Author Topic: Thunder Mug Question. (Read 2978 times)

GGaskill · « **Reply #30 on:** June 23, 2012, 05:26:47 PM »

Better late than never, I guess.

I have a machined aluminum thunder mug that purchased, not built. The bore is 2'' by 4''. It is 5'' long and has 1'' walls.

You might consider lining this with a steel liner with a 1" bore and 2" outside diameter. Not so loud but lots safer.

josiah712 · « **Reply #31 on:** June 24, 2012, 01:58:49 AM »

Or I could just keep shooting it like I have been doing for years now. I have loaded it two thirds full on several occasions (no cracks). My standard load is only about twenty percent full. That company has sold hundreds, if not thousands of aluminum mugs. Many of their steel mugs are very thin walled. It only takes one accident and then one law suite and their company would have been out of business. But there they are.

You say it's unsafe. I say it is safe, and legal, and i will be using it like always.

I will give you this; just in case you are right, I will be firing it on the other side of the big tree.

I'm glad that you "engineers" didn't design my 12 gauge pump; because I wouldn't be able to carry the thing.

keith44 · « **Reply #32 on:** June 24, 2012, 03:49:52 AM »

easy there josiah712, read the sticky's and follow the links to those who set the safety standards we just live by them and try to guide others into them to protect the hobby from liberals as well as those who enjoy the hobby.

Just because it has worked for years (or seemed safe) does not make it so. My employer receives rail car deliveries regularly, and for 40+ years had a habit of pushing empties out of the way with a large fork truck (huge fork truck) until one rolled too far and could not be stopped. No one was hurt but several pickup trucks, and special equipment brought in by contractors was damaged or destroyed, and new contractors had to be found to complete the job.

Doc Brown. · « **Reply #33 on:** June 24, 2012, 08:42:35 AM »

　
　
Yield Strength Ultimate Tensile Strength
Stainless steel AISI 302 - Cold-rolled 520 860
[/color]Aluminium alloy 2014-T6 414 483
Aluminium alloy 6063-T6 0 248
[/color]Brass[/url] 200 550
　
[/color]Spider silk[/url] 1000
[/color]Cast iron[/url] 4.5% C, ASTM A-48 130 200

Human skin

15

20

Based on this Scientific research I just did from my engineering station some aluminum should be way better than Cast Iron. Even knowing this I would not buy an aluminum cannon. Its been burnt into my brain that it would be dangerous. I would imagine that the fireworks people might use this type of stuff though.

josiah712 · « **Reply #34 on:** June 24, 2012, 08:55:55 AM »

I'm surprised that brass has so much strength advantage over cast iron.

Doc Brown. · « **Reply #35 on:** June 24, 2012, 09:01:50 AM »

Quote from: josiah712 on June 24, 2012, 08:55:55 AM

I'm surprised that brass has so much strength advantage over cast iron.

There are many grades of brass. Some brass is very very strong. Naval Brass rivals most all common steel types used in cannons. My data was just a quick wiki table of different steels. Also Im sure the type of cast iron in cannons exceeds this measurement or at least I hope so because it would mean cast iron is very weak or everyone is over engineering cannons.

josiah712 · « **Reply #36 on:** June 24, 2012, 11:19:04 AM »

Anyone can prove for a fact, they are over engineering these cannons; that's why I compared it with a shotgun.

What is the operating pressure on 12 gauge magnum shotgun? Look at the chamber walls. How thick does high carbon steel need to be, to safely contain this pressure.

How much pressure can a two inch black powder gun generate; with projectile and without?

How much cast iron, aircraft aluminum, cannon brass, tool steel, or even pvc would it take to safely and consistently contain this much pressure. I say way less than a one inch wall for a one inch bore, in tool steel. I implore you; think about this.

In the 1960s Fess Parker series "Daniel Boon"; they made a cannon from a hollowed out pine log with steel belts around it. And it held!

In the 1960s Johnny Horton song "The Battle of New Orleans"; they made a cannon out of an alligator. The gator did lose his mind. But other than that they had a fully functioning cannon. Albeit, maybe only one shot per gator.

