Hello everyone! I suppose I'm back for a bit. I finally got my KNEX back just in time to start building for another contest, so here goes!
This gun is the ZipDart V.2. It takes some of the same principles of the first ZipDart, but completely reimagines how the mechanism should work to make it both significantly more reliable, and a lot more fun to use.
Range -- really don't want to talk about it (maybe 40ft, not as proud of this part)
Gizmos and whatchamacallits:
-- True trigger (can't believe I still have to say this :P)
-- Zipdart (and all that entails. If you don't know what this means, check out the Zipdart V.1)
-- Loads of other 'shtuff
P.S. I'm deeply sorry for any out of order images or double images or extra images or the like. Every step of the way Instructables was thwarting my efforts with poor website design and crashes. There were just more images than they necessarily planned to support per step.
Note of skippable cut parts:
The cut white rods in the top rail can be completely ignored, and are only there for prototyping and when initially building the thing
The cut brown connectors on the loading arm don't need to be cut (can catch, but this is a very minor issue)
The cut orange rod on the bolt handle is functionally unnecessary (but makes assembly slightly easier)
The cut white rod for the mag pusher isn't necessary, but makes it lower profile and generally less likely to catch while handling the gun
The cut blue rods throughout the main body are not necessary for function, but make repair and assembly significantly easier
Other than that, if something doesn't look like it needs to be cut comment and I'll get back to you. It may be a carryover from prototyping, or it may be necessary for actual function but I'll need to analyze each piece to check and spot checking is way easier than checking the entire build.
NOTICE: for any people looking to get into KNEX guns, I'm open to any collabs and really want to get a few more people on here building them before I leave for college in the fall. It's a community that still has unexplored areas and concepts but has almost no interest anymore. Even if it is just to go over building techniques and other concepts, that would be great. I see plenty of block trigger guns being posted, so I know there are people who want to get into it, but there are other concepts that haven't yet been used to death.
Even without a collab, a couple things I haven't yet seen executed well (or haven't been fully explored):
Horizontal magazines (inline with gun)
Hammer action guns
Repeating slingshots (yes, there is more here to explore -- a good single-action-prime one hasn't really been made)
Full-auto guns with KNEX projectiles
Open bolt bolt-action designs
Clip (not magazine) fed guns
If you want to get into things, build a few more advanced guns then just jump right into prototyping. More new content is pretty much always a good thing.
Step 1: Barrel Assembly
In this step we will complete the barrel assembly. I don't know where trouble spots may be in terms of building it, but I don't want to write pages of unnecessary text. So, if you have trouble building it just comment at the end where you have trouble and I'll try to reply ASAP.
Step 2: Main Body
For the piece in the third photo, put a fairly thin layer of electrical tape on. Not too much, just enough that it serves to add a bit of grip.
The bit in the 8th photo has electrical tape around the perimeter of the orange piece, but not on the green connector. Use a knife to make sure the tape doesn't overhang the edges of the piece.
I apologize for the last image here, unfortunately there were too many images and I can no longer access/delete it from the Web UI for Instructables. That last imamge was supposed to go earlier, as you do indeed need to build two of those, but it's for one side and the other of the gun. Basically, build two of what is in the first image and ignore the very last one.
Step 3: Bolt Assembly
Yes, the cut parts here are required save for the yellow rod in the handle (that just makes assembly significantly easier.)
Step 4: Top Rail Assembly
Sorry I didn't fully disassemble this for the instructions. It was hard to put together (physically--it wasn't very complicated, just hard to force some of the pieces together) but should be fairly easy to infer how it is built.
Step 5: Magazine
Crimp the green rod with the blue spacers at either end so it stays in place but lets the spacers move freely (tape may also work)
Step 6: Band Arms
If I say "mirror" it means make that part plus a mirror image of that part with the plane of reflection being your monitor/display.
Step 7: Putting It Together & Bands
If you have any questions, just ask.
For the shuttle, you can use semi-elastic paracord. Sew it into a loop at either end or just tie it to some bands. Attach the bands to the yellow rods on the band arms and fine tune it yourself as bands vary and I can't give you a catch-all solution here.
BTW sorry about the little changes that occur in this step. I didn't realize until I had done that entire section and it didn't make sense to redo everything.
Step 8: Finished!
Now that we're done with assembly, time to try it out!
First, after putting on all the bands make sure that the grey connector + green rod + grey clip thing on the end of the loading arm inside the magwell is sitting inside the hole made for it at the front of the magwell and not flopping around.
Now, load the magazine. Take orange connectors and attach a green rod to one end. Load the magazine by pushing them in with the green rod toward the end with the green connectors. Now, with the loading arm all the way to the front (resting position) insert the magazine. Put the rear of the magazine (with the broken red connector) so that the white rods rest on top of the grey rollers at the back of the magwell. Now, spin the magazine upward and into the gun. It will click into place with the grey connectors that form the latch at the front of the magwell. If you need to remove the magazine, push upward on the grey connector sticking out at the front and rotate the magazine out of the magwell (reverse-AK style.)
To prime the gun, pull the main bolt all the way back until the paracord is stuck nicely on the ratchet. Now, pull the loading arm (lower bolt) back until you hear a click and the trigger pops forward a bit. Now release slightly until you hear another click and the ramp arms disengage. Now, pull it the rest of the way back and release and let it go forward.
Before firing, pull the trigger slightly so that it loads the round into the chamber, then pull it the rest of the way to free the ratchet and launch the projectile.
If you get a jam, take the top rail off by taking it out of the y-clips. Now, create a break somewhere along the top of the main bolt and pull the paracord out through that hole. The main bolt should now come out, letting you get at most anything that going through the magwell didn't let you access.
Have fun with your ZipDarts everyone!