5/31/2014 UPDATE: After successfully printing several white chrystal chambers, (once I made one lightsaber, everyone wants one...) I had 3 consecutive failures printing it in silver. The issue was the narrowness of the 4 pillars. So, I made a modified version with thicker pillars. (chrystal chamber with fat posts.stl)
5/25/2014 UPDATE: I made a "rib retainer ring" to snap onto body1, intended to hold the handle ribs in place without the need for glue. I also modified body1 (body1 V3 file) to have deeper detents for the rib tips, and fixed the size of the opening at the (printed) top where the "bottom" original part sticks through, and adjusted some inside surfaces to print better.
5/15/2014 UPDATE: I uploaded a new body2; I had issues slicing the first uploaded one.
After making thing 35120 (http://www.thingiverse.com/make:76835), I handed it to my son, who only gently swung it, and the tabs on body2 immediately snapped... lightsaber insides were all over the floor.
So, I redesigned body1, body2, and body3 (and the cap, which fits into body2). I started from scratch for body1, body2, and the cap, since I couldn't easily modify the .stl files enough. For body3, I was able to make cuts to the mesh, and add small mods to it.
The result is a no-glue outer body (except for the ribs on body1, which I haven't done yet on the one in this photo). I've been thinking about a modification to allow the ribs to "snap in" so they too will not require glue... maybe a future remix. :)
The first thing I did was widen and thicken the "tabs" on body2 so they are much stronger, and will not snap off. Next, I put a 45 degree edge on the "inner lip" to aid in printing (avoiding a 90 degree overhang). Since that side faces away from the beam chamber, it has no effect on the fit of the internal parts. Lastly, I added a small ridge to the end where the cap fits on.
The cap I created has a matching ridge in the slot that body2 fits into. It is intended that the cap be printed with flexible filament; it's plenty stiff, but has enough give to snap onto body2, and engage the ridge, so that no glue is required to hold it on.
On the original print, rather than trying to snap body 2 onto body three (and probably break the tabs), I had cut away three sections of the rib on body 3, to allow body 2 to attach with a push-and-twist action. Since that worked well, I modified body3 to print with the missing ridge sections, and with some vertical ridges to make a stop for the twist action. I did that to both ends of body3...
I also modified body1 so that it has a "ring" at the bottom (as printed) that will also push-and-twist onto body3. It also has small detents to hold one end of the ribs, so that only the opposite tip needs to be glued down.
Finally, I included a version of the original crystal laying on one side that will print with no support.
I also modified the (internal) chrystal_chamber_cap to avoid the 90 degree overhang. The original did not fail to print, and was usable, but the improved part prints cleaner (see photo).
The "cap" is intended to be printed with flexible filament. If it is, it should just press-fit onto body2. If printed with normal filament, it should fit if you remove the "ridge" on the matching end of body2 (of course it will require glue then).
I also recommend printing the "rib retainer" with flexible filament. It will work with normal filament, it will just be a very tight fit (I actually made half a dozen lightsabers using normal filament for the rib retainer; it was only after one broke while sitting on the desk, that it occurred to me that the part was better suited to be printed flexible).
You still need to print the inside parts from the original thing:
I printed all the "outside" parts with a brim to make sure they're well anchored; especially body1, due to it's height.