Introduction: The KING of K'nex RBGs: the Gnasher Shotgun
This is my favourite gun I have ever made (out of k'nex). It is a working model of Gears of War's Gnasher Shotgun (my fav video game gun).
This is a 8 shot semi automatic RBG. Different from other RBG's, you must break the lever (bring it forward) to initiate another shot. The gun is capable of taking heavy pressures, so feel free to lay on the elastic power.
I apologize in advance for some of the pics having poor picture quality. Just ask if you need clarification on any of them.
Hope you guys enjoy this as much as I do.
Ps: if you hold the lever forward and then shoot, all the elastics fly off at once.
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Step 1: Build the Hand Guard (lower Part of the Lever)
Build exactly what you see here to construct the hand guard part of the lever (the part you put your hand in. The upper part also acts as a trigger guard.
Step 2: Build the Dog Carrier (upper Part of the Lever)
Build what is depicted below. This part moves the function that allows the shotgun to be a semi-auto.
Step 3: Build the Cog Mechanism, the Trigger and the Cog
The Cog (right)
This is where all the elastics fit on. Note the double white combination for more strength.
The simple yet strong mechanism that initiates the firing
Cog Mechanism (middle)
This part here directly touches the cog when loaded, and is rotated out of the way to allow the gun to advance the cog. Note the white rod (acutally black)- make sure this part is inserted through the three grey connectors- it gives the gun its strength to withstand pressures.
Step 4: Build the Foreward Thing (does Nothing)
Build this part. It is added onto the near end of the barrel. It exists purely for aesthetics.
Note: whenever you see the large blue panel, it is simply there to prop up the part- it isnt part of the design.
Step 5: Build the Foregrip
This is the part that you hold onto. It is very rigid for maximum grippage (is that a word?)
Step 6: Build the Pistol Grip
This is the pistol grip. You will need a bendy-white rod (actually purple if you have it) for the thumb rest.
If this grip seems too thin, it technically is, because the back of the lever thickens it when it is unbroken (in the rearmost position)... just trust me on this one.
Step 7: Build the Mechanical Walls
These two walls house the mechanics of the gun, so it is especially vital you don't screw this up.
Step 8: Beginning Assembley: Attach the Grip to the Right Mech. Wall
Here, simply snap on the grip to the right mechanical wall.
Note: I didn't realize you needed the green connector, so add it in. this will snap into the trigger axle. (shown below)
Step 9: Insert the Cog Wheel and Trigger
Insert the Cog wheel into the cnetral white (or black) connector. Make sure that the blue spacers are still in place.
Instert the trigger into the white (or black) connector closest to the grip. As noted earlier, the green connector snaps into the trigger axle. (the side not snapped into by a grey connector)
Step 10: Attach the Upper and Lower Parts of the Lever
Now, attach the upper and lower parts of the lever.
Step 11: Insert the Lever
Now, insert the lever into the leftern white connector. Make sure it is the blue rod, not the yellow rod with the spacers.
Step 12: Build the Mock-Loading Port (almost Forgot!)
Build this simple device. When broken, the lever will bring this down-mimicking the real action.
Step 13: Connect the Cog Mechanism and the Lever
Simply connect the two grey connectors with the green rod to have the lever mechanism complete.
Step 14: Insert the Mock-Loading Port
Insert the mock-loading port into the right-most green connector near the thumb guard. Then, with slide the grey connector at the end of the movement arm into the white (or black) rod located just below the lever axle.
Step 15: Attach the Left Mech. Panel
Now, attach the left Mechanic panel. Make sure all the axles and rods line up properly so everything works smoothly. You can try out the action now.
Step 16: Build the Top Rail
Simply build this top section of the gun.
Step 17: Build the Barrel
Now, this may be complicated, but try it out. Build this system, and it will become the barrel.
Step 18: Build the Mock-lever Arms (forgot This... Whoops)
Build this simple attachment. It will be added in the next step.
