Dual Elevator Servos

Sat Mar 22 08:00:47 AKST 2003

You could even use 2 of the mini digital servos and save the weight. 

-----Original Message-----
From: discussion-request at nsrca.org [mailto:discussion-request at nsrca.org]
On Behalf Of wgalligan
Sent: Saturday, March 22, 2003 8:49 AM
To: discussion at nsrca.org
Subject: Re: Dual Elevator Servos

I cant see it weighting that much more then a bellcrank system.  My
bellcrank weighted about 1.5.oz  so 2 servo's at .5 oz penalty... not
enought to worry about.  Unless you build tail heavy.  Now that servo's
are programable and and transmitters can make all kinds of adjustment I
cant see why not.  Sure would make removable stabs... truley easy to
remove.  Not much more cost wise either.   By the time you invest in a
coomplete MK bellcrank setup and ball bearing connectors you almost have
the second servo paid for.

I going to do this on my next airplane so I can mkae a second set of
stabs and wings.  Mix and match.

Smooth Flying...

Wayne

 >   Keith,
> 
> I have been very happy with 2 digital programmable MCV2 micro servos 
> mounted on their sides inside the stab of my Viper 202. I originally
had 
> the MCV2 superflat (11 mm) servos which worked fine, but I  liked the 
> quicker speed and power of the micros, and they were still only about
1 
> oz each. I like the short positive nearly frictionless connection to 
> each elevator half (MK ball bearing clevis). They have held up very
well 
> and I had no problem matching the throws. I didn't even use the 
> programming feature, I just plugged each servo into a different
channel 
> and mechanically matched them as close as possible. One possible 
> advantage could be that you could have each servo work independently 
> with ailerons if you wanted to. I do that on my fun fly plane and it 
> works great (I am thinking for a multi-purpose AA plane).
> I mount the servos on their sides to a light ply and balsa sandwiched 
> rectangular plate. I use the outer balsa layer to exactly match the 
> curve of the airfoil. I then cut a hollow plywood rectangle that will 
> support the servo in the stab. The width of the plywood rectangle 
> (donut)  is such that 1/2 will be under the balsa stab sheeting and
1/2 
> is used to support the servo plate, the center is cut out for the
servo. 
> I then use a router to create a box for the servo and mounting plate 
> into the foam core before sheeting in the stab. Glue in the plywood 
> rectangle and sheet the stab normally. I then drill a hole in each 
> corner to attach the servo plate. I later added an access hatch  in
the 
> bottom of the fuselage to help fish the servo wires and extensions.
Send 
> me a message and I will e-mail pictures if you like.
> 
> Ray Morton
> 
> Keith Black wrote:
> 
> >putting servos in the stab halves
> >    
> >
> 
> This is exactly what I had initially considered on my Aries so my
removable
> stab would be easier to remove. Essentially they would be like small
main
> wings.
> 
> However all the feedback that I received seemed to indicate that this
was a
> bad idea due to extra weight, possible differences in throw over time,
etc.
> 
> I'd like to hear pros and cons from others that use used this
technique.
> 
> Thanks,
> Keith
> 
> 

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