Glider Servos
#1
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Glider Servos
I plan to order a kit of a 110" wing span glider (approx. 5-6 lbs) and I can not find any info on the size of servo (small medium or large) or torque requirements. I plan on spoilers and ailerons. I sent an email to the builder of the kit and got a real sarcastic reply. I am new to gliders and any help would be appreciated. Would the Hitec HS-225MG (54oz-4.8v-66oz-6v) servo's do the job?
#3
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RE: Glider Servos
My 118" span scratchbuilt 1/6 scale 1932 BS2 'Balestruccio' will use HS-125MG servos which should be more than adequate for straight and level scale thermaling flight.
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RE: Glider Servos
The answer is that it depends... I fly 99" to 130" gliders that never see above 40MPH (on motor launch) and only use up to Hitec HS-81 for aileron and flaps (4 servo wing). My RES planes use HS81 but I am moving to HS65 in my next altitude limited electric soaring (ALES) glider.
I have an Airtronics Legend 113" (fastest that I have because it has very high wing loading) that uses all HS81 (metal gear on flaps).
I have generally moved to the Metal Gear for flaps as well as rudder (due to spins on landing which can wipe out the gear train).
For spoilers I use HK tower pro 9gr ($3) servos which have not failed ever. On some it is one installed the fuse pulling strings to spoilers, on others I just put one in each spoiler bay to directly push the spoiler.
Scott
PS - a 5-6lb 110" wing glider is pretty high wing loading.
I have an Airtronics Legend 113" (fastest that I have because it has very high wing loading) that uses all HS81 (metal gear on flaps).
I have generally moved to the Metal Gear for flaps as well as rudder (due to spins on landing which can wipe out the gear train).
For spoilers I use HK tower pro 9gr ($3) servos which have not failed ever. On some it is one installed the fuse pulling strings to spoilers, on others I just put one in each spoiler bay to directly push the spoiler.
Scott
PS - a 5-6lb 110" wing glider is pretty high wing loading.
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RE: Glider Servos
I was talking about the Skybench Big Bird XL. It has a 110" wing span. A member of the club I used to belonged to, had one and it was amazing. I did not think to ask about his set up at the time. Thank you for trying to help.
http://skybench.com/index.html?http:....com/home.html
http://skybench.com/index.html?http:....com/home.html
#6
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RE: Glider Servos
For the usual wing mounted servos for ailerons and flaps I like to use the biggest and strongest that will fit in the thicker portion of the wing just behind the main spar. That way I'm sure that even with higher speeds the torque will not be an issue. This isn't as critical with the ailerons since those surfaces do not move far. So there's a leverage gain in the relationship between the output arm and the control horn. But for flaps it can be important since you want the flaps to move through more or less a 90 degree range. And on larger surfaces that can require some added torque ability.
In the fuselage for the rudder and elevator pretty much any standard size will do just fine.
Those 225 servos certainly have more torque than needed for either the ailerons or even flaps if you had them. If your next model uses flaps the metal geared 225MG would be a wise choice simply due to the frequency of dragging flaps during landings if not careful. I suspect that most glider guiders are like me and for a regular belly slide landing tend to retract the flaps when the model is passing down through that last foot of air before touchdown simply to avoid the high back load on the flap servos.
In the fuselage for the rudder and elevator pretty much any standard size will do just fine.
Those 225 servos certainly have more torque than needed for either the ailerons or even flaps if you had them. If your next model uses flaps the metal geared 225MG would be a wise choice simply due to the frequency of dragging flaps during landings if not careful. I suspect that most glider guiders are like me and for a regular belly slide landing tend to retract the flaps when the model is passing down through that last foot of air before touchdown simply to avoid the high back load on the flap servos.
#7
RE: Glider Servos
Hitch 225 MG 's the key to trouble free is MG , hey, it even rhymes . But seriously , hitch servos have served me reliably for years . For just a few bucks more per servo , the metal gear option is the way to go .
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RE: Glider Servos
Hitec improved on the 81 series with the 82 series. I have the Big bird XL, your gonna love it! Ray is helpful but sometimes comes accross the wrong way. He is great at kit building but has gotten a bit tired of answering the same questions over and over. (admitedly time consuming) Most people overlook this cuz his products are superb. ALL the info needed for his kit are easy to find. Also look on RCGroups.com
I would use this servo hitec 82mg
http://www.hitecrcd.com/products/ser...i/hs-82mg.html
for rudder and elevator and any small 9gm servo for the spoilers.
Be sure and look up all the build logs on the bbxl and OLY III cuz they are very similar in the building.
The BBXL is not a beginner's kit, however it is not a hard build either.
get a roll of blue masking tape and label EVERY piece in the kit. tripple check! then follw the directions CAREFULLY. The result is a wonderful glider. It requires more than a standard high start. I use a hose monster 3m rig or winch. It is a great model to electrify as well. ENJOY
I would use this servo hitec 82mg
http://www.hitecrcd.com/products/ser...i/hs-82mg.html
for rudder and elevator and any small 9gm servo for the spoilers.
Be sure and look up all the build logs on the bbxl and OLY III cuz they are very similar in the building.
The BBXL is not a beginner's kit, however it is not a hard build either.
get a roll of blue masking tape and label EVERY piece in the kit. tripple check! then follw the directions CAREFULLY. The result is a wonderful glider. It requires more than a standard high start. I use a hose monster 3m rig or winch. It is a great model to electrify as well. ENJOY
#9
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RE: Glider Servos
OzMo
I had planed to build it Electric. I would have no help with a high start or really anything else. I didn't mention it before, in case it would offend the purist. Thank you for all the info.
Jim
I had planed to build it Electric. I would have no help with a high start or really anything else. I didn't mention it before, in case it would offend the purist. Thank you for all the info.
Jim
#11
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RE: Glider Servos
The Skybird is not a glider you fly fast so your torque needs will be very small. Hitec HS-85s will have way more torque than you would need. I would put HS-85s in the fuse and 85s orin the wings. I only feel the need formetal gears on flaps. So I would use nylon gears for your implementation.
I have gone digital on most of my gliders. Hitec has the 5085s which are metal gears. That is what Ihave for my Bird of Time.
I have gone digital on most of my gliders. Hitec has the 5085s which are metal gears. That is what Ihave for my Bird of Time.