two different servos, one surface?
 

I am putting a 8411 155oz servo on the same surface as a 811 54oz servo will there be problems if there are a slightly different speed? Will there be a problem even if they are the same speed? Is there a way I can prevent them from fighting eachother and be sure they have the same travel without a matchbox or a servo programmer?

two different servos, one surface?
 

Willy,
yes, maybe, no.

Why?

two different servos, one surface?
 

Actual practice says " absolutely NO problems -in fact a very good idea.
There has been plenty of Bull S---about speed differences being a problem.
Try this:
mount both servos end to end.
hook em up in a Y harness - put a JR wheel on each output arm.
now add one of those little brass dohickys to each wheel, that allows a piece of wire to connect them together.
Fire it up
make sure both servo outputs are lined up the same.
slip the wire into one output and tighten it.
allow the wire to slide in the other one.
Move the control stick slowly back and forth- full travel.
Unless there is a problem with a particular servo --both should travel the same amount and the wire which was floatin, should stay in the same position -on it's servo.
If that all looks OK- tighten the loose wire connector.
now move the control - -there should be no buzzing at any position held.
The differences in SPEED are meaningless - as long as the held positions are the same.
Why?
because the servo- in actual use , never gets to travel at full speed.

Have we used these setups ?
Absolutely -- in fact the best setup seems to be a digital -say a 8411 -in the outboard aileron position and a 4721 on the inboard.
There is no servo "fighting" due to the more broad "center" of the 4721.

two different servos, one surface?
 

Why would you want to do this?? To save money?

two different servos, one surface?
 

Save money?- No -
Save conflict of servos -which results in high battry drain and worse yet - servo heating !
The present servo setups of multiples , hard coupled to one output , is a risky setup - If you can't do it perfectly - Don't do it.
The digital / analog combo -or using "loose " center digital servos, gives the servos a chance to "resolve" as intended.
Ideally, there would never be more than one servo -to any given output.
I am doing a 50% bipe at the moment and the kit mfgr recommends a box full of servos -
We will reduce this setup by half.