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A Lesson In Safety! Could have been worse.


TheSidewinder

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OK, folks. This post is for EVERYONE who believes that ordinary Black Powder can't be ignited by friction or pressure.

 

This past weekend we had a *RELATIVELY* small accident at our Guild meeting. A member, who shall remain nameless, was ramming a BP rocket. It exploded, damaging his right hand, when he accidentally used a rammer from his Hybrid Rocket tooling on his BP spindle (or perhaps vice-versa). In any case, the rammer bottomed out and..... kaboom. And while the damage COULD have been a LOT worse, it was certainly bad enough. He was transported to a hospital for cleaning and bandaging. But there was very little they could do right away to fix the damage. The wounds need to drain for a day or two, and the swelling has to go down before it can be really fixed.

 

The following two pictures show the aftermath of what happened. His ring finger had about a 1/2 inch of the tip completely blown off, the tip knuckle bone completely shattered, and the "middle" bone segment thoroughly cracked. The "meat" on that finger was split and mangled down to the lower finger segment. (Then there's a wad of absorbent gauze between his ring finger and his pinky.) On his pinky finger, the meat and muscle was blown open and torn. The hose clamps from the ramming sleeve gave him several bad gouges on his chest but, fortunately, remained whole and didn't embed themselves. It looks like a bad case of road rash, with a couple of 1/2 inch deep gashes. Those caused no damage, really, they're just going to very painful.

 

He will be seeing a reconstructive surgeon today.

 

This man was VERY safety-conscious, but he knows exactly what he did wrong, took full responsibility for his actions, and gave me permission to post these pics as a lesson in what CAN go wrong when you are careless or inattentive.

 

File this information in the corner of your brain, under "Safety". And the next time you engage in our hobby, remember it as an object lesson. This person got off relatively easy. He could have lost fingers completely, could have lost an eye, or could have been *KILLED* if one of those hose clamps had fragmented and a piece of its shrapnel hit him in a vital spot.

 

Safety First!

 

Pic #1:

accident1.jpg

 

Pic #2:

accident2.jpg

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May I ask - where was his hand in relation to the rocket when it exploded? I mean, was it wrapped around the rocket, or was it above it with the mallet, or elsewhere?

 

I don't possess any rocket tooling myself so I'm not very familiar with it - but I always thought it would be worth having a fixture of some kind to hold the rocket for you while ramming.

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+1^

 

Well, ramming is of my list of feasible ways to make rockets as of now. This is the second or third accident I've heard about on this forum alone. I'm welding a press... And making a blast shield.

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Sweet Jesus!! I'm not a church-goer, but this post deserves an exclamation like that. Dang, and I thought I had it bad, getting stitches on my hand from a CATOed rocket. I'm going to rethink my BP rocket ramming.....

P.S. What is a hybrid rocket? I google'd it, and got the usual hybrid rockets that use N2O and a fuel.

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It was wrapped around the rocket. The rocket was in a PVC sleeve, and contained with steel hose clamps. I didn't notice any real damage to the hand holding the hammer. It's probably sturdy enough to support while ramming, but it just feels more comfortable, and easier to hit the rammer square.

 

Hybrid rockets are a new kind of rocket developed by Steve LaDuke. The fuel is a mix of whistle and BP or charcoal. They produce a lot of thrust, and can carry a lot. They are pretty obvious core burners, but the spindle is shorter than standard BP tooling. The cavity inside of the rammer then doesn't have to be as long, which is what caused the problem.

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It was wrapped around the rocket. The rocket was in a PVC sleeve, and contained with steel hose clamps. I didn't notice any real damage to the hand holding the hammer. It's probably sturdy enough to support while ramming, but it just feels more comfortable, and easier to hit the rammer square.

 

Hybrid rockets are a new kind of rocket developed by Steve LaDuke. The fuel is a mix of whistle and BP or charcoal. They produce a lot of thrust, and can carry a lot. They are pretty obvious core burners, but the spindle is shorter than standard BP tooling. The cavity inside of the rammer then doesn't have to be as long, which is what caused the problem.

 

I was standing about 8-10 feet away from this person when it happened. I heard the bang and looked to see him holding his hand, blood already pouring down.

In my opinion, the stainless steel hose clamps caused the damage along with the sleeve.

I picked up one of the hose clamps and it was broken clean in the solid section, not in the worm drive area!!!

 

Another thing about the PVC sleeves, an X-Ray does not identify the PVC, meaning they can't find it if its in you.

 

I have just bought a press today after witnessing this accident this weekend, and I am thinking of other ways to be safer.

I was checking out some gloves the welders at my work wear, very thick rawhide and cover up past the elbow. Could a heavy glove have prevented some of his injuries? Surely couldn't hurt.

