Culex is a prototype design that I created in August 2006. It uses a spool-blowforward bolt combined with a poppet system to initiate the firing cycle. At the time this was never-before seen in a marker, though a couple markers have used this design in the time since I firat made it. It was Dye that ultimately released their version to the public first, as the Dye NT. Tippmann's Flexvalve functions similar, as does the Eclipse Etha.
At the time of its construction, I wanted to produce this marker because of its relative simplicity in terms of moving components and operation, and because I could make the finished marker into a small system. The lathe I uwas using to prototype the design was very small, so making large parts was difficult. The marker's two-stage firing assembly makes it not the most simple marker out there, but I was also interested in making something unique. Some design features were omitted in light of making it easy to produce and the design is very lean in that regard.
This wasn't designed to be groundbreaking, but rather a small homemade project to amuse me while thinking about the creation of more complex things. However, Culex does have a couple important features that are paintball firsts, the notable of which being the self-timing valve system. When I say self-timing, I mean to say the gun doesn't use a dwell "time" like other markers. Instead the firing of the solenoid is linked to the bolt movement via sensors, allowing the controller logic program to monitor the internal status, and automatically de-energize the solenoid when the time comes.
Details:
When I finished with the body internals I took it out to take some initial pictures. I drilled the eyes and detent holes later. The marker is driven by a Tadao Raider board, operating an ion solenoid. It also uses a DM membrane pad for inputs located on the back of the frame.
The marker body was made from an aluminum hexagonal extrusion since it's very easy to align hex material in my old lathe's tiny spindle jaws. The body was divided up into a front and rear section, which bolted together in the middle to encompass the internals.
Here's some pictures of the internal fabrication. Almost everything was made from aluminum on my little lathe, although at one point I started re-making some of the internals on a friend's larger machine.
After completing the internals and testing the marker for functionality, I quickly returned to the drawing board for a couple small tweaks here and there. Eventually I had revisited each of the internal components one-by-one and ended up recreating just about all of them over time. This was needed to fix some minor design considerations, and make the parts better suited for anodizing.
I initially made this thread on the Tinkering Tech forum. At the time of this writing, the prototype marker is still raw. I hope to put the finishing touches onto it someday to keep it from being ruined.