Re: RobotChicken's Halo 3 Mk VI Master Chief, Ultra Detail, First Build WIP (many pic
Small update, lots of photos. This week has been spent working out helmet 3D printer files with SirPalesAlot and they're almost all ready, then upload time.
I mentioned in an earlier post about a different way of assembling Pepakura models. Here's a link to the YouTube video where I discovered this:
https://www.youtube.com/watch?v=TKzYY2kHIhk. I don't know if he personally came up with this technique, but I'm giving him credit for at least introducing the idea to me.
Basically, instead of gluing a flap under its adjacent face, flaps are glued under both faces along an edge. This eliminates the "step" which occurs due to cardstock thickness. On larger models this might not be much of an issue, but with smaller features the height difference can impact the model's shape, and in either case means more finishing time. Personally, I believe paper to be easier to work with than sanding hardened resin and Bondo. "Hard" edges aren't affected by this because an angle exists there anyway. It's only areas on the model that are meant to be smooth where this can help reduce the effort needed later during finishing. Since I don't care to be spending a lot of time manually cutting out flaps, here's how I have the Cameo do it for me...
First I modify the flaps in Pepakura Designer along edges that I want to be smooth on the assembled model. This is done by changing the flap shape, making it wide enough to glue on both sides of the seam and having 90-degree angles. Also, since I don't pep with Edge IDs and some flaps will now be completely separated from their parts, I increase the "Hide almost flat folding lines" threshold so reference lines are present on the parts to mark where the flaps should align.
Next, after the data is imported to Silhouette Studio, I change the line color of fold lines along the flaps to be removed so they become cut lines. (This can often mean splitting the line due to part of it needing to remain a fold line.)
After the parts are cut out, you end up with separated flaps along the edges that are to have flaps glued on both sides rather than just one side:
From the video link above I was also introduced to a different glue which I'm liking much better than Elmer's because it sets up faster, meaning less wait time while assembling parts. It's Aleene's Quick Dry Tacky Glue and stays wet long enough to align parts (unlike super glue) but sets up very quickly (unlike regular white glue). Flaps are glued along one side of a seam, then the next part is glued at the same elevation because both parts rest on a flap instead of just one part:
The photos maybe don't show it well, but trust me - the edges are WAY smoother than when gluing a flap under only one side of a seam. It takes about the same amount of time during assembly as the "regular" way, and the time spent preparing the files is certainly less time (and easier work) than filling and sanding with Bondo later on. Here flaps glued under both sides is on the left and flaps glued under just one side is on the right (hopefully you can notice the difference):
Now the real exciting thing I did this weekend was start playing around with my new Dremel Idea Builder 3D printer. It ended up taking me several prints to figure out the settings for acceptable results. My test subject was a helmet light cover dome using translucent filament. I wanted these hollow for better light transmission, less filament usage, and less weight of finished parts, so I used a 0% infill (interior fill density). 3D printing uses a concept called "shells" for setting the outer wall thickness. I had no idea how thick 1 shell is so I started out with a setting of 1. That ended up with the dome's top falling through due to not enough support material inside. Subsequent prints with incremental shells count also yielded a small hole at the dome's top. It wasn't until 5 shells that I got a good print but there was still thickness unevenness at the center so I went up to 6 shells and that's what I think I'll use for my build. With 1 shell the print took about 5 minutes, with 6 shells it took 17 minutes - still much faster than pepping, finishing, and vacuum forming. (By the way, none of the prints in these photos are "smoothed" yet from an acetone wash or sanding - these are the raw prints as they come off the printer.)
With an infill of 0% the bottom first layers end up being very thin and nearly perforated around the interior edge, which makes them very easily removed to yield the hollow lens cap I was looking for (yes, that's one of the domes with a defect hole on the right side):
But hey, RobotChicken, how do they look lit up? Quite awesome....
