SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Feb 27, 2012, 12:48 AM
Registered User
United States, CA, Signal Hill
Joined Aug 2009
865 Posts
Discussion
anyone tried these corona 929 mg servos ?

there much faster then my old servos the copter feels super responsive now i think i may need to lower the elevator and aileron swash afr .

what do you guys think should i lower the limits aka end points to make it less responsive

corona digital 929 mg servo test in the titan trex 450 RC Helicopter. (7 min 3 sec)


here are the specs 27 bucks for 3

Fully compatible GY401 Gyro (Not include Gyro)
Metal gear Better impact
Has a high response rate and back-precision
400-500 level suitable for the use of electric helicopter.

Higher resolution
The tightest dead band
Accurate positioning
Faster control response
Quicker acceleration
Constant torque throughout the servos travel
Increased holding power when stationary

Specification:
Operating voltage range 4.8V ~ 6.0V
Operating temperature range -20'c to +60'c
Operating speed 0.12sec/60' degree
Stall torque 2.5kg.cm / 36.10 oz. in
Standing torque 24.99 / 30.55 oz. in (4.8v/6v)
Running current 200mA/60? no load
FDead band width ?3mS
Operating travel 40' /one side pulse traveling 400S
Motor type cored metal brush
Potentiometer type 2 slider/direct drive
Dimensions 22.5x11.5x24.6mm (0.89 x 0.45 x 0.97)"
Weight 12.5g
Ball bearing MR85
Gear material metal
Connector wire length 215mm(8.46in)
Connector wire stand counter 24
Connector wire gauge 28AWG
wc_wickedclown is offline Find More Posts by wc_wickedclown
Reply With Quote
Sign up now
to remove ads between posts
Old Mar 17, 2012, 01:52 AM
Registered User
United States, CA, Signal Hill
Joined Aug 2009
865 Posts
new mg servos horns
titan trex 450 with corona 929 digital mg servos with cnc servo arms maiden 55th hover (4 min 58 sec)
wc_wickedclown is offline Find More Posts by wc_wickedclown
Reply With Quote
Old Mar 17, 2012, 03:44 PM
just gotta mess with it!
2Doggs's Avatar
North West Louisiana
Joined Nov 2009
4,653 Posts
Backlash!

I just bought some as a cheap alternative to Henge MD933MG and MD922MG servos. The Henge servos are also on backorder right now.

I fitted them to a 450 Pro, but haven't flown it yet. I like the servo cases - they seem quite a bit more durable than the Henge, especially around the mounting lugs.

The gears have quite a bit of backlash though - more than the MD922's, and much more than the MD933's. The worst one of the four I bought has maybe approaching 1mm of movement at the end of the servo arm, and the others maybe just over 0.5mm.

On my CX program box servo tester, the Coronas show about 0.12s at 5.3v - so pretty much in line with their claimed speed. By contrast, the Henge servos show about 0.13s, significantly slower than their claimed spec.

So for the money, they might turn out to be a pretty good buy - but it's a pity about the backlash.
2Doggs is offline Find More Posts by 2Doggs
RCG Plus Member
Latest blog entry: Nano Tech 1800mah 4S 25-50c
Reply With Quote
Old Mar 17, 2012, 03:49 PM
Registered User
United States, CA, Signal Hill
Joined Aug 2009
865 Posts
Quote:
Originally Posted by 2Doggs View Post
I just bought some as a cheap alternative to Henge MD933MG and MD922MG servos. The Henge servos are also on backorder right now.

I fitted them to a 450 Pro, but haven't flown it yet. I like the servo cases - they seem quite a bit more durable than the Henge, especially around the mounting lugs.

The gears have quite a bit of backlash though - more than the MD922's, and much more than the MD933's. The worst one of the four I bought has maybe approaching 1mm of movement at the end of the servo arm, and the others maybe just over 0.5mm.

On my CX program box servo tester, the Coronas show about 0.12s at 5.3v - so pretty much in line with their claimed speed. By contrast, the Henge servos show about 0.13s, significantly slower than their claimed spec.

So for the money, they might turn out to be a pretty good buy - but it's a pity about the backlash.
i never paid attention to check for any backlash i just checked them and one has a minor bit of it .

but for the price with them cnc servo horns my beater heli is a happy bird.

thanks for the heads up
wc_wickedclown is offline Find More Posts by wc_wickedclown
Reply With Quote
Old Mar 17, 2012, 05:15 PM
just gotta mess with it!
2Doggs's Avatar
North West Louisiana
Joined Nov 2009
4,653 Posts
Quote:
Originally Posted by wc_wickedclown View Post
i never paid attention to check for any backlash i just checked them and one has a minor bit of it .

but for the price with them cnc servo horns my beater heli is a happy bird.

thanks for the heads up
Those CNC arms look solid! I daresay the servo gears will strip before the arms break in a crash!

Did you trim the one on the left side down - they look long enough to reach the maingear, and you wouldn't want that!
2Doggs is offline Find More Posts by 2Doggs
RCG Plus Member
Latest blog entry: Nano Tech 1800mah 4S 25-50c
Reply With Quote
Old Mar 17, 2012, 08:20 PM
Registered User
United States, CA, Signal Hill
Joined Aug 2009
865 Posts
Quote:
Originally Posted by 2Doggs View Post
Those CNC arms look solid! I daresay the servo gears will strip before the arms break in a crash!

