Spiky bits are cool, I think we can all agree. Sometimes, they have practical uses as well. For instance, did you know that all the spiky bits on old greenhouses were not merely decorative, but served to prevent birds from perching on a greenhouse's gabled peak? After all, one doesn't want one's greenhouse roof to be made opaque from avian excrement!
Of course, for those of us who enjoy the tabletop wargaming hobby, spiky bits are usually an indication of a chaotic alignment - maybe not chaos per se, as any 40K player knows how much the Orks and Dark Eldar love spikes. Anyway, after making my most recent chaos airship (adorned with spiky bits, of course), I decided to share this method, in case anyone else is into this sort of thing. For the purpose of this little text lesson, I'm going to use an updated version of the Zaphnora's conning tower.
I recently modified the lower platform, since I wasn't particularly happy with the way the original turned out. Well, that's not quite true, it's just that the old version doesn't really fit with the upper platform. The old version had all the spikes sticking straight up:
As you can tell by the relatively short part tree, this was a fairly simple and straightforward model to make. The upper platform, on the other hand, was a bit more complicated, and the updated lower platform was more complicated still, as you can see by the length of the part tree (pay close attention to the size of the scroll bar and the number of extrusions):
Now, to get into the actual lesson. If you intend to make a platform with the spiky bits splaying in many different directions, there really is no quick way to do it unless your platform is circular, or an otherwise regular shape that would allow you to use a circular pattern of a single spike. However, there is still a method beyond "freehand design," if you want to get any sort of regularity. Dem spiky chaos boyz don't just put dem spiky bitz on all random loik da greenskinz!
I will use the upper platform as a simple (if this is simple, what do I consider complicated?!) example of a regular pattern. All of these spikes are splayed out at 18 degrees from a centre point. Therefore, I use the offset tool to create a shrunken replica of the deck profile, and created lines to all the places that I wanted to place the upright components:
With my software (Autodesk Inventor), it's possible to connect midpoints as well as endpoints of lines. However, that will get only three upright components per curved section, so the curves must be split if you want more. A single split at the midpoint, where lines were placed, was enough to give me the results I wanted, but if you want odd numbers, you may have to get creative. I like to use circles at midpoints, for instance, if I want to divide a line in thirds. If you're not sure what I mean, let me know, and I'll explain it in a comment.
For the updated version of the lower platform, however, I didn't want all upright components splayed out the same amount. In the back, I wanted them sticking straight up, at least when viewed from the side.
The layout of the sketch was similar, except at the back of the deck:
The outside line, offset from the deck profile, is meant to represent where the railing is supposed to go. A close-up, meanwhile, shows the exact location and orientation of the upright components:
In the case of all the platforms I've made so far with these splayed-out spikes, the idea is the same: there is a square at the exact location of the upright component, with its sides parallel to the lines that connect the inner and outer profiles at regular intervals (or wherever I want to put the upright components). It is crucial that the sides are parallel, because of what the squares are for:
The squares all get revolved around one of their sides the same amount that you want the upright components to splay. So far, I've been using 18 degrees, but this particular square got only 9, since it is in an intermediate location. All the others on this platform got 18.
After revolving all the squares, a cross section of the upright components gets sketched in (just a circle in this case, but I've done squares as well before), and extruded. If you want to create a curve between the points of the spikes, as I did with the upper platform, just fiddle with the length of each extrusion. Since you will be starting from a different orientation each time, it's not possible to simply make one of these and then make a pattern of them. After all the upright components are in place, The deck gets cleaned up by simply duplicating the extrusion that made it, cleaning up the mess left over from the revolved sections.
Once that is all done, the railing gets added. Since I already had it sketched, I just copied that part of the sketch and placed it on a work plane offset from the deck to get the desired height. Then the railing gets extruded, any upright components sticking up above it get sharp points added in the form of tapered extrustions (cones, in this case), and then everything gets mirrored and "painted."
This looks much better than the old one. Going from vertical to splayed and back to vertical just didn't work for me. If you follow the line from the front of the upper platform, it is almost perfectly continuous with the lower platform. At the very least, it's parallel. The spikes themselves don't match (the lower platform has cones, the upper platform and flying bridge both have pyramids), but that doesn't matter as much.
I don't imagine that there is a lot of demand for this specific skill, but given how people like to customise things (particularly wargaming miniatures, since building the army is half the fun), I figured I'd share it. This is one of those lessons that is better suited to text than to video, because the idea is simple, but the execution can drag on to the point of tedium.
If you're interested but found this to be clear as mud, feel free to ask questions.
