collective pitch load - which servo to use.

collective pitch load - which servo to use.

Post by Ross Johnso » Wed, 11 Apr 2001 22:03:00



Hi guys,

I have put a standard JR 511 servo on my collective (Kalt Baron 30). It is
rated to 3.5 Kg/cm (I think that is about 49 oz/inch), but to get the speed
I'm looking for I'd like to run a 19mm servo horn. I noticed that pushing on
the blades will quite easily move the servo when the power is off, so do I
need a higher torque servo, or will it be all right when the power is on? Or
should I get a higher speed servo, so I can use a shorter arm? I'm not made
of money, so I'm looking for the budget solution here!

Thanks,
Ross.

 
 
 

collective pitch load - which servo to use.

Post by Beavi » Wed, 11 Apr 2001 23:49:53




Quote:
>Hi guys,

>I have put a standard JR 511 servo on my collective (Kalt Baron 30). It is
>rated to 3.5 Kg/cm (I think that is about 49 oz/inch), but to get the speed
>I'm looking for I'd like to run a 19mm servo horn. I noticed that pushing on
>the blades will quite easily move the servo when the power is off, so do I
>need a higher torque servo, or will it be all right when the power is on?

It'll be OK when the power is on, but you shouldn't really be trying to
get more speed at the expanse of power on the collective servo. Using
100% ATV on your collective channel, work out the length your servo arm
needs to be in order to give full collective travel with no binding and
that's the correct length. Any other way is compromising something.

Quote:
> Or
>should I get a higher speed servo,

You could, but I don't know why you'd need to. The 511 on a Baron 30 is
PLENTY fast enough for collective.

Quote:
> so I can use a shorter arm? I'm not made
>of money, so I'm looking for the budget solution here!

There IS a budget solution in the form of servo's that go under the name
of "J/P SuperTec" They make various servos having different speeds and
power so at least one from their range should get you what you want.

Beav

You can E-Mail me at the usual place (Beavis at nachos dot demon dot co dot uk)

Or you can visit my website (Which has undergone recent surgery) Same address as
before..

www.nachos.demon.co.uk

 
 
 

collective pitch load - which servo to use.

Post by Mike » Sat, 28 Apr 2001 06:24:08


Hi Ross,

Servos will always push easier with power off, its not really an indication
of their torque..try it with power on, you will find it a lot harder!

The 511 is 'ok', but I should think on its limits if you use a long arm and
on collective to boot. JR have actually brought out a new servo, the 591,
that is similar spec to the 511, still almost as cheap, and almost twice as
powerful. Might be worth a look.


Quote:
> Hi guys,

> I have put a standard JR 511 servo on my collective (Kalt Baron 30). It is
> rated to 3.5 Kg/cm (I think that is about 49 oz/inch), but to get the
speed
> I'm looking for I'd like to run a 19mm servo horn. I noticed that pushing
on
> the blades will quite easily move the servo when the power is off, so do I
> need a higher torque servo, or will it be all right when the power is on?
Or
> should I get a higher speed servo, so I can use a shorter arm? I'm not
made
> of money, so I'm looking for the budget solution here!

> Thanks,
> Ross.

 
 
 

collective pitch load - which servo to use.

Post by Davi » Mon, 30 Apr 2001 06:56:55


I have a 591 servo on a rappy........Crashed it the other day.  She just
wouldnt stop falling and the blade speed went up.  On investigation the
servo gears had stripped.......

I know that the crash could have stripped them, but why did it crash?

David


Quote:
> Hi Ross,

> Servos will always push easier with power off, its not really an
indication
> of their torque..try it with power on, you will find it a lot harder!

> The 511 is 'ok', but I should think on its limits if you use a long arm
and
> on collective to boot. JR have actually brought out a new servo, the 591,
> that is similar spec to the 511, still almost as cheap, and almost twice
as
> powerful. Might be worth a look.



> > Hi guys,

> > I have put a standard JR 511 servo on my collective (Kalt Baron 30). It
is
> > rated to 3.5 Kg/cm (I think that is about 49 oz/inch), but to get the
> speed
> > I'm looking for I'd like to run a 19mm servo horn. I noticed that
pushing
> on
> > the blades will quite easily move the servo when the power is off, so do
I
> > need a higher torque servo, or will it be all right when the power is
on?
> Or
> > should I get a higher speed servo, so I can use a shorter arm? I'm not
> made
> > of money, so I'm looking for the budget solution here!

> > Thanks,
> > Ross.