TIA

I have two Hitec HS-85mg servos and two more powerful higher torque Hitec HS-225mg servos.

I am wondering anyone's opinion of which servos I should put where?

225mg servos in the wings or in the v-tail?

Wing or tail group, does one control surface necessitate a more powerful servo than another?

TIA.

BUDMAN27

Personally I would put the more powerful two on the tail.

daven

My Feedback: (1)

For 424, you can get by with the 85's on the tail if everything moves smooth. There are a few people using them on 428 planes, but I personally would not recommend it. I would not use an 85 on aileron.

DMyer

My Feedback: (2)

HS-85 are only good for throttle... the HS-225MG(Metal Gears) are OK for 424 ailerons and tail feathers... but most people use the plastic gears instead of metal because the metal gears will wear and develop slop. IMO I would not use the Hs-225 on a 428 plane due to the time and/or $$$ investment it is a false economy to save $$$ on the radio equipment. One Hitec servo failure(I have seen them) on a 428 = one heck of a lot of quality JR/Futaba stuff!

Dan

TIA

I've heard that before that the metal gears develop slop over a short amount of time, not only that but something about a gear-pin slotting the case? Well, there's always ebay.....

So I'm now thinking of putting something better in the plane rather than the mg's. What servo should I be shopping for/which servos do you guys run? Do they have ro be digital?

Thanks again for the great help!

Ron.

Airbike

My Feedback: (6)

Ron,

I think that two HS-85 is ok for the V-tail but one HS-85 is not allowed for the aileron as it only has 2 mounting screws. Somewhere in the rules, there is a requirement for 4 mounting screws for any servo used on a primary flight surface. I guess the v-tail is allowed as it has a semi-redundancy with 2 servos.

I'm using HS-85MG on Rud/elev/each aileron on my Wildhare LR-1 w/SJ.50 and it's holding up so far, but I don't fly it often. So torque wise, I think it is sufficient for 424 with a TT.40 but wouldn't be legal.

Dan

HighPlains

My Feedback: (1)

All brands of servos fail. Usually has more to do with the installation than the brand. I've read many posts over the years about how this servo sucks or that one will not work. So I put 5 of the weakest, gear stripping servos I had into a Nelson powered 428 quickie and went flying and racing. After 50 - 60 heats, I lost the airplane to a mid-air. The wing survived, so I built another fuselage, this time powered it with a ST G40 with a Nelson pipe and sport flew it for another 10 hours or so until I cartwheeled a landing. Through all of this, these cheap servos continued to work fine, never stripped a gear.

Now you might wonder what kind of cheap servo holds up to all control surfaces on a 170 mph quickie? A Hitec HS-80. Since then, I built another with HS-81 on all controls. In both cases, I used two on ailerons (as per the rules). The main short coming of this type of servo is the lack of a BB output, so after 5 or 6 hours, they start to wear out the servo case top. The HS-85 should be fine since it does have the BB on the output shaft.

All that being said, you must use mechanical advantage to do this when you set up the linkage. A small servo will not tolerate a poor servo installation . You have to have the servo output holes as close to the center of rotation as possible, with long arms on the control surfaces. The radio must be programmed to full servo rotation to avoid problems with torque, centering, and slop in linkages. I only did it for a test, and do not recommend it.

BUDMAN27

Highplains thank you for the info. I fined vary useful.

daven

My Feedback: (1)

I'm not saying it can't be done, but I wouldn't recommend it either.

Eventually, every servo will fail. Some sooner than others, I would prefer a little overkill when it comes to a 170+ mph bullet.