Servos and Extensions

When building a large R/C aircraft, chosing the servos is one of the most important decisions you will make. It involves  how well the plane flies, how much it costs, and can affect how long it lasts.

Servos are a big expense because many servos are used in a plane, they usually make up about 30% of a R/C plane's cost. Selecting the proper servos involves several factors;

How much can you afford to spend? What type of flying do you plan to do? What will you do with these servos after you are done with this plane? These are all important questions.

We at Wild Hare have tried to simplify this choice somewhat with a few simple rules;

Coreless servos are faster and more accurate, and a lot more expensive. Servos with a cored motor are perfactly acceptable for most applications.

Metal gears are absolutely necessary for any plane bigger than 75" wing span or 12 lbs.

Hitec Karbonite gear servos are acceptable for smaller planes, and Karbonite gears are more accurate with less slop than metal gears, so use them when possible but never on a big plane.

Plastic gear servos are pretty much useless on any control surfaces. OK on throttle or choke.

Wild Hare sells Hitec servos as our primary line of servos. We also sell the HD Power line of servos. These are very good quality and are economical. We sell selected models, not the entire product line. We sell the models that we have tested and used and which have a good record. We do not sell the entire HD line of servos because of some variability in quality on certain models.

If you plan to keep servos and move them from plane to plane, buy the best ones you can afford. Titanium gear servos will last the longest, like the Hitec 7955TG. They are overkill for most of what Wild Hare sells, but are a good value if you plan to use them for a long time.

You will usually need more power on your rudder than on the other surfaces.

Hitec servos come with very good Karbonite arms which are strong enough for most applications.Aluminum servo arms are very nice, and are necessary on larger planes if you do not have the Karbonite arms available.

 Hitec uses a different size and spline of shaft from HD. HD uses the same arms as Futaba. Be sure the arms you use are the correct ones for your servos, it's easy to get them mixed up.

All listed servos are digital and ball bearing unless noted otherwise.

Remember to scroll down to see our servo packages as well!

Description	Torque at 6.0v inch/ounces	Gears	Suitability
Hitec  7955TG	330 oz.	Titanium	Any large scale plane any size	Hitec's top of the line reasonably priced servo, excellent for anything with long life titanium gears, coreless motor and heat sink.
Hitec 7985MG	172 oz.	Metal	Large scale planes	Excellent quality precision servos, metal gear coreless motor, use in pairs on a 100cc aileron.
Hitec 5485HB	89 0z.	Karbonite	30cc planes	Good precision servo for smaller gas planes, not real expensive, also makes a good throttle servo.
Airtronics 94851	200 oz.	Metal	any large plane	The Airtronics 94851 is an excellent value, centers well, has plenty of torque and is relatively inexpensive. Needs metal arms.
HD 9110	145 oz.	Metal	medium size planes	The HD 9110 is a good value servo where maximum torque is not essential, is great for 50cc planes.
HD 4180	59 oz. approximately	plastic	decent servo for small surfaces and throttle	The 4180 is a premium digital "standard" servo. I have used them succesfully on the 73" "Baby" Edge and Extra. Good for throttle also!
HD1501 Analog	270 oz.	metal	large planes	The 1501 is a very high torque analog servo, is great for applications where strength and low cost are important.
HD 3001 analog	61 oz.	plastic	small glow planes, throttle	The HD 3001 is an economical "standard" servo similar to the HItec 425 or 422 inexpensive good quality servo.
Extensions				Twisted wires, 22 ga. with JR male and Futaba female, "universal" will fit with any servo or receiver. Available in lengths of 6" 12" 18" 24" and 36".	Click for larger photo.
Servo arms	MPI anodized aluminum			Available for Hitec and HD/Futaba in lengths 1", 1.25", 1.5" plus double offset arms 3" and 4".	Click for larger photo.