I was asked to create the $50 Portal Gun that Indymogul made here: http://www.indymogul.com/backyardfx/episode/bfx_20110606/cheap-portal-gun-diy
It's made from easy-to-find parts and designed to be cheap yet recognizable. The shells are made from foam tiles folded in half, the claws are made from cut-up sandwich boxes and it's illuminated with a flashlight.
After pricing up the parts which apparently cost $50, I found they were nearly 3 times that price here.
Due to this, rather than spend 3 times as much for a cheap-looking Portal Gun I decided to improve on Indymogul's attempt and 1UP them a bit.
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For this project, I'll be using:
4" PVC Pipe
60mm Acrylic Pipe
20mm Acrylic Pipe
Florist Foam
Coaxial Cable
ABS Plastic (3d printed)
Misc Tools, Screws and Paints
A majority of the materials arrived:
I started by creating some simple blueprints using the in-game models for reference.
They're as accurate as possible but I've had to make a few changes to keep the costs the same.
After this I designed how all of the parts would fit together. I managed to improve on the Indymogul design here by losing the 3" pipe and simply extending the perspex tube to function as the barrel too. This also gives the advantage of allowing the light from the middle of the gun to travel out of the barrel for added effect.
Using the blueprints and design, I modeled the additional parts in 3d.
These parts are accurate to the game within about 0.5m, so they're extremely accurate and a bit better than Indymogul's cut up Tupperware box. These will be built using my 3d printer, meaning they're pretty cheap to make too.
I created some of the parts to test the quality, here are some of the claws fresh out of the printer:
They're then sanded smooth and painted:
I know from personal experience that the claws are the most delicate part of the gun and are easily damaged at conventions by careless passers-by, so the fact these are so easy to replicate is a huge bonus.
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The next thing I wanted to improve was the white parts of the gun, which I call the shells.
Indymogul created them by cutting a foam mat into shape, folding it and gluing it in a curved shape.It doesn't look all that good, doesn't seem very strong and the foam mat's seem to be pretty expensive as far as I've found.
So rather than do this I decided to do it the traditional way; Sculpt them by hand.
I plan to sculpt the shells from florist foam, coat them with paper-mache, sand and paint.
Paper-mache is much cheaper than the resin-casting method I'd use for a more professional prop, but still gives a similar look. It's also more solid, better looking and cheaper than Indymogul's method, it just requires a lot more work. If you're willing to put the time in it really pays off.
Using 3-4 blocks of florist foam hot-glued together, I marked down some measurements to base the shape on:
Then I sculpted the shape as best I could. I've never worked with such an odd shape, but surprisingly it turned out great!
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhq83yeo16wJjuXanEICMuU3VTLEYVHIa8CQ-zkEfFtQlenhLhiPCRyUDMGxFcLQ0ldrhefRjLMgkSXedRLYtlLwvouav8Y04URlBP9pBU0QwO1SwFs4UlFoYKip1aTaCQhTXc2f8n_RL0/s400/2012-03-12+21.17.35.jpg)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjnPWnbdCyLjjdvjQRnL5FgOy6T2zdYAFlAKOSdGs9fUR9EX1S5kaxJqMVRNATdGnnhsM3rQuJolxEj_4nCZpGUqGG2kc3_txWpJhqV_BGwPGRJYCOWmKnfKgN6d8TkOPeWWsotVyIOsy0/s400/2012-03-12+23.07.33.jpg)
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Finished carving the rear shell:
The last picture shows the shell on the 4" PCV pipe which will form the barrel of the gun.
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Now I'm on to the messy, boring part. Coating the whole thing with paper.
I opted for PVA and water mix, rather than flour and water. There's no real benefit, it's just the way I was taught.
While waiting for the first layer to dry, I cut a 4" PVC coupling into size. This is what the rear shell will be attached to. It's also where the hand will be placed for carrying and the electronics will go.
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While the rear shell was drying I marked the parts of the barrel that needed cutting. Firstly I cut the 4" coupling to the right length. This is the part the rear shell will be attached to, and is where the users hand will go when holding it:
The part I've marked below will be cut out and have a transparent tube running through it to form the illuminated part of the gun. The length of the barrel also needs to be cut down to length:
Cut to the right length:
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Next I cut out the section that will house the clear barrel.
