Desired degree of rotation on Futaba S-3003 servo

[joshidharmesh]

Standard Futaba S-3003 servo has 90 degree of rotation. I want 180 degree & 360 degree of rotation by modifying this servo.

Can anyone help ?

Thanks,

Joshi Dharmesh

[vintage1]

180 is possible by padding out the ends of the servo pot with resistors.

360 is beyind the ability of any potentiometer to handle without binding. Most are at best 270 degrees. I suspect you will need to build a special here..

[andrew b]

Maybe put a little gear train mounted ON TOP OF the servo, like a 1:4 ratio, depends if you have the space, although with plastic gears it shouldn't weigh too much :)

http://www.mfacomodrills.com/gearboxes/multiratio.html

[ImaBiggles]

http://www.nw.com.au/~jspence/Mad_About_Multihulls/3.htm

[sfsjkid]

Joshi, I opened up this thread with great hopes for I have a similar need, though mine would be for a 3004 sized sail winch like servo, ie more than 360 but also limited somewhere via internal feedback. Life would be so easy!

Anyways, your post prompted me to open up my Futaba FP-S5801. If you'll excuse my fingers, you'll see that the feedback pot is mounted vertically and off to the side. In place of the normally mounted pot is a worm drive gear that turns the gear on the pot. I hope this will help with ideas.

It just occured to me that you could modify this one as vintage1 described, assuming you have the space to mount the servo. It is a little pricey, at ~$150, but have seen them on ebay for half that. Another problem is that it needs a 5-6 cell battery, but has a 6V/1.5A BEC and power switch. Hitec makes something similar but have not researched the particulars on that.

Good luck!

[sfsjkid]

Gees, I'm slow tonight, if this is an R/C application, all you would have to do is set your endpoints, for anywhere from 0 to ~3.5 revolutions!

[joshidharmesh]

I got continous rotation by modifying final gear of the servo. I got it from Kite Aerial Photgraphy site. Intersted may visit this link http://www.kaper.us/basics/Bas_360_4_R.html

Joshi Dharmesh

[Hell-e-Guy]

I solved this problem once for a friend by replacing the original potentiometer to a multi-turn potentiometer and placing it outside of the servo box on it's axis.
I'll ask him if he has any pictures of the setup.