How the SA 3252 V.8.5 Worked

About: I paint, write music, and used to build knex guns. I have a Bachelor's Degree in Studio Art. - updated 5/7/2014

This is a step by step explanation of how my SA 3252 worked. The purpose is to inform you of it's mechanisms and the concept of the gun as a whole.

I am also an artist! Like me on Facebook!

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Step 1: Spool

This is a drawing of the elastic spool (top view). This was the power source of the SA 3252. A large elastic (C1) wraps around the middle. This elastic is wound around the spool by rotating the spool with a hand crank.

Step 2: Energy Transfer

This is drawing of the elastic spool, the firing mechanism, and the gears that connect them (left view). This image shows the transfer of energy from the spool (B2) to a series of 3 gears (C2), to the firing pins (D2) (there are 2 pins because it fires in 180 degree rotations). C1 is the firing elastic.

Step 3: Firing Pins

This is an image of the firing pins (notice D2 from the last image) and bullets in the mag. The circular connector spins 180 degrees each time that the trigger is pulled and fires one round.

Step 4: Trigger

This image shows the handle, trigger and a section of the trigger mech. The trigger pulls the cog around in a circle, always moving in the same direction. The movement is transferred from the cog at right to the cog at left (A3).

Step 5: Trigger Mech 1

This is the next stage in the trigger system that connects directly to the last image (notice A3). All three cogs move in unison. The left and right cogs have only four pegs (alternately placed) so as to create an alternating unblocking of the spool (the spool is unblocked on the left side, then the right, then the left, then the right and so on...). This alternating trigger system creates semi-automatic fire.

Step 6: Trigger Mech 2

This image connects directly to the last (notice A4). There are two of these mechanisms, one on each side of the gun. A4 pulls the block down.

Step 7: Blocks

These are close ups of E1 from the last image. The image to the left shows the block stopping the rotation of the spool (the spool is labelled B2). The image to the right shows the block being pushed out of the way while winding the spool with the hand crank. E2 is pushed forward by an elastic so that the block can reset and will be able to block again as soon as the operator stops winding.

Step 8: Spool Mech

I'm showing you this image again because it shows part of how the alternating trigger mech works. Notice the rods labelled A1. They are on opposite sides (left and right) and on opposite ends (front and back from this view). During operation of the gun the left one meets a trigger block, next, the block unblocks it and the spool rotates 180 degrees, at which point the other block on the right side of the gun blocks the rod labelled A1 to the right. The system repeats back and forth to achieve semi-automatic fire.

Step 9: Crank

This shows how the hand crank (F1) attaches to the spool (B2). Between them is the left wall of the gun.

Step 10: Firing Elastic

This is an image of the spool (B2) and the firing elastic (C1) and how the elastic wraps around a wheel and attaches to the front of the gun. It is stretched out over a long distance so that it can be wound many times. Every time that the elastic is wound around the spool it can fire two rounds (it takes a 180 degree rotation to fire a round).

Step 11: Pictures of the Gun

Here are some pictures of the gun to help you understand my explanations.

I hope this was informative. Thank you for shopping at Wal-mart.

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    55 Discussions


    7 years ago on Introduction

    I really liked it, too bad that it didn't work too well:(
    I got inspired, I'm gonna try something with the same rotating pin, just one of them.

    1 reply

    Reply 7 years ago on Introduction

    Yes, I've been thinking a lot lately about that mysterious appeal that so much of my work has. It seems to me that my art sensibilities are getting mixed with my engineering. And I think that's why my Z35 was so popular. It won't win you battles, but you just want to sit there all day and drool over it. It gets in your head.


    Reply 7 years ago on Introduction

    Cool, thanks. I can't respond because you featured it though, lol. So I'll respond here. 1. Yes, it's abstract art. I copied it from a t-shirt I own. 2. Creepy? Yeah, I guess so :P Supposed to be psychedelic. My own original work. 3. Batman indeed. My favorite superhero. Great movies that just came out. 4. What? Scary?, lol You think Zooey Deschanel is scary? 5. Lol, yes, I've never been better. It's my psychedelic take on the face of god from Michelangelo's "Creation of Adam".


    Reply 7 years ago on Introduction

    Yes, probably will actually. I think it's gotta be on the bucket list of every serious artist to see some of the stuff in Europe.


    Reply 7 years ago on Introduction

    lol cheers to that... have you seen my little conversation with kinetic on his slingshotgun? my concept? i'm working on it, and i believe it will work. i'm almost done with all the mechs, just have to finish up 1 thing, complete the build on the other side and run some T&Es. i believe it will be the most war worthy semi auto mech ever made. check it out, tell me what you think.


    Reply 7 years ago on Introduction

    I just read your comments, sounds great. A lot of similar things were done 3 or 4 years back but people gave up on them before they got really good because they were considered "obsolete", I hate that word, no ideas should ever get thrown out. Let me know when you post it.