About a month back, Kane realized we could use the same concept T da B used in his Ported Piston Plunger Head, and create a version that was 3d printed.
Kane then made a version for the Aabow, and it worked very well.
Revolutionizing Plunger Heads
I used almost the exact same thing for the ESLT Blasters.
I guess it works slightly different than T da B's, since it relies on the o-ring sealing against the back of the plunger head, instead of covering the holes for it to seal. While it's priming, the o-ring slides to the front of the plunger head, allowing air to pass from the front, to the rear, through the super air channels, bypassing the seal. In this 3d model, you can see the invisible air channels that accomplish this.
When the blaster is fired, the o-ring seals against the back of the plunger head, making the holes for the check valve irrelevant, since they're in front of the seal, and the o-ring seals against the back of the plunger head.
These work phenomenally well, and will be used on our blasters whenever possible. As far as I can tell, this gets as good of a seal as anything, and is a hundred times less expensive than a skirt seal. Total cost for one plunger head is less than a dollar including the printed parts and the hardware required for it to work.
Forward-Style Plunger Head
Since most people (p much e'rybody) don't build bullpups, or ESLT style blasters, we figured there would be more of use to everyone else if we made something for most traditional homemades.
These are yet to be tested, but work exactly the same as Kane's earlier version, and the current ESLT version. The plunger head is mounted with one #6-32 x 3/4" Flathead screw, which requires a hole in the end of the plunger rod. I designed this one in particular for 1/2" plunger rods, since that seems to be most common. I would do a version to accept 5/8" diameter PRs, but this design won't allow for it with the tolerances needed for the air channels. There is definitely a way to do it differently, and I'll eventually explore this.
I don't really see any disadvantages to this design, if you have a 3D printer obviously. If you'd like to pad your plunger head (which you should) from slamming into whatever it slams into, just glue/affix/leave a piece of rubber wherever your plunger head hits. If you add padding directly to the plunger head, you'll cover up the check-valve holes, and the whole plunger head will fail at it's purpose. For the ESLTs, I've been using rubber washers that just get wedged inside the plunger tube and rest on the redirect piece.
These so far seem as durable as anything else I've used for plunger heads, but time will tell. We've been using 3d printed plunger heads for over a year now, and haven't seen any problems with them degrading over time. These aren't really too much different from the normal ones we used to print, and in fact are stronger because we decided they might as well be printed with solid infill.
If you want to be one of the cool people who would like to acquire one, they are available pretty cheap on our Sales Thread.
If you want to be cooler and just print it on your printer, here are the files.
Edited by Aeromech, 23 November 2015 - 03:03 AM.