Adjusting Servo Throw

[ranger4xlt]

Anyone know about how to reduce the throw of a servo? I have a dig unit and it only needs a small throw but the servo wants to throw 90 degrees.

[gottorque]

It is usually done with endpoints and travel on a computer TX

What radio are you using?

[ranger4xlt]

traxxas tqi 4 channel intellegent radio. Says it can do all that but unfortunatly I just found out only for the throttle and steering channels..

[Dostradamas]

EPA (End Point Adjustment) will let you set where the servo stops.

What radio you runnin?

[ranger4xlt]

Traxxas Tqi 4 channel. Do they make something that can plug in to adjust seperately?

[Dostradamas]

Not that I am aware of.
Looking up the radio instructions.............

[Dostradamas]

http://traxxas.com/sites/default/fil...ual-120130.pdf

Boo It does not look to me that you can adjust the endpoints of channel 3 (shift) on that radio.

You may have to adjust the length of the servo arm to adjust throw

[ranger4xlt]

yeah that's what I figured. Thank you for double checking though. This radio would have been perfect if only they allowed adjustment for channel 3 because it's awesome being able you use my iphone to adjust everything using bluetooth.

[Dostradamas]

I have one of these :
Spektrum dx3.0
Spektrum DX3 0 DSM Radio with SR200 Reciever | eBay
It has digital EPA on all channels
Also multiple model memory.

The hacked flysky's from losikid are very cheap and versatile.

[crawlinghulls]

You could try one of these
https://www.servocity.com/html/180o_...l#.VGuqrZUtDIU

Called a servo stretcher-a friend of mine used one in a dig setup

[Dostradamas]

Servo city is a great resource!

That unit is only for analog servos.

Note: This product is not to be used with servos that offer more than 90° rotation from the factory or any brand of digital servos.

[crawlinghulls]

Note: This product is not to be used with servos that offer more than 90° rotation from the factory or any brand of digital servos.

Missed that

[TacoCrawler]

since a dig or shift servo only needs be set once.
and needs no further adjustment whence established.

I would set up the servo throw mechanically
using one of the plastic disc (circular) type servo horns.
A plastic disc servo horn is sufficient for dual set positions having no critical load...
so the strength/durability of that would be of little concern.

Establishing the link end mounted nearer the center
axis of the servo's horn will reduce over-all throw...
But it will take some trial and error to get that positioned exactly right.
The same axis consideration may also be applied to the dig/shift horn
if those might allow for re-positioning inward towards their center axis.

It's what I'd do if my radio system lacked the adjustment capability.

[ranger4xlt]

Thanks for the input guys, I think i have found a good spot on the servo arm to mount the linkage to I will just drill and tap a new mounting hole. It's so close to the screw that holds the servo horn itself on that I might have to modify some stuff but I tested it and it will work.