 

I hope the reconstruction doctor has good news for him and I hope everyone learns a little from this.

 

Cull

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Sorry to hear that, I guess the tooling was from aluminium or stainless steel ?

Of course, black powder can explode from an impact, and if the shock point is sharped between the two surfaces, there will be much pressure for less force.

 

I also guess that when I'm using wooden tooling the chances are much less. Though I don't ram rockets, but fountains/gerbs. My tooling looks almost the same as a rocket's tooling, but the spindle is much shorter and it's diameter is constant.

 

There is something strange about these rockets... There are much accidents about them. Could be the metal tooling a problem ?

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yeah, I was crusing pyrobin and and I saw the photo and there's a chat on PF, Man, this was only with an 8oz rocket. I am waayy to clam when im ramming rockets, time to throw on some long arm shirts, some welding gloves and a face shield, and deffenitly will be thinking about throwing a press together.

 

Here is another photo: http://www.pyrobin.com/files/100_2570.jpg

 

Im guessing it is fine to show here cause it is already public on pyrobin???

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I've often thought that rocket supports should have a failure mechanism that would release the energy in a less harmful manner. How to do that, I don't know, and my own clamshell supports violate this rule. A machined block of aluminum around the tube, with a core pin and base, and pressed with a metallic ram, creates a charge that is 100% encased by metal. Even a 4 ounce rocket is going to be horrible. I don't know what the answer is.

 

I think pressing, by nature, is much safer than ramming. The sharpness of a hammer blow creates a shock, whereas pressing creates no shock at all. You can press mercury fulminate to a dead state with no harm, but of course you cannot ram or hammer the same compound.

 

This is an excellent safety issue worthy of discussion. I know a lot of guys cannot afford a press, but one can be made with a $15 hydraulic bottle jack and some threaded rod and scrap steel. Or, if it was my own kid making rockets, and he asked me to spring for a $80 press, I'd do it in a heartbeat as being safety-related. So if there are any young guys doing this, tap your parents. They may be a lot more eager to spring for something like a press than you might think.

 

Gloves suck, but I'll bet heavy gloves would help. Eye protection goes without saying, and some sort of plexiglass shield should be a part of the setup too.

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  • 3 weeks later...

Man, I am so sorry this happened to you sir! This is exactly why I

-mark my black powder tools with black tape

-work with black powder in seperate location than everything else

-wear a welders jacket/gloves/apron/face sheild

-and never use pvc

I haven't had any issues (yet! I am a beginner) but this accident makes me wonder. If I were making a fountain by ramming 10 grams of black powder into a 1in by 4in card tube(1/4in walls) and it were to accidently ignite while wearing my safety gear, wouldn't the clay plugs blow (or the dowel blow out) before the card tube ruptured? Could 10 grams of BP in paper do as much damage as this rocket did? I'm using 60-KNO3 (not milled), 30-Charcoal, and 10-Sulfur.

My regards,

Skycastlefish

Edited by Skycastlefish
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Man, I am so sorry this happened to you sir! This is exactly why I

-mark my black powder tools with black tape

-work with black powder in seperate location than everything else

-wear a welders jacket/gloves/apron/face sheild

-and never use pvc

I haven't had any issues (yet! I am a beginner) but this accident makes me wonder. If I were making a fountain by ramming 10 grams of black powder into a 1in by 4in card tube(1/4in walls) and it were to accidently ignite while wearing my safety gear, wouldn't the clay plugs blow (or the dowel blow out) before the card tube ruptured? Could 10 grams of BP in paper do as much damage as this rocket did? I'm using 60-KNO3 (not milled), 30-Charcoal, and 10-Sulfur.

My regards,

Skycastlefish

 

OK, this was caused by WHISTLE mix, not BP. The wrong ram was used, the whistle mix was stuck in the ram spindle hole, the spindle and ram contacted each other and created ignition of the whistle and set off the BP. Like Swede said, using a less forgiving sleeve could have different ramifications all together. PVC sleeves with hose clamps make for pretty good shrapnel but don't have a lot of inertia, solid clamps have tremendous inertia.

 

If the center of a motor goes, it will create a shattering effect and will escape the way of the less resistance. I remember AFN lll (I think) that spoke of one pyro sending a ram through the cieling of his garage when a motor went on the first increment.

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No one knows for sure what was in there, but there are theories. He was making BP rockets, no metal in the fuel. People think he grabbed his hybrid spindle accidentally, and pinched some fuel at the top of the spindle. It very well could have been whistle, or at least hybrid fuel which is mostly whistle.

 

I'll put it out there that I know of another individual who had a purely BP rocket go off on him. No whistle potentially involved. Static electricity is the only cause we could come up with. I wasn't there, and I only have 1 source for this, the unfortunate individual.

