Location: UNITED STATES
HobbyKing RC Model HomePage RC Radio Control Help and Support RC Hobby Forum Contact our RC Hobby Support Staff About HobbyKing
RC Model Planes RC Model Cars RC Model Helicopters RC MultiRotor and Quadcopters RC Boats RC Electronics
AIRPLANES AIRPLANE ACCESSORIES POWER SYSTEMS RADIO SYSTEMS
TELEMETRY & FPV
 
 
 
 
 
CARS CAR ACCESSORIES POWER SYSTEMS RADIOS
 
 
BOATS BOAT ACCESSORIES POWER SYSTEMS RADIOS
HELICOPTERS HELI ACCESSORIES POWER SYSTEMS RADIOS
 
 
 
MULTIROTORS ACCESSORIES POWER SYSTEMS RADIOS
ELECTRONICS ELEC. ACCESSORIES
EMAIL  PASS 
TOTAL $0.00 QTY 0
Planes & Parts
Helicopters & Parts
Multi-Rotors & Parts
Cars & Parts
Boats & Parts
Bikes & Parts
Scale R/C Tanks
FPV & Telemetry
Batteries & Accessories
Chargers & Accessories
Electric Motors
Speed Controllers
Robotics & DIY
Servos & Parts
Radios & Receivers
Gas/Glow Engines & parts
UBEC & Regulator
Power Systems
Hardware & accessories.
Tools
Clothing, Gift & Acc.
Sale/Liquidation

Language
Currency
USA warehouse now open.
Our USA warehouse is now open! Low cost shipping and an ever growing variety make ordering from the US warehouse even better value!
  Item found in the following categories;
> Servos & Parts > All Servos
> Servos & Parts > Mini Servo 11-20g
> Servos & Parts > Blue Bird Servo

  RATED:

BMS-385DMAX Digital Servo (Metal Gear) 4.2kg / .15sec / 16.5g

BMS-385DMAX Digital Servo (Metal Gear) 4.2kg / .15sec / 16.5g


BMS-385DMAX Digital Servo (Metal Gear) 4.2kg / .15sec / 16.5g
This servo is designed to be used in R/C glider applications. By using carbon nylon gears and optimizing the curvature of the gears, the gears are able to withstand large amounts of force.
The servo will automatically learn the users transmitter pulse timings and lock into the signal every time. The servo also includes a signal buffer in the CPU with fail-safe functionality.
The servo comes with an accessory package and the universal JR/Hitec "S" Connector which is physically and electrically compatible with all major receiver brands sold worldwide.
 
1. M9.6 ball bearing (si-oil)
2. Extra Strong torque with low signal affect and success get CE certification.
3. Rubber seals for waterproof case
4. Designed to be used in R/C glider applications.
5. Futaba compatible 25-tooth aluminum 6061 output splines
6. Digital motor drive with ultra-square PWM signal
7. Automatic determination of servo center pulse width
8. Metal gears of aluminum 6061 material combined with light and strong C95 material
9. Fail-Safe function
10. Digital control IC - SOP package with 12bit data transfer
11. MOS-FET motor driver chips that can handle 7A peak loads
12. Useable on 6.0V
 
   
Weight: 16.5grams / 0.59oz
Dimensions: 26 x 13 x 26 mm / 1.16 x 0.51 x 1.02 inch
Torque At 4.8V: 4.2kg/cm , 57 oz/in
Torque At 6.0V: 4.7kg/cm , 62 oz/in
Speed At 4.8V: 0.15sec / 60 deg at no load
Speed At 6.0V: 0.13sec / 60 deg at no load

PRODUCT ID: BMS-385DMAX

Weight (g) 16.5
Torque (kg) 4.7
Speed (Sec/60deg) 0.13
A(mm) 37
B(mm) 27
C(mm) 31.5
D(mm) 13
E(mm) 36
F(mm) 20
Update/Add my own data
Customer Data
38g Back warehouse: 0 -12 $20.48
Email Buddy Issue Price War
acc.
  • Futaba/JR Connector caps (5pcs/set)

    Combo Price: $0.94   BACKORDER



Further discounts available for registered & logged-in customers.
STOCK ARRIVAL ALERT

Enter your email address to get an email the second new stock arrives.
Estimated factory delivery date;
 Customer rated
481
crowns
  
 
Total of 17 discussions.
Trackercj  23 points - 5/12/2013
 
I have been waiting for over 2 months now, i guess its not going to be in stock anymore?
 Charles 75 points
They said it should come in 2-3 week
 MrMat 2 points
They always say that.
Charles  75 points - 5/10/2013
 
This is getting really annoying, like I've been waiting for almost 2 month and there's still no estimated delivery date. This is just really getting annoying
 Victor 9 points
Have you sign up for E-mail stock alert? Because a motor i wanted to buy came in stock and sold out on less than an hour :(
 Charles 75 points
i already bought it im just waiting for it to come back in stock
Tallineau  4 points - 5/7/2013
 
