Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[macey666]

Hi all.

I have just acquired a Spektrum DX5e Transmiter which came with the AR500 Receiver, so now have to start sorting out some servos but how does one select a servo for a particular application? There are hundreds of servos out there and I have no idea how to decide which would be suitable for which application.  I guess that some considerations might be, how fast the servo will operate, how powerful it is and the size of it? 

Does anyone have some guidance?

Regards - Macey

[tomo55]

Hi Macey ,yes it can seem daunting .

I stick to standard servos mostly  (aircraft / boats) For smaller applications I have used Hitec 81 size but tend to stay away from the micros servos as they are small my hands are big and my eyesight aint what it was,I have only ever used a High torque servo once and that was in a Rockcrawler so it was needed.
I sail launches 36 inches and I use standard servo on rudder it works fine.
To sum up standard size mostly £7 each,smaller aircraft hitec 81s £9 each
Hope that helps a bit.
Chris

[andygh]

Yes, it depends what they'll be used for. I mostly use standard jobs but if I want to turn a big Kort nozzle or something I go for one with a bit more torque.
My latest boat has a couple of 2 quid servos from Hong Kong, they're fine for what I want and I haven't managed to break one ...... (yet) 

[tigertiger]

Hi Macey

What did you have in mind for the boat?

Forgive if I am teaching you how to suck eggs, but I will assume you are a novice (like we all were once).

If an electric boat you may only need one servo, for steering (any standard servo will do).
But you will also need an Electronic Speed Controller (ESC) to speed up, slow down, switch on/off the motor. Unless you want just on/off.

You can use a servo to push a mechanical microswitch, for things like lights and sounds. This would give you one function per channel.
OR
Buy a fancy electrical multi swither. These can give you up to 4 functions per channel.

You may also need other bits and bobs to protect circuits.


Like I said, give us an idea of what you want the boat to do and others, far smarter than me, can advise you better.

[macey666]

Thanks Tomo and Andy :)

Tiger - thanks for your reply - yes beginner here, but do I understand the need for an ESC
 etc and the other things you describe depending upon the type of boat and functions required..

My original question arose because I thought it a bit odd that I might be using the same servo for the rudder in my 60" electric narrowboat as in my 48" IC engined deep-V boat, as I'm sure that a bit more force and quicker response is required by the IC boat.  I already get the impression that 'standard' type servos are described as that because they are suitable for most (or many?) applications and most peoples starting point.  Am i putting too much thought into it? Use a standard servo and if it doesn't perform satisfactorily then look for something a bit more specialised?

Macey
 

[Peterm]

Go with the flow.   I use Hitec standard servos in every one of my boats, large and small(er) and have no problems.   The only time I would go smaller, is if space is at a premium.   Pete M

[FullLeatherJacket]

If I were you I'd seek out some expert advice on the right sort of servo for your IC boat; there's a Powerboats board on this forum which will certainly have some of the OMRA boys watching it. You will probably need something that's both powerful and fast; this equates to "expensive", but it's all relative.
As regards the narrow boat then, unless the rudder is like an unbalanced barn-door, you'll get away with a cheap and cheerful Brand X standard servo. I would suggest buying from a UK supplier rather than one abroad - I use Servo Shop (Steve Webb Models) for a wide choice and good value.
FLJ

[macey666]

Thank you all for your help.

Macey