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-   -   "JR type" servos for UCD3D (https://www.rcuniverse.com/forum/3d-flying-82/738946-jr-type-servos-ucd3d.html)

beerman 05-02-2003 11:50 AM

"JR type" servos for UCD3D
 
Not sure this is the right place to ask this, but need some suggestions on which servos to put into the UCD3D. I'm looking for something middle of the road and reliable. Running a JR8103. Thanks!

Doug Cronkhite 05-02-2003 12:37 PM

"JR type" servos for UCD3D
 
Try the new JR DS811 Sport Digitals. Dick Hanson has been running them in much larger stuff than a UCD3D with GREAT results. It has 66oz" of torque on 6v, and you can find them for under $50 each.

If you give me the recommended servos from the UCD3D manual, I can make a better suggestion.

Doug Cronkhite
Team JR

beerman 05-02-2003 12:46 PM

"JR type" servos for UCD3D
 
Thanks for the reply. It recommends Futaba of course, but the following is what it says. Looks like your suggestions are spot on, and the price is very nice as well. Rudder might need something a bit beefier.

Ailerons - 2 BB 50+ in oz

Rudder - High Torque 90+ in oz

Elevator - 2 BB 50+ in oz


Thanks again!
Jason

Doug Cronkhite 05-02-2003 12:53 PM

"JR type" servos for UCD3D
 
For the rudder, I'd go with the 8231, 8411, or 8411SA (if you prefer nylon gears).

-Doug

beerman 05-02-2003 12:57 PM

"JR type" servos for UCD3D
 
Great info, thanks!

Texas 3D 05-02-2003 01:44 PM

"JR type" servos for UCD3D
 
You do not need to run digital servos in this 60-90 size plane.
If I would build it (that's what I have in my Showflyer), I would put in it :
JR 4131 on ailerons and elevator, and a 2721 (faster) or 4721 on rudder.
This is enough servo for it. Another way to save some servo money is going with Hitecs. 625MG's instead of JR 4131's and a 645MG instead of JR 2721 or 4721 ! Any standard size servo for the throttle will work fine. I use JR 537's.
Make sure you keep everything light and use a light receiver (JR Slimline 700 or Hitec 555), and a light 6V battery pack. The 6V gives you top servo speed and performance. The 6V 1650 NIMH pack from Batteries America or RadicalRC use AA size Batteries. Batteries America now have a 2000 pack with AA size batteries.
Light weight and therefore low wing loading is the key to optimal performance of these 3D machines.
Just my $0.02

beerman 05-02-2003 02:09 PM

"JR type" servos for UCD3D
 
I like the way you think...I was adding things up and it was dang near the same price to buy a new 8103 digital package. Thanks for the input!

Doug Cronkhite 05-02-2003 02:58 PM

"JR type" servos for UCD3D
 
I would disagree. The servos are your direct connection to the airplane. You want them as precise as possible. Saving money on servos results in a sloppier flying airplane overall.

Also.. the DS 811 is only $47.95 at most places whereas the 4131 is $79.95.. so you're saving money by running the DS 811 DIGITAL.

-Doug

Texas 3D 05-02-2003 05:15 PM

"JR type" servos for UCD3D
 

Originally posted by dcronkhite
I would disagree. The servos are your direct connection to the airplane. You want them as precise as possible. Saving money on servos results in a sloppier flying airplane overall.

Who says the Hitec servos are bad servos and will result in a sloppier flying ? I think the Hitec are well proved servos and should be enough for this airplane. I have used these particular servos a lot, and have had great results with them. The DS811 is fine, but you do not need a DS8411 or DS8231 on this plane.
If we would be talking about a bigger plane (33%-40%) you would be absolutely correct, and I would also buy Digital servos.

m.gramling 05-02-2003 06:15 PM

"JR type" servos for UCD3D
 
I fly my UCD with standard JR BB 517's on everything except rudder. On rudder I have a Hitech 605. which has 77oz of torgue on 4.8volts.

