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LEGO RB pistol by Tshen2 LEGO RB pistol by Tshen2
The perfected form of my LEGO fire-select rubber band pistol.

Max capacity is up to 20 rounds, though I tend to get worried beyond 13.

Its range is 6-7 meters, and pull length about 21cm.

Fire selector is located in trigger. Gun normally fires semi-auto, but secondary fire mode empties clip in one shot.

Who says engineering isn't an art? :-P
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Gennbu Featured By Owner Sep 25, 2010  Hobbyist Digital Artist
MischievousBeta Featured By Owner Apr 8, 2009  Hobbyist Traditional Artist
Sir, I have two words for you:

Pure. Genius.
Kyllian Featured By Owner Nov 30, 2008
Launcher starts to creak a bit when you pass 13 bands?
ephemerallife Featured By Owner Aug 19, 2008  Hobbyist Writer
I need the specs asap.
swemer Featured By Owner Jan 12, 2008
Do you have a blueprint on it?
ravenofpoe Featured By Owner Nov 28, 2007
dude that's awesome kudos
guitcry Featured By Owner Aug 24, 2007
Hi there, i m choosing a couple of lego works i really like or i find very interesting and yours is one of them, in the meantime i will show you my new idea,i m a lego lover and i would like to invite you to have a look to my lego works.tanks so this is my DA page: [link] and if you are curious in my blog there are more pictures about it: [link] pleaseeee leave commentssss bye tanks for the attention
bohoki Featured By Owner Jan 3, 2007
wow i goto make a micro that uses braces bands with the little gear
thebailey Featured By Owner Sep 5, 2006  Professional Artist
i have to ask : the book you've mown down those lego men on... did you read it before or after creating these weapons of mass destruction?
Tshen2 Featured By Owner Sep 5, 2006
Before, but only a few pages. My psychologist uncle actually wrote that book and he thinks I'm perfectly sane. Too sane, even.

No worries! :D
Soulforge Featured By Owner Jul 31, 2006
A feat of LEGO engineering!! I love the supressor and the "test subjects"
henre Featured By Owner Jun 14, 2006
That is so effing badass.

And btw LEGO makes little rubber tyres that can be used for friction. Just a thought.
rocksicle Featured By Owner Mar 2, 2006
Wow. I'm glad I spotted your gallery on the recently submitted things. Can you explain how the trigger works?
Tshen2 Featured By Owner Mar 2, 2006
I could, but it would be very difficult!
Okay, basically every RB gun has a gear with RBs stretched from its teeth to the front of the gun. These RBs pull on the gear's top surface and force it to turn forward. This forward motion brings the RBs closer and closer to the top of the gear. When they reach the top, they slip off the gear teeth and launch forward.

This process happens VERY quickly.. the trigger mechanism wedges the gearteeth to stop the gear from rotating. This prevents the RBs from moving towards the top of the gear and flying off. All the other bits and pieces are to reduce the gear's rotation speed to give it a moderately slow rate of fire. Without anything to prevent it from rotating as fast as it likes, the gear will release any amount of RBs in the tiniest fraction of a second by rotating at really high speeds.

The semi-auto system is a complicated mechanism (far too complicated to explain without a ton of diagrams!) which restricts the gear to rotate forward only one tooth every time you pull the trigger. The alternate fire (empty clip in one shot) disengages this control mechanism, allowing the gear to rotate, I quote, "As fast as it likes".
rocksicle Featured By Owner Mar 2, 2006
Ah, I think I understand. How do you reduce the gear's speed? I didn't know lego had any pieces that could put friction on a system like that. I suppose that's what those small gears on the left hand side are for?
Tshen2 Featured By Owner Mar 3, 2006
If I'm making an automatic weapon, I use gears to connect to RB-gear to a huge wheel, such that when the RB-gear rotates very slightly the big wheel makes one full rotation. The idea is to reduce the angular acceleration of the ear by forcing it to turn the wheel at the same time. Hence the gear picks up speed much slower, and you have controllable auto-fire!

For the semi-auto you see here.. yeah. LEGO doesn't make any parts which allow you to apply friction. That shouldn't stop you though :-P
The basic working principle of the semi-auto is I can completely stop the RB-gear's rotation by applying force to one side of the gearshaft. How do I do this? By having the gearshaft go through a series of 3 holes, where I can apply a force on the middle hole to move it out of alignment with the hole before and after it. This generates a tremendous amount of friction on the gearshaft. The exact mechanism.. that's a whole new deviation in itself!
gothate Featured By Owner Feb 7, 2006
Awesome! =D
Especially the before and after shots. I used to be able to build transformers with legos when I was younger but lost the ability to somewhere...
webkilla Featured By Owner Feb 2, 2006  Hobbyist General Artist
very nice - first LEGO thingy I've seen here... nice
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Submitted on
February 2, 2006
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