I then cut the transparent tubes to the correct lengths:
The smaller tube will be lit once the gun is completed. As it is, the light would just pass through it so I sanded it down to give it a frosted effect. This will be much better for light dispersal. The sanded tube compared to un-sanded:
I tested it by simply shining a flashlight into one end.When compared with the un-sanded tube, the difference in light dispersal is obvious:
Clear
Frosted
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Now that all of the parts are cut to length, it's time for a test-fit!
Time for a front-shell I think!
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To make the front shell, I'll be taking the same approach as I did for the rear shell.
So I started by hot-gluing some more foam blocks together and marking out some approximate measurements:
I forgot to take pictures during the middle of carving this, but it went pretty much the same as the first shell did.
Once it was done, I did another test fit to see how it looked on the gun. The results are pretty satifying:
Next, the shells will both be coated in paper to make them harder.
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One thing I've learned so far from this build;
It may look better than Indy-moguls Portal Gun and cost the same, but Indy-mogul's only took a day.
Their method involved parts and tools that are accessible to most people.
My method involves researching to create precise measurements, sculpting, days of paper mache'ing and drying, plus 3d modeling and printing, which isn't something everyone has access to or the ability to do.
Though the results are better and seem to cost the same, I've certainly paid with my time and effort instead.
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Continued coating the shells.
They're both almost done, I'm just adding one more layer so they're suitable for sanding for a nice smooth look. Here's the front shell being worked on:
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While the shells are drying from the latest coating, I printed the 3d parts for the inside of the clear "chamber".
After sanding and painting, they simply slide inside as I measured them to fit perfectly.
It's designed to hold the light-tube in place in the center of the large clear tube. As you can see, it does just that.
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Once the shells had finished drying, I put them with the rest of the gun for a test fit:
Since everything fits nicely, I decided to start painting the rear shell first. I sanded it down and used a white-gloss spray to cover as much as I could and left it to dry:
While it was drying, I took the opportunity to print some of the barrel for the gun. Once printed, they're also sanded and painted. This is 1 of 3 parts that make up the barrel:
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I've now painted the front shell too. While it was drying, I printed the rest of the parts for the barrel, sanded them down and painted them to match. They were then mounted onto the end of the transparent tube where it exits the main body of the gun. The results are pretty satisfying:
Next I sanded the the main body of the gun and painted it to. I've probably breathed more fumes than I should, but the results are worth it. I left it to dry:
Once they had dried, it was time for another test fit to see how it all looked:
It's still a little way to go, but I think I can safely say that it's better looking than Indy Mogul's portal gun.
Then only downside is that it requires 10 times the work and some specialist equipment, but it still cost same.
If you want to do this at home or in a day, then Indy Mogul's portal gun is definitely the way to go.
But if you have the time and access to a 3d printer, you can get even better results for the same price.
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Next I added the joints that the claws attatch to:
These joints allow the claws to be attatched to the gun with some adverage bolts, and means that the claws are easy to remove for transport, and replace should the worst happen.
Once they were attatched, I attatched the completed claw to it for a test run. I also added the cables to the gun as it's much easier to tell where they're meant to go with the joints in place:
I've also added a handle inside the back "chamber" which allows it to be held comfortably with one hand.
Compared to my resin portal gun, this thing is so much lighter and much more fun to play around with. I must admit, the resin gun does look awesome but I find this gun much more fun as it can be held with one hand, swung around etc. I can imagine it being even more fun at a convention.
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I printed the rest of the claws off a while ago, but it had been raining pretty much every day since then so I'd not had the chance to paint them. Well today we FINALLY got some sunshine, so I made the best of it and got painting!
The rest of the claws were painted, assembled and mounted to the gun. They're held on with small screws and bolts so they're easy to remove during transit or storage, and easy to replace if they become damaged.
Once added, I also added the final cable. The cables will have small covers where they exit the rear shell of the gun. This is because they're included in the game, and they'll help keep the cables in the correct shape.
So all that's left now is to add the covers, respray some areas of the shells and it's good to go!
Here are some pictures of how it currently looks: