&--Wednesday, October 3, 2007 ; 6:17 PM
EldwinSchrodinger @ Spud cannon
EldwinSchrodinger @ Spud cannon
loving you always ♥
My next coming up project for a spud cannon will be a full stainless steel body encased and build to look just like the American M18 Recoilless Rifle with a combustion chamber in it and mounting a scope to it for attraction. (Image as shown below. )
A scope could be readily purchased in army shops around the island and mounting it would be simple with a little shopping to do in DIY shops like self fix, wal-mart or even home-fix.
I'll start off with planning the design of the body before bringing it to a factory and request them to do the making of it. So it should take no more than 2 weeks for the procedure.
Here's how the back of it would look like when you open the cap to fill the combustion chamber with combustible gas. Now here's the problem. How will the mechanism look like or how am i able to design one which looks exactly the same.
57 mm recoilless rifle
So there are a few reasons why a combustion powered spud will stop firing, most commonly, the residue from your propellant will build up on the contacts of your igniter and foul it enough to prevent it from working. sometimes the chamber can build up too much exhaust gas and not have enough oxygen to light. and sometimes you can build up too much unfired propellant in the chamber and it will displace all the oxygen. there are a few things you can do to keep your spud gun firing...
o clean the inside, especially the firing chamber, if you use ether or alcohol as a propellant this won't be required as often, but using things like spay glue or hairspray as propellant cause major fouling issues. spraying the interior with carb cleaner or brake parts cleaner should do the trick, and let it dry completely before using it again.
o air it out. let it sit with eveything open for a while so that all the built up gasses can circulate out. you can spray it out with compessed air from an air compressor (not "canned air" cleaning type spray, it will displace oxygen and defeat the purpose) or you can vent it by blowing in it. blowing in it is faster than letting it sit, but keep in mind that your breath has a high C02 content and will make venting necessary more frequently than using an air compressor would. i've seen bottled oxygen used to vent a spud gun, but keep in mind that the combustion becomes MUCH stronger if you do this.
o use better propellant. probably the best propellant for you spud gun is ether, this is found at auto stores and is labelled "starting fluid". go easy on it for the first few tries, because it packs a lot more punch than hair spray. using cleaner burning propellant will make keep your spud gun cleaner and more reliable. hair spray or aerosol glues /paints/ etc. generally leave a residue that causes poor performance in the long run. any type of alchohol, ether, or even gasoline (to use a liquid propellant, wet a rag with the propellant and wipe it on the interior of your chamber, then seal the chamber and give it a minute to evaporate) are better to use than hairspray /glue/ paint.
o if you are using an electric igniter, like a barbecue grill igniter or a fabricated static discharge igniter, make sure you experiment a little with the adjustment of it to ensure you are getting the best spark possible. better spark means a hotter and cleaner burn, and will improve not only the short term performance, but will also require less maintenance in the long run.
if you have any other questions you can post them here, or you can ask your local auto mechanic (a potato gun is very similar to a cylinder in your car engine, any mechanic who understands internal combustion thoery will understand potato gun theory as well)
as a final note, use your spud gun responsibly and don't give the stupid liberals more reasons to try and limit our rights to build and bear arms ;)
Labels: Spud Cannon
