Introduction: Creating a Prop Gun From Cardboard

So I had to come up with a personal Project for Uni, hum what was I to do? I decided on making a prop gun and thought well I could try to make a realistic one but what the hey I may as well try to make a sci-fi gun. This is my first attempt at making a prop gun so I hope you like the result. After looking at countless pages on Instructables.com I decided I would merge some of the techniques I learned off there and try to make me a super gun.
 
First I had to decide on what the gun would look like, so I got out my sketch book and did a few preliminary sketches and finally decided on the look of one side of my gun, so now it was time to plan the intricate details.

Step 1: Planning

I got my sketch and scanned it into my computer, well took a photo of it because I don’t have a scanner. Next I opened up Google Sketch up (http://sketchup.google.com/), it is a great program for quick sketching unlike more complicated programs like Vectorworks. Importing the image file into sketch up, I traced it and blew it up into actual size and extended bits and pieces from the initial sketch. Then Using the extrude tool I created the different levels of the gun, creating a depth guide in the process so I knew what where the lower and higher levels. Then it’s just a matter of flipping the design around and joining it up to form the solid gun. With the new side in place I made some adjustments so it would not be a direct mirror of the other side. After this was complete I decided on where my LEDS would be placed and where switches would be located creating a diagram off a screen shot from sketch up.  Then just for fun I colored it in just to have a basic idea at what it would look like.
Using an electronic circuit simulator, available at: (http://flohuels.fl.funpic.de/Dokumente/schaltkreissimulator/circuit/) I was able to plan how the electrical elements where able to go together. See the txt  file at the end. Just open it with Notepad copy the data and go File>Import in the circuit program and paste it in.

Step 2: Materials and Tools

To create this prop we need:
 
Materials:
1x Green/Red Led
1x Small Green Led
2x blue Leds (5mm)
7x Red Leds (5mm)
3.5 mm jack bay
9v battery
9v battery clip
Cardboard
Copper Sheeting
Copper Tube
DPDT Switch
Electrical Wire
Fish Eye Door Viewer
Small Spring
Spray paint Black
Spray paint Primer
SPDT Switch
SPST Switch
Microswitch
Plastic Putty or Car Filler
Plastic Tube in varying Diameters
Trigger of some kind
Wire
 
Tools:
Cutting Mat
Glue Gun
Hacksaw
Masking Tape
Sandpaper
Scissors
Soldering Iron
Painters Tape
Pencil
Putty Blade
PVA Wood Glue
Wire Cutters
Wire Stripper (optional)
X-acto Knife

I know there is a lot of materials but that is no more than usual I think.

Step 3:

This idea was taken from gmjhowe’s Cyber/Steampunk Futuresque Sci-Fi Hand Gun
 
I printed a template off sketch up without too much difficulty onto a couple of sheets of A4 paper.  I cut it out and traced it onto the first piece of cardboard and copied this onto 7 other pieces of cardboard and glued them all together. Then I cut out groves for my slotted bars that out cover the Uv Tube and glued them in and did the same with the two areas for the gun barrels. Remember when gluing to apply the glue with a evenly you can just use your finger like I did or a brush. Also make sure you apply glue in the borders of each layer so it does not get ripped to shreds when you sand later.
 
Then I cut two pieces from thick mount board and glued them on as the final layers for the main piece. (Picture 2)

Step 4: Wiring and Building Layers

Now it was time to use my template and my depth guide to build up the layers on the sides of the gun. I also had to make room for the transformer and circuitry from the UV tube, just extending the wires to the battery and to the Neon Tube. I also cut out room for the empty half of the Fish eye door thing and stuck that in, as well as a plastic back for my trigger grip. (Picture 1)
It also shows where the wire runs for the Uv Tube, it slots back into the gun after both raised sections.
 
Picture 2 Shows the Leds being put in place for the discharge lights. While picture 3 shows all of the circuitry in place as well as most of the cardboard pieces. The Silent light is in place as well as the led tubes, the copper piping and the microswitch. To make the Led Tubes I took steven123654’s instructable on ‘How to make an neon lamp (not really)’ and appropriated it for my own needs. I went to my local $2 store and found a changing colour stick thing. I pulled it apart and extracted the bubble stick part, and then using a 5mm drill bit drilled into the end the depth of the led. Once the led was in I just used some hot glue to seal it in place. The silent light is just an old piece of red plastic covering from an old kettle, which has a red led in it. For where the wires go you can just look at my shitty wiring location diagram. The arrows denounce where it goes through the gun to the other side to reach other components, just get a power drill and using a 5mm bit slowly drill through the cardboard once all the wires are in you can plug up the holes with a bit of PVA. In picture 4 you can see everything in place and ready to be puttied up. The painters tape will help make sure things do not get covered in putty.

Step 5: Sanding and Puttying

Before you start puttying the gun make sure you give it a quick sand, to get rid of glue bumps and give the putty something more to stick to. Once the gun has been sanded you can start applying the putty in layers, once dry then sand the layer and then you can apply the next layer of putty. Make sure you sand the corners. When applying the putty make sure you put it on relatively thick so you can’t see the cardboard otherwise when you sand it the cardboard will leave fuzzy traces. I will warn you now that there will be a lot of sanding involved. If corners do not work you can always sand them down and re-apply the putty and then re-sand again.  You also might have to re-apply the painters tape as it can be ripped easily when you are sanding.
 
Next is applying a primer, it will smooth down any off the small inconsistencies in your sanding and even out the surfaces. Now it is time for painting.

Step 6:

Give the whole gun a going over with a dry paint brush to remove all the dust and the crevices and so on. Now just suspend it up on some string outside preferably on a nice sunny day. Give it a nice even covering of primer. Once the primer is dry remove the masking tape then re-apply fresh tape, as it gets thick and hard to remove the more coats you put on. Next you can put down a base layer in silver, then let that dry again and put down a black layer. Remove the masking tape and check your joins and seams to make sure they aren’t peeling to layers before; you can apply more masking tape if you wish but you don’t really need it. You can use sand paper to rub back the black and reveal the silver and using a small brush you can add silver scratches where you see fit.
If you want to know how I created that, i will be writing and instructable shortley