Controlling angle on modded servo (sigh.. I know..)

Hi,

First off, I know the problems with this kind of task but I'm working on a project were I can control my blinds with an Arduino and the SG90 servo.
The blinds are of the tilted types, here's a pic: blinds

And I need the servo to be able to turn 360 degrees, therefore I will mod the servo later when I've confirmed it is in some way possible to control the angle.

I'm thinking controling the angle with seconds maybe? Although, I need to control them with a potentiometer. Is it possible to control the servo with seconds, using a potentiometer to get to the wanted-ish anlge?

I'm so sorry for my bad text composition. But I hope you all will understand.

But to wrap up my problem:
I want to turn my modded servo to an angle with a potentiometer.

EDIT: Change of plans!
I'll use buttons to control the blinds angle instead. I think it's much easier to handle.
Anyway, I still wonder if anybody has been able to ish-control their modded servo to an specific angle?

If you want to have control of the angle over more than 180 degrees you should probably use a sail winch servo. Most of them can turn 3 revolutions with position control.

If you convert a standard servo to continuous rotation you lose the ability to control the angle unless you add the considerable extra complexity of a rotary encoder.

Another option might be to add a 1:2 gear train to the servo so that the normal 180 degrees translates to 360 degrees. However the torque will be halved.

...R

SG90 is a micro servo with a max pull/push of 1.8 kg with the operating rod or whatever placed 10mm out from the centre on the servo arm and 4.8v supply. (1.8kg/cm). Are you sure that will be enough for driving " blinds"? I would imagine Robin2's suggestion to have a much greater force with perhaps a bit up your sleeve so to speak.

As robin says get a winch servo.

Mark

Yeah, I guess you are rigth. I will consider those alternatives! Thanks!