Restock, restock please!!!!!!!
Peter  3 points - 5/1/2013
 
Can someone list some other decent servos for a tri-copter build... As I am tired of waiting for this one to be in stock?
 Strange_1 8 points
I'm going to use the HS-82MG. Its analog, but its a very high quality metal gear Hitec servo. Check out this guys video, he's using one on a tri with a KK2.0 and a very simple yaw mechanism.
 7sp7sp 40 points
The BMS-390DMH looks pretty good. We are using them a couple of RCexplorer v2.5 builds. A little more torque, few grams heaver and a little faster. ...Except after I started typing this I checked and they are now back ordered as well. Must have placed just in time.
 Strange_1 8 points
The Turnigy TGY-210DMH also looks like a strong contender. Specs at 3.9kg/.13sec/16g, Metal gear Coreless Digital Servo w/ Heat Sink. I've got one on order.
Trackercj  23 points - 4/19/2013
 
Restock please!
guroos  2 points - 1/12/2013
 
I would like to know frequency as well, thanks.
Scott  6 points - 1/10/2013
 
What is the max update frequency for this servo? (in Hz)
Big Mr.  24 points - 1/4/2013
 
Using this servo on the V2.5 Tri is not recommended. the adverse yaw motion and force needed to correct and steer the tri Is a little too much when using the DT700 Motor. A larger servo is recommended. I am using a 1:10 scale steering servo. the DT700 is more than enough to carry the extra weight and Piece of mind. This servo Is very strong and well built but be sure to purchase a replacement gear set when ordering.
 Roger 2701 points
Are you referring to rcexplorer tri? I build this tri too with this servo from david's list and it works well.
 Big Mr. 24 points
Yes same one. I had a blade strike and a gear stripped. I just expected more rigidity. As before make sure to order a replacement gear set so you aren't downed while waiting for a replacement. Cheers!
 argus0209 27 points
I build the 2.5 and have had a ton of crashes and mine still looks new. I would recommend it.
lpbug  20 points - 11/26/2012
 
are there replacement arms available for this servo? If so, what are the size?
 Big Mr. 24 points
a link to the replacement gear set on this page would be appreciated
Dave  3 points - 11/18/2012
 
Is this servo compatable with the Corona 6 chanel RX?
( BMS-385DMAX )
Thanks Dave
RoboHead  2 points - 10/22/2012
 
Good day, I have used one of these in a Tricopter build, but only after a few flights seems to have burnt out its Amplifier/Control board. Is it possible to replace these boards? Appreciate the help!
 Jonas 9 points
Hi
If the control board burned out, it's usually two things to consider.
1st Ensure that your application is easy to operate! Is it heavy, it is usually the reason it burns up.
2nd If it is easy, but still burns the servo is too weak. Change to a stronger!

Then there is the issue of brand! In this case, BMS, I have last year purchase several pieces of it. They have simple tasks, such as driving a throttle. But basically all the servos of this model has overheated and burned up. BMS seems t
Krimbu  17 points - 9/15/2012
 
Hi folks, I've ordered this servo as it was on the shopping list of the tricopter v2.5 that i want to build. But this servo is back ordered since long time. Is there any other you would recommend instead? Thanks
 mena142 746 points
For my tricopter v2 build I used a Turnigy metal gear servo, which worked great with the previous yaw mount. I eventually lost it to rain (whihc the BMS is water tight). I honestly don't see anything as good as the BMS for the price, but I'd search for "metal gear digital servo" and try and find something with similar specs. I've seen a couple of people using the TGY-375DMG for this kind of direct drive yaw mechanisms and they work great.
BEST ANSWER CREDIT AWARDED
Jean  5 points - 5/1/2012
 
that's a good servos for helicopter?
 Vionnet 1051 points
yes of course, good quality good price buy it !
BEST ANSWER CREDIT AWARDED
mole0815  6 points - 2/5/2012
 
Hi, i need some spare servo arms (cross) for this servo, are there some compatible ones here on HK? i was looking for some at several hobbystores in my area and non had compatible ones... :/ i was wondering if theese: product id: MI-SERV-HORN will work? any ideas? thanks in advance! cheers!
 Samuel 6 points
Servos basically come in 3 different sizes (micro, standard, and giant or 1/4 scale). This servo is a standard size, so almost any sevro arm made for a non-micro or non-giant size servo will work. I'm pretty sure "HobbyKing Mi Servos" means micro, but I'm not completely sure. If you have any spare arms, anything will fit this servo that is not micro or giant. Otherwise you may have to shop somewhere elsewhere. hobbyparts has a bunch of cheap servo arm sets that will work for you.
BEST ANSWER CREDIT AWARDED
 mole0815 6 points
ahh ok, thanks!.. well i found some servo arms at home, that have the same diameter and also would fit, BUT the teeth inside do not fit... i also went to a hobbyshop and asked them for arms for this specific servo, we tried some there, but same problem, size was ok, but the teeth inside did not fit.. so are there some "standards", concerning the "teeth" of servo arms? or has every company its own standard? cheers!
 Samuel 6 points
There's at least 4 common servo spines, 21-25 teeth you're bound to run into, since it's hard to count the teeth manually it's pretty much trial and error. ***mer that your hobby shop doesn't stock 25 tooth - say Futaba brand servo horns (which is exactly what you need), sorry it was so much trouble for you. Hope you find exactly what you need here: *******servocity****/html/futaba_arms_horns.html , these should be 100% compatible with a standard size 25 tooth servo like the BMS-385DMAX.
 mole0815 6 points
hey, thanks again!
MarcusRjCharita  425 points - 3/28/2010
 
