or servo fighting that spring, it's not an issue. If you have a 48 ounce inch servo you have more than enough to easily overcome the spring tension. Once a servo achieves the pont where it stops moving there is very little current draw. About .1 amp with a digital and less for an analog. A servo draws the most current at the beginning of it's motion and rapidly drops off after that unless stalled, and that only happens when the travels are excessive or binding occurs. Use a volt and amp meter sometime to verify that. All of the regular sized, and most standard mini sized servos on the market have no problems, even in the long term, with carb throttle return springs. In well over a thousand uav engines no throttle servo has ever failed due to the throttle return spring, and those are smaller servos than what most of you would contemplate using,and those servos work harder than yours ever will.

Another factor is throttle linkage. If it fails the throttle will remain at the last position before failure unless something disturbs it. Keeping the return spring will permit the carb to retun to a closed position if the linkage fails.

Wow.

DA Support told me to take off the return spring......and I mean pop it over to the side, not "Take it off" (That would have voided the Warranty) but they told me to pop it over the arm and remove the resistance for the butterfly to close.....now your expireience is obviously extensive....and I feel I should put it back on.....as there is not really enough return resistance to make the servo work....but like you said, if the linkage failed or the servo failed, it would be nice to have that return to idle settings...and I agree with what you say about the servo current....that spring will not make an 80oz servo sit there and draw current.....it may make a sligh buzz.....but heck, this is a 3D bird (Yak) so that thing will not be sitting in one place for very long on the average flight....

and after all, during the manufacturing of that engine they put it on there?

Must have been for a reason.....never thought it would hold it "Center" in the carb throat......

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Post #: 23

RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 3:41 PM

Nitro-Tom

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quote:

ORIGINAL: KenLambert

I didn't mean for the tourq , I was talking about using a good servo V a cheap servo. ( has anyone ever had a servo go bad?) I run Hitec 7955s on all surfaces but the 8411 servos are good for throttle ( my opinion on my airplanes) I don't mean a wire coming loose, I am talking the servo quits , burns out. a good one is less likly to do that than a cheap servo.
As far as curve if you setup the linkage right you don't need curve that is why I use the long throttle arms .
I also unhook the spring but leave it on the shaft to prevent slop.

Holly Mackrel! I just looked at the price on a 8411 and it is $125

Ouch!

Another reason I started this thread (And I APOLOGIZE for not comunicating better here, I am not the best at that) but.....I have a hard enough time spending $80 on a choke or throttle servo....again, I do not want to cheap out on a $3000 bird here....but darn, can I get a little better deal here

I paid like $115 for my "Other servo's" and like $120 for my 8711 for the rudder, knowing I can move them to a 35% bird later, etc.....

But I was hoping to find something to fit the bill without sending over another $200 here for choke and throttle

I mean if I was just going to be waistefull with money and overkill, I would just put a pair of 8611's on here and be done....but that even has a Nylon B1 gear, which may be fine for the aileron, but this motor vibrates alot.....all gassers I see do that.

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Post #: 24

RE: I need help selecting the best Throttle Servo for a... - 1/1/2011 3:50 PM

Nitro-Tom

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quote:

ORIGINAL: pdm52956

quote:

ORIGINAL: apalsson

The A6030 is some 20Kg torque, all to move a carburettor butterfly arm that basically has no tension on it.
Believe me, any good 3 - 5Kg servo with a good resolution is ample for the throttle on any of the small gassers we use.

Yes, in my opinion it is overkill for a throttle and/or choke, but if the OP is wanting to go there then why not mention them. I brought them up because they aren't well known, at least where I am, and they certainly have specs that stand up to his thought about a really good servo. Good price for what you're getting too. It is afterall his choice right?

The throttle can be as important as any other servo depending on the flying style and the desired results. Me personally, I've got the A6030 on my 50cc elevators because I've had issues with those surfaces in the past and decided to try something different this time. My throttle has a 5625 Hitec on it and I run a standard servo for my choke. The 5625 has more than what I need and at roughly $45, it's well within budget.

Cool thing about equiping any plane..........to each his own.

ok so now I have Hitec 5625 on my radar....and I agree with the new Spektrum Servos.....they are less known and look really good, let's face it the DS-821's have done me well for 4 years on the 40-60-90 sized glow birds.....

So the 5625 looks like a good choice for the throttle, metal gear, 6V, good speed and torque, so the only "Catch" here is this is not coreless? (It says 3 pole) and overall for reliability do I really care?

Like everyone has said this is not the Elevator servo....

Can you define "Standard Servo" on your choke?

Thanks again for all the info!!!!

Oh, BTW: Happy New Year!!!!

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