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Oct 19, 2002, 11:09 PM
Registered User
Help!

Help! My wing servos stick out of their bays!


Help! I'm building a relative thin-wing sailplane and have had some problems mouting the wing servos!

The manufacturer recommended Hitec HS-85BB+ and HS-85MG+ for the wing servos, which I purchased.

The problem is that the aileron servos sit about 3/16" out of their servo bays and the flap servos sit about 1/16" out of their bays. Will this present a problem with flight dynamics? The supplied covers assume a flush fit. If I make a custom cover, or use a sticker, will this work?

Any suggestions?
Last edited by Sanman; Oct 20, 2002 at 04:04 AM.
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Oct 20, 2002, 03:00 AM
Just a plane Junkie
I have the same thing going on with a plane I'm building using the recommended servos (hs-55's). I'm going to cover them with Ultracote or some sticky-backed Sky Shine (like a sticker).

I don't think it will affect performance noticeably. If you have 200sq inches of wing area (im guessing this amount for my 1.5m), the servo area would represent 1% or less of the total. Then say it makes that area 30-50% less efficient... It seems quite insignificant compared to the other flight performance variables.

I'm no aeronautical engineer though
Oct 20, 2002, 04:07 AM
Registered User
The thinnest servos are from Voltz and Multiplex and are about 10 or 11 mm thick. They are on the pricey side of the HiTech's. Just tape over the servos and don't worry. You probably won't notice the very small degradation in performance. When the model is on the ground, keep it right side up so the servo bumps won't show. After a while you won't even think about it much.
Last edited by Ollie; Oct 20, 2002 at 05:31 AM.
Oct 20, 2002, 12:33 PM
An Original!
Don't forget the new HS-125 and HS-5125 wing servos. Also 10mm thick, good torque and new hibrid gearing. Servo city has them in thier specials section for $74.95 and $119.95 respectively.
Oct 20, 2002, 06:59 PM
Registered User
...or let them stick out and put plastic covers on them that provide for this. Hobby Lobby has them.

http://www.hobby-lobby.com/servomount.htm and go to the bottom of that page.

Unless your one of the top 5% (and if you were, you wouldn't be posting this here), you will not see any affect on the performance of the plane.

dd.
Oct 20, 2002, 07:09 PM
TLAR Black Belt
ejett's Avatar

Hitec Wing Servos


The pricing that was quoted to you from servocity is for pairs of servos. That would put the 125's at about $35 ea. and the 5125 digitals at about $60 ea.

The 125's are what I'll be using on my next project.

I'm not good enough yet to appreciate the extra perfomance of the 5125's.