Servo Choice

Reply

Old 05-25-2017, 04:40 AM
  #1  
RickP
Thread Starter
My Feedback: (2)
 
RickP's Avatar
 
Join Date: Jan 2002
Location: Levittown, NY
Posts: 1,937
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Servo Choice

Hello all,
I know that for a .60 sized pattern ship I can pretty much use any standard sized servo, but I have to imagine that there are some really nice Digital fast acting servos out there these days which are pretty economical. What do you guys like to use?
RickP
RickP is offline  
Reply With Quote
Old 06-01-2017, 04:45 PM
  #2  
grotto2
My Feedback: (2)
 
grotto2's Avatar
 
Join Date: Feb 2003
Location: Palm Bay, FL
Posts: 1,035
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Futaba S3152.
grotto2 is offline  
Reply With Quote
Old 06-01-2017, 06:23 PM
  #3  
HighPlains
My Feedback: (1)
 
Join Date: Mar 2003
Location: Over da rainbow, KS
Posts: 5,085
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Oh my, I just about died. "Don't want unlucky people on my team" tag line is the best ever!
HighPlains is offline  
Reply With Quote
Old 09-18-2017, 07:05 AM
  #4  
Mr-Punk
My Feedback: (2)
 
Mr-Punk's Avatar
 
Join Date: Sep 2011
Location: Knoxville, TN
Posts: 80
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

They are not digital but Hitec HS-485HB is what I use in 60 size SPA planes. At 18 bucks a piece it's not a big investment. I like the Karbonite gears they are stronger than nylon without the slop of metal gears.

Pretty strong at 83oz/in with 6v
Mr-Punk is offline  
Reply With Quote
Old 09-20-2017, 11:09 AM
  #5  
Psychron
Member
 
Join Date: Sep 2017
Location: Warren, MI
Posts: 62
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default How big do they really need to be?

So hey guys, I want to run this past you all. I run 9 gram servos in all my foam builds. I've run 4 gram servos just as a way to conserve weight in smaller craft.

The question I have is, Is it really necessary to run a servos larger than 9 grams for a control surface like an aileron or elevator or even throttle on a gasser when those surfaces will never have any appreciable pressure on them? Like is there any evidence to support a 9 gram servo on a .60 powered aircraft being incapable of successfully running the elevator or ailerons? I understand larger might be necessary for rudder/nose gear combos.. or rudder attached wheels on larger planes because you're dealing with gravity and surface contact at that point.

I'm just not sure they're absolutely required. At 60 miles an hour I have a feeling a 9 gram servo has more than enough power to move and hold an 8 square inch control surface in place, because there's just not that much stress on those control surfaces, especially since my mighty mini flying wing with an elevon setup does about 50, and the control surfaces are maybe 15 square inches of surface area each.


BTW, all my 9 gram servos are either EMAX or the kind you get off amazon at $2.00 a piece. They haven't failed me yet.. I have a fishing tackle box filled with all these small parts. Looking forward to my next build.

Last edited by Psychron; 09-20-2017 at 11:14 AM.
Psychron is offline  
Reply With Quote
Old 09-20-2017, 01:35 PM
  #6  
flywilly
My Feedback: (121)
 
Join Date: Feb 2002
Location: glen allen, VA,
Posts: 2,024
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Hi Dan,
Back in the day (early '80s), the torque rating on my Futaba S131 servos was 42oz/inches at 4.8 volts (the only option) and those worked fine in 60 powered pattern ships. Increased torque and speed along with ball bearing supported output shafts provides better resolution. I fly mostly high end digital servos, but still some good quality analog servos in my sport airplanes. I flew an old MK Wild-7 which had old (like 25 years old) but top quality at the time servos (Futaba). The airplane flew fine, but I felt like I was flying in mud because the response was noticeably slower that my other airplanes. Lastly, I have never run 'cheap' servos; so I can't really address their performance or durability. I have servos that continue to perform well after 1,000 flights in a glow powered pattern ship. The engine is soft mounted which is certainly a contributing factor.
My 2 cents worth... :-)
-Will
flywilly is online now  
Reply With Quote
Old 09-22-2017, 05:48 AM
  #7  
Psychron
Member
 
Join Date: Sep 2017
Location: Warren, MI
Posts: 62
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by flywilly View Post
Hi Dan,
Back in the day (early '80s), the torque rating on my Futaba S131 servos was 42oz/inches at 4.8 volts (the only option) and those worked fine in 60 powered pattern ships. Increased torque and speed along with ball bearing supported output shafts provides better resolution. I fly mostly high end digital servos, but still some good quality analog servos in my sport airplanes. I flew an old MK Wild-7 which had old (like 25 years old) but top quality at the time servos (Futaba). The airplane flew fine, but I felt like I was flying in mud because the response was noticeably slower that my other airplanes. Lastly, I have never run 'cheap' servos; so I can't really address their performance or durability. I have servos that continue to perform well after 1,000 flights in a glow powered pattern ship. The engine is soft mounted which is certainly a contributing factor.
My 2 cents worth... :-)
-Will
Hey Willy,

Thanks for the techical information. I think my first fubaba radio for a .40 powerd craft came with those 131s. 42oz is about 2 lbs 10 oz./inch I don't know how to or if I need to convert the inches to centimeters on these little foreign servos I have but the 10 pack I bought on amazon was available in two sizes.. on was 4.5lbs /cm and the other, cheaper ones at 2 bucks a piece (what I bought) will do somewhere around 3.4lbs /cm.

As for longevity, I've been using them quite a bit in my builds and they're doing a great job so far. 3 years running on the same planes with no sluggishness or anything, so I'm pretty pleased overall with their performance. So based on the stall torque you provided, these 2 dollar servos should be more than enough.

I did this video and replaced the stock parkzone servo which was supposed to he sealed (it was not) and was supposed to not short out (it did) and so instead of being stupid and buying a new parkzone servo to stick in the same stupid place where the water pools up when water gets in the hull of the craft, I put one of the two dollar ones in and changed the mounting location, as well as go over how I waterproofed the hull (which caused the failure) with white gorilla glue. Excuse my 10 year old son and his shameless plugs. I tried to let him be my camera man.. well... you'll see how that turned out. I'm just trying to get him interested in RC flight, and I figured having him help me make movies would be the best way to get him started and interested.

When we get to the inside view of the plane you can see the brand I'm talking about: I'm hoping the little bit of play in the rudder doesn't affect the as3x or I'm going to need to pull it out and put in a more rigid block of foam, but the play is about 1mm so..

Psychron is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service