This derivative has a couple of enhancements over the original to satisfy some overly restrictive constraints.For the Renosis DeltaBot, he created a servo mount which had an offset to allow the arm to swing below the plane of the platform (http://www.thingiverse.com/thing:7554). That's a good thing.This thing takes the design a bit further and adds both an offset, and a downward angle. This gives the arm a much broader range of motion without interfering with the edge of the platform.In addition, getting the servos into the old design was quite a task, requiring the disassembly of the servo, which is not the most friction free thing to do. So, this design has an open top, which will allow you to muscle the servo into place, without having to take it apart. Although it is still a nice tight friction fit, you'll probably want to actually use some M3 screw/nuts to fasten the servo to the mount as when it moves, it will likely wiggle around in the mount.Lastly, I still use a friction fit on the shelf. You will likely want to either epoxy the mount to your shelf, or drill a couple of holes where you can use screws or other fasteners.I must confess, this is not my best OpenScad. To get the fillet, I really hacked it up. So, if you change sizes, or the angle, you'll probably have to change that little portion.UPDATE: Made the sleeve width shorter by 2mm as it was too tight on a couple of my servos.1) Print a few of these 2) Slip standard hobby servos into place 3) Slip the mounted servo onto a 6.5mm thick shelf (quarter inch plywood) 4) Rejoice!