Summary

Every servo comes with slightly different sets of horns. Here are two adapters. The thicker one hpefully covers the span on the back of the servo to the bearing.

Instructions

I think filling the cavity of the ROFI printed parts would work too, but I'm going to try this first, and possibly stop by the Hobby People and get the right horns.

You will want to print these at least four at a time, to give the layers time to cool off a bit. Once cool, glue them onto the horn perimeter.

You should use a couple of washers to set the spacing on the larger radius. I did not include this feature in the model so as not to require that it be printed from the hollow side. This might make it difficult to fit.

YMMV

ROFI Servo Horn Adapter