Did you trim the one on the left side down - they look long enough to reach the maingear, and you wouldn't want that!
yes i checked the trim thanks for asking and for 9 bucks if one gets stripped ill buy 2 more i should have bought extras
wc_wickedclown is offline Find More Posts by wc_wickedclown
Reply With Quote
Old Mar 18, 2012, 08:35 AM
Registered User
United States, SC, Irmo
Joined Sep 2011
4,604 Posts
I bought these for the tails, going to use hxt900 on the swash. would rather break a servo than something else on the bird as cheap as 900's are, and I have spare gears for those as well!
shahram72 is offline Find More Posts by shahram72
Reply With Quote
Old Mar 23, 2012, 02:54 AM
Registered User
United States, CA, Signal Hill
Joined Aug 2009
865 Posts
im digging these 929's now and i got my mg servo horns installed

=wc= titan trex 450 rc helicopter maintenance tips to get 60+ hoovers from your helicopter (8 min 53 sec)
wc_wickedclown is offline Find More Posts by wc_wickedclown
Reply With Quote
Old Mar 24, 2012, 12:42 PM
Registered User
United States, CA, Signal Hill
Joined Aug 2009
865 Posts
test 2 @ 40% dual rate
titan trex 450 61st hover 40% dual rate test 929 mg servos tail in hover fun lol. (7 min 31 sec)
wc_wickedclown is offline Find More Posts by wc_wickedclown
Reply With Quote
Old Mar 25, 2012, 03:56 AM
Suspended Account
Pittsburgh PA
Joined Dec 2004
2,365 Posts
show us how they are mounted... some of the MG inexpensive servos have a ridge under the mounting tabs. this causes 2 things. servo wobble and eventually broken tabs/servo cases. if this is the case, file off the ridge and ur good to go
Cable Guy is offline Find More Posts by Cable Guy
Reply With Quote  (Disabled)
Old Mar 25, 2012, 08:36 AM
just gotta mess with it!
2Doggs's Avatar
North West Louisiana
Joined Nov 2009
4,653 Posts
Whilst the mounting lugs on the 929's look nice and chunky, they're actually hollow. They also have a little stiffening fillet, when viewed side-on, on the top side where the lug meets the case. I had to file this down on one side for the elevator servo install on my 450 Pro, to prevent the fillet bearing against the top and bottom bearing supports.
2Doggs is offline Find More Posts by 2Doggs
RCG Plus Member
Latest blog entry: Nano Tech 1800mah 4S 25-50c
Reply With Quote
Old Mar 25, 2012, 08:59 AM
Registered User
United States, SC, Irmo
Joined Sep 2011
4,604 Posts
I watched the vid. These things sound cool electric! I can't wait to get my 450 airborne someday. I want to know if I saw something right. Did you land and then switch to idle up while on the ground? That looks like a good idea. I am just beginning but I noticed on my little solo pro 100 that I was trying to come down in wind in normal mode and the motor started to spool down. It was a situation where I needed negative pitch I guess. But I thought idle up was not necessary for a beginner, but I guess it is if I am going to fly in some wind.
shahram72 is offline Find More Posts by shahram72
Reply With Quote
Old Mar 25, 2012, 10:34 AM
just gotta mess with it!
2Doggs's Avatar
North West Louisiana
Joined Nov 2009
4,653 Posts
If you're a beginner, you won't be flying in too much wind - but if need be, you can add more negative pitch in your normal pitch curve to prevent the heli "floating" in windy conditions. Or you can use one of the stunt (idle-up) modes to land, but you might then want to use D/R to make it more controllable in a hover.
2Doggs is offline Find More Posts by 2Doggs
RCG Plus Member
Latest blog entry: Nano Tech 1800mah 4S 25-50c
Reply With Quote
Old Mar 26, 2012, 05:22 PM
Registered User
United States, CA, Signal Hill
Joined Aug 2009
865 Posts
Quote:
Originally Posted by shahram72 View Post
I watched the vid. These things sound cool electric! I can't wait to get my 450 airborne someday. I want to know if I saw something right. Did you land and then switch to idle up while on the ground? That looks like a good idea. I am just beginning but I noticed on my little solo pro 100 that I was trying to come down in wind in normal mode and the motor started to spool down. It was a situation where I needed negative pitch I guess. But I thought idle up was not necessary for a beginner, but I guess it is if I am going to fly in some wind.
yes i idle up on the ground just make sure your at half stick when you switch it on.

i trimmed my 450 finally just needs a tad more to stop the heli from drifting to the left.

titan trex 450 rc 3d helicopter trim day. (6 min 8 sec)
wc_wickedclown is offline Find More Posts by wc_wickedclown
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question Anyone tried THESE servos yet? target Multi Task F3X 7 Apr 16, 2011 11:23 PM
Discussion Has anyone tried one of these FPV planes from HK yet? randall1959 FPV Aircraft 1 Mar 25, 2011 07:17 PM
Discussion Has anyone tried these fans? lowkeylaidback Foamy EDFs 5 Mar 21, 2011 04:36 PM
Question Has anyone tried these new Corona servos? Maverickk Radios 3 Mar 11, 2010 01:36 AM
Question Has anyone tried these new Corona servos? Maverickk 3D Electric Heli Flying 3 Feb 16, 2010 12:28 AM