If you want to convice me that these cannons are not over engineered; then you will have to have more evidence than just a dozen hobbiest cannoneers that agree that they aren't. Scary stories won't cut either. The gun industry uses proof testing and mathematical fact. Where's yours.

Zulu · « **Reply #37 on:** June 24, 2012, 11:35:32 AM »

josiah,
You sound supisiously like Ramrod.
Zulu

josiah712 · « **Reply #38 on:** June 24, 2012, 11:48:02 AM »

No sir, I'm not Ramrod. Nor do I know of him.

If you look at my post history, you will see that I have been registered for a long time, but just starting really posting on GBO.

I am not trying to be difficult, or disrespectful to anyone here. But when I don't agree with something, I am usually able to explain why.

Is Ramrod someone who was banned from this forum?

Doc Brown. · « **Reply #39 on:** June 24, 2012, 11:52:39 AM »

I think that the main concern with wall thickness and steel types is not as black and white as it would seem.

BoomLover · « **Reply #40 on:** June 24, 2012, 12:31:25 PM »

Doc, not to mention the combined knowledge of the forum members, along with hundreds of years of cannon building (and blowing up!) to arrive at the safe limits we are willing to adher to. To us, it's all about safety, and not wanting to see anybody's name in the paper following an unfortunate accident.
Josiah712, don't think anyone is trying to personally attack you, but why not instead of saying "Show me your "proof", or I'll go on and do it my way", ask for some of the many examples of cannon failures which have been featured here for quite some time. Read some of the back posts regarding this issue, and try to see why we stress overbuilding and safety so much. Some of these guys have experienced cannon failures first hand, and those were made of stronger stuff than yours...
BoomLover

BoomLover · « **Reply #41 on:** June 24, 2012, 12:37:04 PM »

And by the way, because of this forum, I have cut up and discarded more than one "cannon" I built because after reading the safety and strength considerations, I agreed that what I had was an "open-ended bomb" waiting to blow up in someone's face, and didn't want it to be me or anyone else I knew....

josiah712 · « **Reply #42 on:** June 24, 2012, 12:39:52 PM »

Fair enough, from both of you.

I am interested in failures from salute/signal cannons, with no projectile, using Goex Cannon or equivalent. What happened, and what is believed to be the cause?

Give me a link, and I'll read it.

Doc Brown. · « **Reply #43 on:** June 24, 2012, 01:09:15 PM »

http://artillerymanmagazine.com/accidents.html Lots of accidents here. .

josiah712 · « **Reply #44 on:** June 24, 2012, 01:37:00 PM »

Ah common Doc, you gotta be kiddin me. You can see what happened here right from the start. These really are "hold my beer", redneck moments. I know, I'm a redneck too, and as Jeff Foxworthy calls them "my people". A BB bore down a forging the size of a car, can't stop stupid.

Show me what I ask you for. And don't forget; early cannons were made of cast iron. Even the big ones, with solid lead balls. Sometimes cast with very poor pot metal, whatever they had. The difference: Black powder only, no idiots putting subs or junk in there. Look at the cannons they were building in Richmond during the war.

Cannons are failing now because of stupid stunts, and this ridiculous over engineering is the same solution that liberals and lawyers are always using.

Doc Brown. · « **Reply #45 on:** June 24, 2012, 02:18:34 PM »

Quote from: josiah712 on June 24, 2012, 01:37:00 PM

Ah common Doc, you gotta be kiddin me. You can see what happened here right from the start. These really are "hold my beer", redneck moments. I know, I'm a redneck too, and as Jeff Foxworthy calls them "my people". A BB bore down a forging the size of a car, can't stop stupid.

Show me what I ask you for. And don't forget; early cannons were made of cast iron. Even the big ones, with solid lead balls. Sometimes cast with very poor pot metal, whatever they had. The difference: Black powder only, no idiots putting subs or junk in there. Look at the cannons they were building in Richmond during the war.

Cannons are failing now because of stupid stunts, and this ridiculous over engineering is the same solution that liberals and lawyers are always using.

