here are plans from anoter site. are they n e good??
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thespeedycicada
- Specialist 4
- Posts: 429
- Joined: Sun Aug 12, 2007 1:28 am
just get rid of the lantern sparker and use a bbq sparker or camera flash and it will be fine.
current projects: co-axial piston valve.Status DONE!
S.P.E.C.S update mk 1 construction begining in febuary all the maths for it are done plans are drawn up and parts are listed.
NEXT project:auto piston valve.
S.P.E.C.S update mk 1 construction begining in febuary all the maths for it are done plans are drawn up and parts are listed.
NEXT project:auto piston valve.
Don't forget a chamber fan, which you should leave running during firing. Performance will suck without it, even if you do use metered propane.
Advancedspuds, while rather outdated in its understanding of spudding technology, is a great place for any beginner to start. I built my first spudgun from a (slightly modified) design that I found on advancedspuds. You may want to increase barrel size so that it meets the optimal 0.8:1 C:B volume ratio.
Advancedspuds, while rather outdated in its understanding of spudding technology, is a great place for any beginner to start. I built my first spudgun from a (slightly modified) design that I found on advancedspuds. You may want to increase barrel size so that it meets the optimal 0.8:1 C:B volume ratio.
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
I mean that the ratio of the chamber volume to the barrel volume should be about 0.8 : 1.
In case you didn't know, the formula for the volume of a cylinder is
(pi x radius^2 x length).
You should be able to use those to figure out your second question.
In case you didn't know, the formula for the volume of a cylinder is
(pi x radius^2 x length).
You should be able to use those to figure out your second question.
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
there is nothing wrong with the lantern lighter, in fact i like lantern lighters because you dont have to worry about setting gaps, but you do have to replace the flint.
"physics, gravity, and law enforcement are the only things that prevent me from operating at my full potential" - not sure, but i like the quote
you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
It will work, but don't expect to reach the power of most of the guns here, to start I would recommend a simple sprinkler valve pneumatic.
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jimmy101
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It will work fine and is an OK first combustion gun.
Don't use the flint sparker. They work OK but it takes one hand to operate. A BBQ piezo sparker is more expensive (~$12) but are more practical and more "gun-like" since they can be easily built into a pistol grip.
It'll be a bit cheaper (and a bit safer) to not use the 4" cleanout adaptor on a 4"-3" reducer to the 3" chamber. Just get a 3" cleanout adaptor and omit the reducer.
The threaded joint for the barrel is not a particulary efficient design. It requires too many parts. Instead of the "bell reducer" just use a 3" coupler, a 3"-1.5" bushing reducer (you might have to do the 3" - 1.5" reduction using more than 1 bushing), a short piece of 1.5" pipe and the 1.5" male thread adaptor. You might get lucky and find a 1.5" male thread - spigot adaptor that'll save you the short peice of 1.5 pipe.
The best way to design and build your first gun is to decide on the chamber and barrel IDs then go to the hardware store and see what fittings they have. You might also want to get the parts for a pistol grip (1" or 3/4" pipe with a T-coupler and three caps) and a pair of screw hose clamps large enough to go around your chamber pipe and the pipe you are using for the pistol grip.
Once you have the fittings, pipe, PVC cleaner/primer and PVC glue then you can decide on the chamber and barrel lengths.
A fan will significantly boost the performance of the gun. The fan can be added later though.
Don't use the flint sparker. They work OK but it takes one hand to operate. A BBQ piezo sparker is more expensive (~$12) but are more practical and more "gun-like" since they can be easily built into a pistol grip.
It'll be a bit cheaper (and a bit safer) to not use the 4" cleanout adaptor on a 4"-3" reducer to the 3" chamber. Just get a 3" cleanout adaptor and omit the reducer.
The threaded joint for the barrel is not a particulary efficient design. It requires too many parts. Instead of the "bell reducer" just use a 3" coupler, a 3"-1.5" bushing reducer (you might have to do the 3" - 1.5" reduction using more than 1 bushing), a short piece of 1.5" pipe and the 1.5" male thread adaptor. You might get lucky and find a 1.5" male thread - spigot adaptor that'll save you the short peice of 1.5 pipe.
The best way to design and build your first gun is to decide on the chamber and barrel IDs then go to the hardware store and see what fittings they have. You might also want to get the parts for a pistol grip (1" or 3/4" pipe with a T-coupler and three caps) and a pair of screw hose clamps large enough to go around your chamber pipe and the pipe you are using for the pistol grip.
Once you have the fittings, pipe, PVC cleaner/primer and PVC glue then you can decide on the chamber and barrel lengths.
A fan will significantly boost the performance of the gun. The fan can be added later though.
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TurboSuper
- Corporal 5
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If it were up to me, I'd say just use a 4" section of pipe for the chamber, and then use a reducer from there. It's a few less fittings, and the larger diameter chamber makes for a shorter gun.
And whatever everyone else said too.
Good luck, buddy
And whatever everyone else said too.
Good luck, buddy
"If at first you dont succeed, then skydiving is not for you" - Darwin Awards
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Hailfire753
- Specialist 3
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- Location: Near Philadelphia, PA
yes, they are good. I've use them for my gun: http://www.spudfiles.com/forums/viewtop ... html#99667
UPDATED MARCH '08
field-legal paintball semi
field-legal paintball semi
I will go ahead and disagree with the majority here... the lantern sparker has worked great on my last combution. go ahead and use it. just make sure that it is easy to get to when you need to change the flint. and as others have said, put a computer fan in the chamber, it really does make a huge difference.
I like to play blackjack. I'm not addicted to gambling, I'm addicted to sitting in a semi-circle.