Hi

I am installing these really old mechanical retracts made by i guess Royal on a my T 28 B which came with the kit that i bought from some one at RCU,i am connecting the retracts control arm directly to the retract servo(hitec 180 deg) via a straight rod but the throw of the servo is much greater than total travel of the retract control arm,i have tried adujsting the ATV on my radio ie Futaba 6XAS for that channel but it seems to have no effect on the travel of the servo arm...some one please tell me what how can i fix this problem or there is a better way of doing it,you input will be highly appreciated.


Thanks

Salman

Retract servos are not proportional and do not respond to end point adjustments made in the radio. Can't you use a smaller servo arm or drill two new holes in your servo arm that are separated by the same distance as your retract travel?

Aside from moving to closer holes on the servo arm, you can also offset the arm a few degrees. This will convert some of the servo's linier travel to a sideways travel. There may be a little binding if you offset a lot (Top Arrows) but your throw can be greatly reduced (Bottom Arrows)

If the retracts are Royals, they are a copy of the MK. I have used both, MK being the better quality, but the Royals are useable. As I recall, the linear throw required is only about 5/8 inch (you can measure this--attach a pushrod to a retract, hold it down on the bench, and measure the throw required to actuate it). Use a smaller servo wheel, and add a slight dog-leg in each wire to clear the servo hub, etc. more or less like MinnFlyer shows in his excellent sketch.

Clair

thank you guys all of your sugestions sound very logical and make sense...i really appreciate you input.

Thanks again

Salman

I am installing mechanical retracts for the first time and ran across your thread. What do you use for attachment points to the servo, in this case a Hitec 75BB and the retract mechanism's arm? Z-bend on servo wheel or arm on retract? Ball and socket? Thanks.

Check forum.