Step 19: Attach the Mock-lever Arms
Attach this to the protruding green connector on the middle of the lever. Then, connect the green rods on the end of the green connectors to the grey connectors (45 degrees) on the top of the now concealed lever.
Step 20: Attach the Foregrip to the Barrel
Now, snap on the grip- three of the orange connectors behind the first white (or black) connector.
Step 21: Attach the Top Rail to the Barrel/Grip Assembley
Now, just connect the top rail to the barrel assembley.
Step 22: Attach the Left and Right Sides of the Gun
Now, connect the left and right sides of the gun where you need to.
Step 23: Attach the Useless Forward Attachment
Before you can attach the piece, you need to install 4 small black connectors (see below). Then slide on the attachment with the corresponding holes in the upright parts.
Step 24: Slide in Four Blue Rods Into the Top of the Gun
Now, slide in four blue rods into the corresponding holes. The rod at the rear of the gun requires three grey connectors to be snapped in, and the forewardmost blue rod snaps into the 45 degree slot of the upright yellow connector.
Step 25: Attach Mounting Connectors Onto Blue Rods
Now, attach connectors in the fashion as you see below, sorry about the bad pics.
Step 26: Attach Upper Rods
Now, attach mainly grey rods into the connectors you just installed... you're done construction!
Step 27: Atttach Elastics
Now, just attach elastics onto the trigger and cog mechanism.
Step 28: Loading
Now, to load, break the lever forward, and hold it there.
Load an elastic onto the rearmost accessable notch on the cog wheel. To load another, rotate the cog wheel back until the trigger locks it into the next place.
Then, return the lever into the unbroken position.
Step 29: Shooting
Now, pull the trigger and then break the lever until you hear a click and see the cog rotate foreward to re-advance the cog wheel.
Or, as I mentioned earlier, you can break the lever, hold it there, and then pull the trigger to shoot off all loaded elastics at once.
Now go shoot stuff.
Step 30: MECH. UPGRADE: Overview
With this upgrade, I reinforced the lever and dog carrier mechanisms because under intense pressure, they fail. So, without further adieu, here it is.
All the parts you see have already been upgraded, so try and follow along the best you can, I'll try and be descriptive.
Step 31: MECH. UPGRADE: Remove Mock-Lever Arms
Simply detach the moch lever arms to gain access behind the mechanical wall.
Step 32: MECH. UPGRADE: Remove the Right Mech. Wall
Remove the right mechanical wall to gain access to the lever and dog carrier mechanims.
Modify the existing mechanical wall you just removed to look exactly like the one below.
Step 33: MECH. UPGRADE: Remove Existing Dog Carrier and Lever
Now, just remove the existing dog carrier and lever mech so you can modify them.
(shown is the already upgraded dog carrier and lever)
Step 34: MECH. UPGRADE: Modify the Dog Carrier
Now, modify your existing dog carrier so it looks like this one. Also, build the extra 2 arms. (shown below the dog carrier)
Step 35: MECH. UPGRADE: Modify the Lever Mech
Now, just modify your lever mechanism so it looks like this one.
Step 36: MECH. UPGRADE: Attach the New Mechanisms
Now, as before just attach the mechanisms together using the arms. Then, just slide the extra arms on the yellow rod and white rod respectively. (they do not snap on, so they may fall off as you put them in the gun, but once in they retain their positions)
Step 37: MECH. UPGRADE: Modify the Left Mech. Wall
Now, modify the left side mechanical wall so it looks like this one (in the background)
Step 38: MECH. UPGRADE: Insert the Parts
To insert the parts, just re-position the parts as you did before, with the exact same axle holes. (don't forget to line up the mock-loading port arm with the old axle!)
Step 39: MECH. UPGRADE: Attach the Left Mech. Wall
Now, just re-attach your newly upgraded left mechanical wall with the old snap areas.
Step 40: MECH. UPGRADE: Re-attach Elastics and Mock-Lever Arms
Now, just re-attach the carrier elastic and trigger elastic with in the old places, and the mock-lever arms, and you successfully upgraded your Gnasher to a stronger model.