Is this Tim? or is this Skeeter

flagman1776 · « **Reply #46 on:** June 24, 2012, 02:25:36 PM »

Cannon balls were generally iron.

josiah712 · « **Reply #47 on:** June 24, 2012, 02:39:11 PM »

Yes, Yes, true, true, I concede that point.

Now let's get back to the numbers. We're not using pot metal now; we know what we have.

I know you know how to measure; you put up the Wikipedia metal chart. The industry standards for a muzzle loader will easily work on a BP cannon and you know it. You simply cannot justify one inch walls on a one inch bore on a signal cannon. Lawyers or not.

josiah712 · « **Reply #48 on:** June 24, 2012, 02:48:44 PM »

Sorry, Flagman, I thought I was still writing to Doc.

And no again. I'm not Skeeter, or Tim, or Ramrod.

What, did you used to have some thinkers on this board?

What did you do, bore-em to death? Why not two inch walls on a one inch bore? Since you're just making it up, then more would be better, right?

GGaskill · « **Reply #49 on:** June 24, 2012, 06:03:51 PM »

I guess you haven't read the preamble on the Safe Loads and Construction sticky. You should; it will give you some idea where our recommendations come from and why we don't like people challenging them. Pay special attention to the first six paragraphs, especially number four and number six. We are not here to raise each others' blood pressure.

I also see you have heard from the boss; I would take his recommendations to heart if you want to continue to post on this forum.

Now let's get back to the numbers.

Let's get to the basic question here. Give me some documented pressure values for the various small bore artillery that we build here. This is the problem of designing by the numbers. We don't have many credible pressure values and none to my knowledge for guns under 3" bore. Without that information, you cannot tell me that any given design is safe by calculation.

keith44 · « **Reply #50 on:** June 24, 2012, 06:52:12 PM »

Quote from: josiah712 on June 24, 2012, 11:19:04 AM

Anyone can prove for a fact, they are over engineering these cannons; that's why I compared it with a shotgun.

What is the operating pressure on 12 gauge magnum shotgun? Look at the chamber walls. How thick does high carbon steel need to be, to safely contain this pressure.

How much pressure can a two inch black powder gun generate; with projectile and without?

How much cast iron, aircraft aluminum, cannon brass, tool steel, or even pvc would it take to safely and consistently contain this much pressure. I say way less than a one inch wall for a one inch bore, in tool steel. I implore you; think about this.

In the 1960s Fess Parker series "Daniel Boon"; they made a cannon from a hollowed out pine log with steel belts around it. And it held!

In the 1960s Johnny Horton song "The Battle of New Orleans"; they made a cannon out of an alligator. The gator did lose his mind. But other than that they had a fully functioning cannon. Albeit, maybe only one shot per gator.

If you want to convice me that these cannons are not over engineered; then you will have to have more evidence than just a dozen hobbiest cannoneers that agree that they aren't. Scary stories won't cut either. The gun industry uses proof testing and mathematical fact. Where's yours.

The standards are set by governing bodies who are liable for participants and spectators of cannon shooting events. To be allowed to play you either build to their standards, or go home.

12 ga 3 1/2" SAAMI standard is 14,000 psi considering even the venerable 45-70 loaded with original black powder service loads generates 20,000 psi it should be easy to see how a cannon can generate much higher pressures, and should be built to withstand not only sane loads but loads that are well into the stupid range. With black powder the short seating of a projectile weighing 240 grains over 90 grains of 2F has bulged many rifle barrels.

shotgun pressure data:
http://randywakeman.com/shotgun_pressures.htm

one example of a BP substitute and a short seated bullet. This was a Savage muzzleloader, proof tested to operate at 60,000 psi

http://www.thefirearmblog.com/blog/2012/04/17/muzzleloader-kaboom/#comments

josiah712 · « **Reply #51 on:** June 25, 2012, 12:02:42 AM »

Yes, I have heard from the boss. I can't discuss this any further.

keith44 · « **Reply #52 on:** June 25, 2012, 04:58:56 AM »

understood