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Big Boy

Posted: Wed May 05, 2010 6:17 pm
by Gaderelguitarist
I apologize for neglecting to post any recent builds, but here it is.

Big Boy:

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Barrel: 1.5" x 5' PVC
Chamber: 3.5" x 30" UHMW
Ignition: Grill Ignitor, single spark gap
Loading: Threaded breech
Dressings: Wooden thumb-hole stock with horizontal hand grip. Picatinny rails for laser and signt.

Big Boy has rapidly become my favorite cannon. For one, it has stage presence. Whip this mother out of your truck and people will pay you some attention. Secondly, while being a spray and pray, it has shown a violent streak of consistant launches. Finally, it has everything I like in a cannon; relative portability, ergonomic approaches, and black paint.
It was the first that I decided to modify fitings for in order to build. The chamber is sealed off at one end by a lathe turned piece of wood that is sealed with epoxy and held in with screws. The front threads were a female threaded PVC adapter that had to be turned down to fit inside the UHMW pipe and then attatched with screws.

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Shown broken down.

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Here is the breech. Simple construction allows for easy repair and potential for duplication.

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The muzzle break is just a coupler thats been eaten at by a forster bit.

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Front rail meant for a laser.

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I know I could have hidden the wires, but I like the look of the wires sticking out. They match the triggering button and I can't resist that sort of thing.

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Down the chamber.

I have opted to keep this one a simple spray and pray because of the simple and pure nature of using it. No formulae, no complicated metering systems, no electronic overkill; just a nice, simple, fun cannon.[/img]

Posted: Wed May 05, 2010 6:24 pm
by geardog32
nice work. i like the stock and rails alot.

Posted: Wed May 05, 2010 6:30 pm
by metalmeltr
Nice cannon, I like the paint!. Where did you get UHMW pipe? That is an unusual choice for a chamber, why did you decide to to this?

Posted: Wed May 05, 2010 6:42 pm
by clemsonguy1125
Looks great ,how loud is it. What kindarange are you getting.

Posted: Wed May 05, 2010 7:19 pm
by Gaderelguitarist
Thanks for the nice comments, guys!

@metalmaltr:
I found a length of the stuff a while back. Construction companies use the stuff as electrical conduit for street lights in my neighborhood. It's about 1/2" thick so I figure I'm as safe as I'll ever be.

@Clemsonguy1125:
It's loud :D . I'll try to capture the sound in a damage video this weekend if the weather is nice. As for range; my friend and I were considering buying a contractor's measuring wheel to get an idea. I would say that it can put a potato well over a footbal field on a second of hairspray.

I forgot tyo mention in the main post that along with the flat black paint is a textured "iron" colored paint. The surface is similar to sandpaper, and this is picks up every spec of dust, which I'm hoping will give it an aged look soon. It also helps with loading, as it provides a solid grip of the two pieces to be torqued.

Posted: Wed May 05, 2010 7:25 pm
by Lockednloaded
you should definitely make a fuel pod fueling system, it would not take much time, and you would have practically add nothing. You would probably get an increase in power and consistency

Posted: Wed May 05, 2010 7:39 pm
by clemsonguy1125
Or at least add a fan

Posted: Wed May 05, 2010 7:53 pm
by Gaderelguitarist
I respect the want for more power and consistency, but I just want to keep this a simple spray and pray.

I have considered making a more advanced version, and I do still have a section of the same UHMW pipe ready to be worked with. It may come in the future.

Posted: Wed May 05, 2010 8:17 pm
by mark.f
You could keep it a spray and pray and add consistency as well.

Add a mechanical mixing device. This can be a chunk of plastic that won't exit the chamber when inserted through a threaded fitting.

Use butane. Add a spray top from a can of deodorant or another aerosol to the butane stem, and find the right time spraying which provides the best results. Use that time from then on.

Good job all around, though. The fabrication looks well executed.

Posted: Wed May 05, 2010 8:30 pm
by Gaderelguitarist
Thanks for the suggestions.
I use that method of feuling as it is, so the switch to butane won't be a big deal. As for adding moving parts, I'm a little skeptical. Mind you, I could do it, but it seems that it would also be just as simple to just deal with more electronics and add a battery powered.

Fabrication on this was a secondary concern. I still find it lacking, but am in no position to want to modify it any further. Perhaps on the next build I'll pull out all of my tricks and make one thats up to my skill level.

Posted: Wed May 05, 2010 8:36 pm
by Gun Freak
I like the way it is already and I don't really think you need to upgrade. Spray and pray is fine if that's the way you want it to be.

Posted: Wed May 05, 2010 8:40 pm
by mark.f
As for adding moving parts, I'm a little skeptical. Mind you, I could do it, but it seems that it would also be just as simple to just deal with more electronics and add a battery powered.
Throwing a 1-1/2" pipe cap in the chamber is more complicated than adding a fan? :D

Posted: Wed May 05, 2010 8:47 pm
by Moonbogg
Nice cannon. UHMW Chamber? Never seen that before. 1/2" thick seems plenty safe. That stuff is pretty tough and doesn't tear easily.

Posted: Wed May 05, 2010 8:57 pm
by Gaderelguitarist
@Gun Freak:
Thank you for understanding :roll:

@mark.f:
I never said complicated, merely that it would be just as SIMPLE to do a standard chamber fan. Regardless, I doubt that I would do either on this one.

@Moonbogg:
My thoughts exactly. Although I would have thought that using wood as a construction material would have people feeling a little... off kilter. Granted I have seen most of the wooden monstrosities on this forum.

Posted: Wed May 05, 2010 9:12 pm
by theBOOM
Very nice gun, I specially like the textured paint you used on it, looks original yet cool.

Why not slap a quick disconnect onto it and make an external fuel meter for it? That should give you more of a kick...