which servo's for a 3m performance glider

[invrtd]

I was wondering what servo's people are using for there open class 3m gliders. I was looking at HS-85mg's but don't want to be too cheap on such an expensive glider. Are and will the HS-85's hold up or is it better to spend a little more money for a better servo.

[MDM]

I was wondering what servo's people are using for there open class 3m gliders. I was looking at HS-85mg's but don't want to be too cheap on such an expensive glider. Are and will the HS-85's hold up or is it better to spend a little more money for a better servo.

HS-85MG are good servos, i use them on all my slope stuff. I would use them for flaps on a TD plane, for the tail and aileron they may develop too much slop over time... They are also heaver then a nylon servo for these surfaces.

Check out the JR351/HS125MG or HS5125MG/DS168 for wing servos and something like a JR341 for the tail surfaces. I have one 3m with all JR351 and one with a combo of DS168 and JR341. The second one is defiantly lighter.

For some real cool servo frames, see: http://servoframes.com/

Example:

[invrtd]

I think I will go with the jr 341's for everything but the flaps. I just wonder thought if you compare the specs of the hs-85bb non mg to the 341's. The HS85's are faster. I am newer to gliders and just wonder if speed is that big of a deal. I fly mostly heli's and speed is something we look for, but at the same time I don't put cheap servo's in my $2,000 heli. But heli's test servo's with high torque and vibe's.

[MDM]

I would me more concerned with slop, the kinds of speed needed for a heli tail / gyro are not needed. You want consistent centering and no eventual slop when the metal gears wear. You do want metal gears on the flaps.

[aeajr]

You have not said what plane you are flying. That would help.

I have HS-81 MGs in my Airtroncis legend on the flaps and on the ailerons. However I have plenty of room. If you are flying a thin winged plane you may need a wing servo in order to get a good fit in the space.

The 85s are larger and stronger than the 81s. In fact the 85s are about as strong as a standard servo, as I recall.

By high performance do you mean that you expect to be doing a lot of high speed aerobatics with the plane? If that is the case you might consider digital servos as they tend to have more holding power than the analog servos like the 81s and 85s.

For the flaps, speed is not really a concern unless you plan to have the flaps follow the ailerons, then I would suggest you match the seros on the flaps and ailerons. Not a critical issue, but just a good practice. Also, if you use all the same servos, then one or two spares will cover you if you damage one at the field.

[MDM]

Some wings are too thin for mini's so you then must use the flat (like a HS125) servo. Yes, what do you have for a plane ?

[flyingdogtwo]

Being a soaring club you hear a lot of what works well in 3M+ planes.

http://horizon.hobbyshopnow.com/products/description.asp?prod=JRPSDS368

[invrtd]

I have not purchased a plane yet. Still deciding on which one. I have looked at the legend from Dream Catchers for the price. However, I am looking at the Laser from NEsail too. I currently am flying a 2m RES with a buddy who has a nice 3M ship. He says I fly well enough to graduate to a better bird. As I have stated I fly RC heli's and real heli's for the Florida Army National Guard. Been flying RC for over 11 years. I will be moving back to florida in July and they have glider clubs in several cities and competitions about once a month somewhere. I would like to compete with a nice 3M+ ship. My 2M RES just does not penentrate the wind at all. I would like to find a ship that has good performance for a reasonable price.
aeajr sell me on the legend. Dream catchers has a kit with fiberglass/kevlar fuse for $209.00. I would have to build the wing and tail but don't mind that. How does the legend compare with some of the other birds out there. And if someone has a laser sell me on it. I know they are 2 different classes of gliders in terms of construction, but how do they fly? What ship out there has the best performance for the best price.

[aeajr]

I have no reason to sell you on the Legend. I am pretty new with it. It is a heavy plane at 80+ ounces which will make it more stable in wind. It also has a reputation for being a fairly stable ship.

What 2M RES are you flying. I fly a Spirit 2M RES and a Sagitta 600 2M RES.

Have you tried adding ballast to your plane to help penetrate wind?

I was flying the Sagitta in 15-20 MPH winds on Saturday but I had 5 ounces, or about 12-14% of the plane's weight in added ballast right over the CG. Made a HUGE difference in my abiltity to penetrate the wind.

I have flown my Spirit in 12-15 MPH winds with about 3-4 oz of ballast.

Unballasted, the planes were virtually unflyable under these conditions.

[invrtd]

I have the cirrus 2m from hobby people. It flies great and is very stable. The only thing I did is moved the CG back from what the instructions said to get better lift. I had to put alot of up trim in the glider with the stock CG. The next thing I plan on doing is taking out some of the wing incidence by putting a small shim under the back of the trailing edge. This will make it a little less stable but will give the glider better performance and show lift better. I think I will have to build a small ballast box over the CG for those windy days. I am also working on a spirit 100 but like I said, I am looking for a nice 3m+ bird. I have flown my friends 3m ship and there is so much difference in all around performance. Especially being able to reflex the wing to get back up wind.

[aeajr]

You will be surprised how adding some ballast, about 7-15% of the plane's weight, will improve your windy day handling and penetration into the wind.