Out of interest whats the stance on greasing.oiling the barrel? Is this a done thing or does it just get sticky and make the situation worse, or catch fire? Just load an oily rag in there and drop it out of the bottom or something That's much debated. Some people will say that some types of oil can...

@Hotwired: Damn, why can't I find a place like that near me?

My mostly complete designs (they just need dimensioning) are fairly standard machining - I could do it myself with a half day in a machine shop.
The problem is I don't know what standard costs are like.

@couchquail: I started writing that post after the first post by cajuncannon, so it didn't take into account the posts after that one. I was in and out of the room cooking dinner, so it took a little while to write. So, it is out of place for when it was posted, but not so much when it was written. ...

I disagree, you can buy a decent sized length of 10 bar rated pvc (110mm, 90mm,75mm...) for quite a reasonable price from hendersons or if you look into it you can probably find it cheaper. Yes, but not everyone is fortunate enough to live near a Hendersons. The word "Downpipe" is not usually an in...

Couchquail, though I very much agree with some of your points, Killjoy didn't cross any legal boundary I can think of with that. It was a harsh comment on the quality of the launchers, but it wasn't a death threat, or expressing a wish of death. ...Unless setting up a fund for advancing spudguns is ...

I'm going to echo that comment - between all online spudders, we've seen everything and anything spudgun. (well, except a few things, but we're working on those.) I can see _Fnord's already done it, but I'll break it down as well. Complete inaccuracies in red , dangerous assumptions in orange , ques...

I thought I had both of those attributes. There must be an unseen X factor.

Energy is the weirdest of things. It hurts to think about it too much.

But, if you should happen to find SCH 40 Damascus steel * pipe then you can take it as read that it's tough. * A legendarily strong steel used for making swords between the 12th and 18th centuries, recently discovered to contain carbon nanotube structures created by the complex production process Th...

It sounds like we probably have a UK user here, which may mean that the pipe is unrated. Rated PVC is rarer than hen's teeth in the UK. The cannon exploding is improbable, as long as the friction in the barrel is less than the strength of the walls. Still, I would recommend building a cannon from pr...

@psycix: Sounds exactly like that to me. Can I also add: - A suspicious knowledge of the construction, and part names. And theories for why they are used. - The fact that he knows that the endcaps have SCH 40 printed on them, despite the fact that the pictures on the site clearly show the Twister pa...

@Markfh11q: That density change would require chilling to -127^oC (-169 ^oF), which is also well below the melting point of propane. To get that cold, I hope you've got lots of liquid nitrogen handy, and then some way of breaking the 2nd law of thermodynamics to keep the propane ...

Paint? God-damn, that must have taken ages.

Hmm, I didn't think of that.

Do you have a link to this cannon of yours?

I'll admit to having wrecked a few things while not paying attention, including a finger, thumb, and a palm. However, unlike launcher parts, they repair themselves (in no small part due to my mutant healing abilities of course) Other than body parts, I've turned a few things into junk by accident: -...

Interesting. It'll certainly work, but exactly how much extra power you'll get will be an unknown, at least until you test it. You could estimate with GGDT, but GGDT wasn't designed for quite that arrangement. Of course, you could pilot the 2nd QEV with a 3rd as well, but that would be getting stupi...