This is an experimental design where two cylinders can be joined by attaching this object to the model in question and then injecting a filler material to bind the two halves together. Its useful because you don't need screws, just glue, acetone ABS slurry, rose's metal, etc to bind with itself. The inner pathways allow at least a mechanical connection that should be strong enough.
I have not yet tested it yet but the object is parametric and should be printable by a RepRap.
The way it works, is that you connect two cylinders together by putting together the ends and filling every other hole along the seam. This should produce three filled holes with non filled holes in between. This should block air passages and allow the second filling to push material throughout the entire structure, hopefully without too much back pressure pushing material out. If this is the case, then the first filling should be left to sit for an hour or so or can be baked to boil off the solvent. Once all the holes are filled and the piece has been set to cure, it should give a satisfactory bond.
Step One: Print two of this model of the same dimensions.
Step Two: Align both printed models and try to make sure that the hollow spaces are reasonably clear of printing defects.
Step Three: Get elmer's glue, acetone ABS slurry, super glue, or your favorite epoxy ready and in some sort of squirt-able container. (I will use acetone ABS slurry in a syringe, which will be permanent)
Step Four: Inject your chosen epoxy into every other seam hole, three in total.
Step Five: let it sit until the epoxy becomes tacky.
Step Six: inject the remaining holes. Epoxy might flow out the bottom, which means its time to stop.
Step Seven: Let the epoxy cure. This depends on the binder used.
Step Eight: Your done! You just connected two pieces of plastic without screws!