Advice on making these machicolations So for the longest time I've been trying some methods to create these friggin things but cant seem to find a solution that actually works.

So basically, I've constructed this tower out of a cylinder mesh with the extrudes and whatnot.  The closest I've been able to get is by using the Boolean method with those shapes.  It's looks ok without the SubSurf modifier visibility on but like I keep hearing, the Subsurf and Boolean modifiers do not go well together, which created the mess on the right.  I want to go with the subsurf because it looks too blocky without it, even with smooth shading turned on.

Anybody have any other ideas on how to approach this?  Because I'm at a loss here...
For this kind of pattern repeating around a circle, Array and Simple Deform modifiers can often be a good solution:


Create your pattern, as it is symmetrical use a Mirror modifier.





Give it an Array modifier to repeat it. Choose the Count you need, enable the Merge and First Last options.





Give it a Simple Deform modifier / Bend mode, choose an Angle of 360°. If you see that it twists strangely, you need to apply the rotation of the object.





Give it a Subdivision Surface modifier and Shading > Smooth it in the T panel. Now you can work the mesh as much as you want until you're satisfied. When you think it's ok, apply the modifiers and merge the first and last vertices with a Remove Doubles.