I am running a 90 2 stroke on a moosecan muffler, and I can do knife edge loops, Snaps, and blenders are no problem.

Put a good servo on the rudder, and run standard BB's on everthing else. I believe in good servos for the job, however in my opinoin this plane doesn't need expensive servos.

Flyfalcons 05-02-2003 06:34 PM

"JR type" servos for UCD3D
 
m.grambling has it. I have standard precision 3001 Futabas on everything except the rudder, which got a 90oz 4735. I can do pinwheels with this combo. There is absolutely no reason to go with digitals on this 90 size fun fly plane. You can see a few short vids of mine at my website.

Iflyrc4fun 05-02-2003 06:47 PM

"JR type" servos for UCD3D
 
New JR DS 811 servos sell everyday on Ebay for $35.00 and occasionally you can get a bid one for closer to 30.00. If you purchase several the shipping is quite reasonable.

Doug Cronkhite 05-02-2003 09:26 PM

"JR type" servos for UCD3D
 
Maybe it's just because I've been a precision aerobatic/IMAC guy for so long.. but servos are a place I never try to save money.. The reason I suggested an 8231 or 8411 was for the rudder only, which GP recommends at least 90oz of torque.

-Doug

m.gramling 05-02-2003 11:33 PM

"JR type" servos for UCD3D
 
drcronkhite,
I agree with you on expensive quality servos on certain planes they are definately needed. But to me, on this plane except for the rudder their not needed. I absolutely flop and flip the snot out of this plane with standard servos. To me this is not a precision flying type of aircraft, its a knock around plane.

I might eat my words later on the standard servos but I have been flying the snot of it for a few months, and have been fine.

OnTheEdge 05-03-2003 12:48 AM

Best of both worlds.........
 
Try the new Hitec "econo" digitals HS-5475. I got mine for about $34 from my LHS. I have them on the ailerons and elevators of my UCD and they work great. I had some 615's on there last season but they are very sloppy around neutral (they had a lot of flights on them with another plane though).

I have a 5625 on the rudder (overkill on torque but priced well for this type of plane) ($54)

FWIW....I also run 6v rx pack.


http://www.servocity.com/ServoCity/P...b_digital.html

beerman 05-04-2003 12:10 AM

"JR type" servos for UCD3D
 
I'm not one who skimps on things to get by, but I don't want to put in something that's absurd overkill either. I'm failry new to the hobby so I'm not familiar with the types of sero failures, other than a stripped servo on my US40 after a hard tail first landing(crash). By going with a non digital, or super high torque model, other than stripped gears in an accident, what could fail??? Will they not pull the surface all the way? Will they strip in the air? Thanks for all the replies, it is somewhat entertaining. :)

brittain 05-05-2003 01:34 AM

"JR type" servos for UCD3D
 
I'm using JR 8411SA on the rudder and 8231s on the aileron and elevators. I'm using a LiO pack with a 5.6 vdc regulator. I put these servos and battery in as I wanted to check them out before I put them in my new pattern plane. Originally I had Futaba 9001s on the elev & ailerons. What a difference the new servos and extra volts made. The plane is far more precise and a whole lot easier to hover. You can't beat power and accuracy!! I can also now do a wall with low rates as defined in the manual! The servos are that much faster.

Dansy 05-06-2003 07:51 PM

"JR type" servos for UCD3D
 
I'm using 5 DS8411SA and a micro on throttle, work's for me I might even use these servo's if I ever buy a Funtana or similar design in the future (soon I hope :) )

beerman 05-06-2003 07:59 PM

"JR type" servos for UCD3D
 
I would guess you have zero issues regarding torque for this plane!!! :)

beerman 05-07-2003 02:27 AM

"JR type" servos for UCD3D
 
Thanks all for the advice on what to get...I went with Hi-Tech HS-605BBs for everything but the rudder where I put a Hi-Tech HS-945MG. I'm guessing these should do well for the UCD3D.


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