Boom!  The classic potato gun harnesses the combustion of flammable vapor.  Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
			
		
		
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								Kennymester				                
							 
	
        
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								brother361				                
							 
	
        
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								 Sun Aug 17, 2008 11:19 pm
			
			
			
			
			im pretty sure thats a dwv tee i think you would be fine but its alwasy good to be on the safe side
            
			
									
						
			
						 
		 
				
		
		 
	 
	        
			
		
		
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								Stifler69				                
							
 
	
        
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								 Sun Aug 17, 2008 11:27 pm
			
			
			
			
			Wow man what an awesome potato gun !!!
You are so not a first time gunner from what I've seen here haha.
But yeah really nice gun, you should get some action of it on film.
            
			
									
						
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								starman				                
							
 
	
        
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								 Sun Aug 17, 2008 11:34 pm
			
			
			
			
			A little bit of a Rube Goldberg setup you have there. However, you've got it working consistantly and that counts for a lot. The propane canister looks funny hanging out there in seeming mid space.
Do something constructive with your battery holder and replace that duct tape with a hose clamp or even tie wraps.
Congrats on building a successful advanced combustion!
            
			
									
						
			
						 
		 
				
		
		 
	 
	        
			
		
		
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								Kennymester				                
							 
	
        
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								 Sun Aug 17, 2008 11:47 pm
			
			
			
			
			Stifler69 wrote:Wow man what an awesome potato gun !!!
You are so not a first time gunner from what I've seen here haha.
But yeah really nice gun, you should get some action of it on film.
No I really am I first time gunner. I just did a a lot of research and calculations before I did it. =)
I have to make it a priority to tighten up the design a bit. It's not too much of a problem to make some extra trips to the hardware store considering I work there. Lol
I'll see if I can get a video of it tomorrow.
 
            
			
									
						
			
						 
		 
				
		
		 
	 
	        
			
	        
			
		
		
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								mister pointy				                
							
 
	
        
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								 Mon Aug 18, 2008 8:39 am
			
			
			
			
			Great job on a first gun! Now that you have the gun working, you should try cleaning it up a bit. Tuck some of those wires away and replace your tape with clamps or zip ties. 
Then, once you get your turret done, you'll have a great piece to call your first cannon.
            
			
									
						
			
						 
		 
				
		
		 
	 
	        
			
		
		
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								starman				                
							
 
	
        
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								 Mon Aug 18, 2008 10:30 am
			
			
			
			
			Also, what was your reasoning for the fan attachment/choke point design in the back?
            
			
									
						
			
						 
		 
				
		
		 
	 
	        
			
		
		
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								psycix				                
							
 
	
        
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								 Mon Aug 18, 2008 3:58 pm
			
			
			
			
			Looks good for a first gun.
But it has some weird aspects, summed up as:
-Propane tank floating around somewhere. (you could possibly position that between the meter and the chamber)
-Meter pipe being very far away from your chamber. (instead of using a tee, you can just tap an hole and screw it directly in there)
-Excessive amount of fittings, weird reduction (and then scaling up again!) in chamber diameter near the back.
-Pink thingy on the barrel. (Not that it is wrong, but it looks weird)
All this is not wrong, its still a great gun. Its just, well, unique in its shape.
            
			
									
						
			
						 
		 
				
		
		 
	 
	        
			
		
		
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								Kennymester				                
							 
	
        
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								 Mon Aug 18, 2008 6:27 pm
			
			
			
			
			Well I can answer some of your questions. Well the back part of it was originally made so a threaded ball valve could be placed on the back. Long story short it didn't work that well. I already had threads there I had to use so I just made it interchangeable with other things. Also under the circumstances where the fan might break I can just make a new holder. I was also thinking in terms of a rocket when picking out the fittings so I though that if it was kind of like a nozzle in going from big to small to big it might give me better compression. I did fix the propane tank and turned it 180 degrees. As far as the battery holder and stuff I want it confined to the back piece so I think I'm going to keep it like it is. I might paint it in the future too, but I like the homemade look of it. I also ordered some parts for my next one as well which is going to be a golf ball gun.
            
			
									
						
			
						 
		 
				
		
		 
	 
	        
			
		
		
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								Radiation				                
							
 
	
        
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								 Tue Aug 19, 2008 12:14 pm
			
			
			
			
			I've never seen any problem with DWV fittings, but it seems to be a pretty ingrained myth on this site that they are not preferable. I personally have used them with great success. extraordinarily nice for a first cannon! Congrats!
            
			
									
						
			
						 
		 
				
		
		 
	 
	        
			
		
		
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								psycix				                
							
 
	
        
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								 Wed Aug 20, 2008 7:59 am
			
			
			
			
			Okay, so now we know the story behind it all.
Good that you turned the propane tank around. I suppose it looks better now.
Any pic of that?