My original Fly'n'strude from tricklaser didn't fit or work well with the new E3D Titan extruder with a short-body nema17 13nCm motor. So I reimagined it.
You'll need to hit the hardware store and get some two 2-3mm threaded rods and nuts to bind the top and bottom plates together.
The holes are all 3mm, but you may need to drill bigger holes if need be.
I've recycled the original bands and the arm plate thingies that came with my flynstrude. Bungee cords can be used in place of the bands. If there is enough request, I guess I can reimagine the arm plates as well.
Infill and strength will be dependant on the weight of the motor you are using for the Titan. But honestly, it doesn't need to be that strong. I'm using the smallest possible nema17 13ncm motor, so I printed this using .4mm at 40% infill.