Hi folks, I am not an expert in this hobby nor in electronics and I need a help. I got three of these and two of them make a "flying beatle" noise at centered position and without any Tx input. It is not a high volume noise but I never experienced this before. I bought several servos (usualy turnigy and original futaba), both analogic and digital and they are absolutely quiet with Tx stick at neutral position. I think these noisy ones are NOT OK. I am not confident about them. Does someone can tell me why the servo is "buzzing"? Servo does not move with Tx sticks at neutral position, but is behave like it is getting signal from Tx. Can I fix it by myself or should I return them to HK? Many thanks.
 glbiggles 54 points
Don't worry too much about it. Digital servos commonly hum at centre, particularly if there is a little load on hinge (line not straight)or tight linkage. The noise is amplified by the covering on model. The buzz is the servo trying to get to neutral.
 MarcusRjCharita 425 points
****
 glbiggles 54 points
Marcus you are right they hum at centre. However as i said this is common with digitals. caused by the low deadband at centre. It is not as obvious when servo is not mounted in model. I have found that it is not a problem. I have a lot of models with various brands of digital servos and they all have this noise to some extent.
BEST ANSWER CREDIT AWARDED
 MarcusRjCharita 425 points
****
 nonweru 29 points
with digital servos, it's normal to have this kind of noise. don't worry.
 bwoollia 320 points
I measured the current on these servos when they were buzzing and when they were not - a very slight increase but not enough to cause any concern.
 bwoollia 320 points
I measured the current on these servos when they were buzzing and when they were not - a very slight increase but not enough to cause any concern.
modelkin  19 points - 8/13/2009
 
max A/h ???
 Cyberdactyl 12 points
HOBBYKING needs to put a flag on across the main graphic for this part, and that is it stays on backorder for LONG periods. I understand HK offers the email function, however that gives no indicator you could be waiting for several weeks.
Bohumil  136 points - 6/2/2009
 
Koupil jsem dvì na zkoušku do modelu F3X na klapky.zatím jsou výborné a fungují jak mají!Rozpìtí modelu je 3000mm a váha 3200g.
info:
****boban.websnadno.cz
sekce f3x modely
Boban
Customer Reviews
Create an account
Overall Rating
MarcusRjCharita
331 likes
ValueUNRATED
QualityUNRATED
74 thumbs up!
Bought three of these and two of them make a "flying beatle" noise at centered position and without any Tx input. It is not a high volume noise but I never experienced this before. I bought lots of servos, both analogic and digital and surely these ones (66pcnt !) are NOT OK. I am not confident about them and I will not risk a plane with these servos.


2 comments. Reply..

Overall Rating
kurtus420
111 likes
ValueUNRATED
QualityUNRATED
44 thumbs up!
I bought 1 and it showed up DOA, the gears were completly jammed in it. Sent it back 40 days ago and haven't received anykind of response from hobby king yet. Giving it 3 stars for the fit and finish but I never got to test it so I can't do a 5 star rating.


No comments. Reply..

Overall Rating
Karl
28 likes
ValueUNRATED
QualityUNRATED
17 thumbs up!
The auto-centering of these servos is terrible. They cannot find the Center and so they hunt and make a high pitch buzzing noise. I do not trust these in my glider and so will throw them in the bin. Waste of time and money if you buy these servos.


No comments. Reply..

Overall Rating
malcomx
101 likes
ValueUNRATED
QualityUNRATED
16 thumbs up!
I bought 2 of those, 1 was burned during third flight, plane was almost crashed, second one I put to the trash for prevention. Don't recomend to buy.


2 comments. Reply..

Overall Rating
guillaumeM
24 likes
ValueUNRATED
QualityUNRATED
16 thumbs up!
J'ai command 4 servos et il crame les un aprs les autres je vais les changer avant le premier vol! Je pensais mettre un peu plus cher et en avoir des meilleurs et c'est faux!:( Premire fois que je suis du du matos de HK

I ordered 4 servos and it burns one after the others I am going to change them before the first flight! I thought spend more money for having best quality and it's wrong!:(First time when I am disappointed by HK product


No comments. Reply..

.....click here to see all reviews
 
Aff. Link

Copyright 2012 Hextronik Limited.
The HobbyKing.com®, OrangeRx, Turnigy, Durafly, nano-tech and other brand logos and names are trademarks of hexTronik Limited.
All rights reserved