Take a screw - I used a stainless.
Fix it on your drill or dremel.
Round the edge of the screw on a file.
Re-drill the holes of the two halves, corresponding to the diameter of the screw.
Enlarge the holes (diameter of the screw-head) ON THE OUTER SIDE OF ONE AND ON THE INNER SIDE OF THE OTHER.
Don't drill to deep, take your time.
Keep in mind that the head of the screw should'nt be deeper than 5mm of the suture line.
The bigger hole on the inner side of the other half shouldn't be deeper than 2 mm. The reason for this hole is that in the final stages you'll put some sealant in it WITHOUT SEALING FOREVER THE TWO HALVES.
Put the screw in place.
Screw it very solid to prevent any movement of the two halves.