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A place to ask general spud cannon related questions.
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What do you think?

It will work
1
33%
It won't
1
33%
It will add a little strength but not enough for 10x
1
33%
 
Total votes : 3
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Unread postAuthor: pat123 » Sat Apr 19, 2008 3:40 pm

Do you know of any other way of strengthening it without buying new parts?
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Unread postAuthor: pat123 » Sat Apr 19, 2008 4:24 pm

I just did some research on mcmaster and I could get new parts for $55. every fitting is rated for 3000psi and all of the pipe would be sch 160.
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Unread postAuthor: LikimysCrotchus5 » Sat Apr 19, 2008 8:01 pm

That interests me :)

What kind of pipe? black? can you give me some product numbers?
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Unread postAuthor: pat123 » Sat Apr 19, 2008 10:11 pm

1" tee= 7739k136 = $12.91
that is the only one i wrote down
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Unread postAuthor: DYI » Sun Apr 20, 2008 8:57 am

Umm... The theoretical burst pressure of 2" SCH 40 welded steel pipe is actually about 2300 psi. SB15's original calculation was wrong.

I wouldn't trust 150 psi malleable iron fittings at 10x unless I was quite a distance away from it. Absolutely not in a handheld. I'm going to try my Hybrid1 at 10x, but I'll be 50 feet away behind a very large rock.

And my concrete method is absolutely useless. It has no shock resistance whatsoever, and it'll shatter if you drop it. In my opinion, the most affordable method for strengthening pipe is a fiberglass casting around it, and even that isn't exactly cheap, as resin's about $20/L.

I recommend that you just get some proper fittings for Biohazard. I use the iron one's at 500 psi in handhelds, but that's only half the pressure of 10x combustion, and is a static load rather than a shock load.
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Unread postAuthor: bigbob12345 » Sun Apr 20, 2008 9:04 am

_Fnord wrote:
sch40 steel pipe is already fine for 10x.


Stop saying that!
Ok, so it might have worked fine for you, and I tested it at that mix, but you can't pretend to know all the variables in someone else's gun.

The fact is, 10x is running very close to the theoretical burst pressure of 2" threaded sch40, which doesn't make it fine until you can prove there are still decent safety margins.
If you have a blast shield of some sort, then it should be acceptable to use such mixes. If you just "stand back a little", it probably isn't wise.



I thought I said not to quote me :wink:

but as DIY said 2in threaded sch40 bursts at around 2000psi and lower diameters would burst at an even higher pressures.
Its the fittings that burst at that pressure

But please when I say Do Not Quote Me I am asking you not to quote me.
Because I knew there would be many objections to that.
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Unread postAuthor: Fnord » Sun Apr 20, 2008 9:40 am

I thought I said not to quote me


Ha! I'm doing it again!

(Sorry, I missed that the first time somehow. )

2" welded steel should be around 2300, but this is threaded pipe. Threads typically cut the pipe thickness in half, therefore creating a weak point which should not be ignored. It's always safest to use the worst possible scenario when calculating burst pressure.
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