 

It's hard to say what would go wrong, but I'd rather you not find out the hard way. Given what you describe, you seem to be taking about every reasonable safety measure possible. A press is about the only thing that could potentially make it safer. If said individual had been wearing the gear you describe, he possibly would have ended up in somewhat better shape.

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Thats not nice , i even rammed lots of bp rockets with Fe in it , so iam making a press now , a small one for just small rockets and a good blasting shield ofcourse :)

Anyway , even people who still go on with ramming , buy some kevlar gloves they alwase help you against some schrapnel , u might never know :)

Greetz.

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The safer the better. I will keep on ramming BP for a while. A press would give me a piece of mind and definitely would be easier on the ears.

 

 

Thats not nice , i even rammed lots of bp rockets with Fe in it , so iam making a press now , a small one for just small rockets and a good blasting shield ofcourse :)

Anyway , even people who still go on with ramming , buy some kevlar gloves they alwase help you against some schrapnel , u might never know :)

Greetz.

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I still haven't made a press, I'm working my way though. But my safety tips for BP ramming are :

 

-Use a rubber mallet, it absorbs some of the shock.

-Don't use tooling made from sparking metals.

-Instead of ramming few times with powerful strokes, ram many times with less force.

-PROTECT your tooling from contamination. I put my black powder tooling in a box.

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Well... a rubber mallet really isn't very efficient. You lose too much energy in the "bounce" when you strike the rammer with it.

 

A rawhide mallet is a better choice, though it may be hard to find and they do wear out relatively quickly.

 

Personally, I use a small (~2 lb) short-handled sledge hammer, but my rammers are Aluminum so I won't be getting any sparks. I certainly don't take a full swing at it, but I do hit it "briskly".

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I use a rubber mallet, and tooling that the local machinist made for me, for FREE :D . Made of aluminium and brass. I have moved off of BP rockets, and now concentrate on Teleflite propellant and RCandy. I find that they are less time-consuming, and for me, give more predictable results. And I get sick of making paulownia charcoal for endburners.
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  • 4 weeks later...

So from what I'm understanding ramming rockets are pretty dangerous(I have a shallow idea of how to make them),

and it' something I should stay away from since I'm a newbie

(I won't touch them nor do I have a desire to make them) ?

I'm the kind of guy who knows I'm safe or does whatever possible to be safe,

if it can't be made,relatively speaking safe I don't do it,

since I don't relish what happened to happen to myself.

 

I'm assuming ramming fountains is different since the chemical composition is slow burning, relatively speaking ?

So if I rammed down too much(metal striking metal an igniting the mixture) in a fountain instead of a rather nasty accident I could have something much less benign ?

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Ramming BP rockets is relatively save, it's just ain't smart to use tooling which is been in contact with whistle or just perchlorate. This is what caused the problem not the blackpowder, the blackpowder just ignited by the spark and/or heat from the reaction of perchlorate and sulfur. Perc and sulfur is sensitive, not as sensitive as sulfur with chlorate, but still a lot more then black powder.

 

The story of the first post is a bad example IMO.

 

About the fountains, I think the fuel has to be fast, most of the time there's a metal in it, so its better to do not ram them.

Edited by FREAKYDUTCHMEN
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"The story of the first post is a bad example IMO."

 

Errr... a bad example of *what*, Freaky? :huh:

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I was ramming a 1lb today and my flat ram pinched the top of the spindle on my core burn, I had ignition and I was quite surprised to say the least. I needed one more spoonful with the short hollow ram obviously! This gave me a big lesson learned. I am fairly new to the hobby and thought I was being safe. This was my first bad experience and I hope the last. I have no other idea why the ignition. I was ramming 6/3/1 bp with no metal
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I was ramming a 1lb today and my flat ram pinched the top of the spindle on my core burn, I had ignition and I was quite surprised to say the least. I needed one more spoonful with the short hollow ram obviously! This gave me a big lesson learned. I am fairly new to the hobby and thought I was being safe. This was my first bad experience and I hope the last. I have no other idea why the ignition. I was ramming 6/3/1 bp with no metal

 

Scary, by 1 ponud do you mean one pound tooling, or the rocket is 1 pound?

also, the point of rocket tooling it that it dosn't spark, why else wouldn't you just use wooden tooling, a hardwood would jold up pretty well. of you could use an AL base, and just use pressed hardwood rammers, just a thought.

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1 lb rocket tooling -3/4 inch tube. It is a bought tooling kit made of aluminum

 

 

Scary, by 1 ponud do you mean one pound tooling, or the rocket is 1 pound?

also, the point of rocket tooling it that it dosn't spark, why else wouldn't you just use wooden tooling, a hardwood would jold up pretty well. of you could use an AL base, and just use pressed hardwood rammers, just a thought.

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