I'm not hugely into 1/6th Star Wars figures. I have a few, but not many. But I know there are tons of Star Wars fans, collectors, and customizers out there, so I'm passing along a couple methods of producing removable helmets for Empire troops.
The first is pretty straight-forward. The starting point in this case is a Hasbro TIE fighter pilot, though this technique would probably work for other Hasbro troops such as the storm-trooper, sand-trooper, clone-trooper, and maybe even Boba Fett or Darth Vader.
The figure shown is in fact just a thrift-store special I found nude. As you can see, the Hasbro TIE pilot is mounted on one of those awful Action Man/Hall of Fame bodies. I don't much like the proportions on these, or the lack of articulation (especially the lack of ankle rotation and head tilt).
One option on improving one of these figures is simply to remove the head and transplant it to a GI Joe body of your choice. The head-posts are completely compatible. Of course, you still have to contend with transplanting the molded glove-hands and the sewn-on costumes, but it's doable. But you're still stuck with a non-removable helmet, and that bothers me. Besides, maybe you just want a helmet to sit on a shelf or table in a diorama. So lets turn that TIE fighter "head" into a helmet.
First step is to remove the head. I used the "boil and pop" method. Dip the head into a pot of boiling water to soften the rubber, the pry it gently off the neck post. A narrow tool like a small screwdriver is very helpful in this task.
Take great cautions not to scald yourself, as the hot water likes to find its way inside the hollow head and cavities of the bodies and arms, then dribble out on you as you're working on the figure.
Here's the bottom of the removed head. You can see the opening for the figure's neck post. You can also see a ridge around the bottom of the helmet that probably represents where the real helmet ended. I chose to use that as my cut line. I've heard of people using Dremel moto-tools to cut these, but that's huge overkill. The head is soft vinyl and not very thick. I used a brand-new hobby-knife blade, and it cut like butter.
Again, use caution not to slip and cut yourself, or to cut too far into the helmet. Slow and gentle pressure is the way to go.
Here's the bottom of the helmet. The opening is plenty big for almost any kind of 1/6th figure head.
Here's the finished helmet shown on a molded-shirt CC-Joe with a WW2 head. If anything, this helmet is over-sized.
Our next project is much more challenging. Our starting point is a Burger-King kid's meal toy. These were out a year or two ago, and they aren't hard to find on eBay, or for that matter, at thrift stores and garage sales. There are a couple other figures in this line that might also provide useful helmets (I think there was a Clone Trooper and a Boba Fett, for instance).
The toy is a solid molded figure held together with those damned security screws (triangular openings in the head) that are on so many fast-food toys. (If anyone knows a source for an affordable driver to fit these, please tell me about it.) There's a light mechanism inside activated with a button on the backpack.
Since the helmet is molded as part of the whole, the first challenge is to cut it off. This would be MUCH easier if you could take the figure apart first, but lacking the right tool, and not wanting to take the time to try and drill the screws out, I just started cutting.
A Dremel tool probably would be useful here, but I don't use mine much, and I wasn't confident I could avoid cutting too much, especially in the complex little curves around the "jaw" of the helmet. So I opted for one of my favorite tools, a razor saw. I just took a lot of time and patience going round and round the helmet, coming at the joint line from all angles and taking away a bit of plastic at a time. It was tricky, but I got it done.
Here's the bottom after I cut it off. First problem, the neck opening is way too small. Second problem, the head is full of STUFF, including the LED light and battery holder. I used small needle-nosed pliers to break the tabs holding the light in and removed it. I then was able to work a small pair of diagonal-cutting pliers inside from the bottom and cut the post that contained the screw. This weakened it enough I was able to rip the two halves apart. Again, the right tool for the job would have made this so much easier.
Here are the two halves of the helmet. All the interior junk needs to go. I attacked it using two different sizes of diagonal cutters to "nibble" plastic interior parts out, and a pair of needle-nosed pliers to grab, twist, and break off what was left. Again, patience is required. Again, a Dremel tool would be an option, but be careful not to cut or grind through the outside shell.
Here's what I was left with. A Dremel probably would be the best way to enlarge the bottom opening, but I just sort of whittled things out using a sharp hobby knife, taking away the plastic a sliver at a time. Though I removed all the alignment pins, there's a lip around the edge that makes it easy to put back together properly. I glued the halves together with a bead of super-glue.
Here's the finished helmet on a CC Joe. This is a much tighter fit than the TIE helmet, but I had no trouble getting it on the Joe, and even got it on a much larger Power Team head. I think this is rather close to scale, actually. At least it looks right to me.
The nice thing about this is the you can care up plenty of extra Storm Trooper helmets, if you want them for custom projects or to make a squad of troops. Of course, you'll need to come up with armor for them. Since the original 1:1 Storm Trooper armor was made from vacuum-formed plastic sheet, and home vacuum-forming isn't difficult at all, it wouldn't be that hard for somebody to create some molds to mass-produce 1/6th Storm Trooper armor. Combine that with some simple black body suits, and you could crank out 1/6th Storm Troopers by the dozens!
Go on! I dare you! (And send me a set of armor when you're through.)