106 replies to this topic

[paul]

Hello everyone!

i will write this text in small letters only as i can not use my left hand very good.

today i had my first accident after about five years with my hobby. i put a 15mm id tube on my rocket spindle. it has an 20mm 6mm rod on it to make the nozzle and 1cm of the core.
the spindle and rammer is completely made of SPARKLESS stainless steel. further on i used a plastic hammer to ram them.

the composition was milled black powder. the charcoal was willow charcoal. it had 10% extra charcoal added.

so i rammed in the clay nozzle [bentonite] and went on with the blackpowder. i rammed it not very hard. suddenly a big flame as i hammered in the second increment. at this time only about 3g bp were in it. the rammer came out the case, not very fast as it went in very losely.

anyway, the rockets flame shot out of the open tube for about 1sec. my left hand, i hold the spindle for stability purposes with it, was burnt on the inside. i have a very huge white vesicle inside my hand and two fingers were burnt near the fingernail.

i had safety glassrs on and a cotton overal. what i had NOT on was GLOVES. this was my first and biggest mistake ever and should warn you to use proper safety gear when making ANYTHING relating rockets.



i wanted to inform you about that because i think the community should know about all accidents that happened to members.

i know that it was definately my fault as i did not wear gloves. i know everyone says in forums like this one, that he ever wears gloves. but i also know from many people that they do not use them all the time!!!

so PLEASE be safe and use them. they are not very comfortable to work with on this small devices. but you "see" what can happen.

i will upload an picture of that. i can still move it and so on. only the burnings burn as hell. went to a friend who is a doctor, too and he cleaned and bndaged it propperly.

with best regards,

paul

[fishy1]

so what made it happen?
did your "sparkless" rammer spark?

[paul]

i think it was a small amount of black powder between the rammer and the spindles rod that caused the ignition. as this would be the only source of too much friction.

i think it was a problem of friction. i never thought about that because bp is a quite stable compound from my experience.

Edited by paul, 03 December 2005 - 02:43 PM.

[Pretty green flames]

so what made it happen?
did your "sparkless" rammer spark?

Enen though the tooling is made from sprakless materials, contact between the rammer and spindle can cause enough heat for the BP to ignite.


Hope you get better soon Paul.

[fishy1]

ok, i see, get well soon paul.

[karlfoxman]

Im glad your ok Paul and im also glad you posted the accident, its a reminder to all of us that our hobby is a dangerous one. Accidents might be remote but they will happen, i hope you make a speedy recovery and are back with pyrotechnics soon. Is it possible the BP/SPINDLE were contaimiated?

Edited by karlfoxman, 03 December 2005 - 04:17 PM.

[Ritual33]

Indeed, the same from me paul, hope it's nothing serious. In light of what I have read about such accidents I wont be ramming any rockets untill I have proper safty material and clothing etc, the only good things that come out of such things happening is that it goes as a warning to everybody else that may think they are safe when doing such thing.

Get well soon mate.

Drew

[chris.h]

It just makes you think, I've just come in from the shed after ramming four 4oz rockets ready for testing tommorrow, and I must admit I wasn't wearing gloves.
Hope it heals soon.

[fishy1]

i haven't made rockets for a while, and i won't make more until i finish my press with a nice piece of blast shield stuff.

[barra69]

Paul, I wish you a speedy recovery and with no long term affects. Thank you also for being so honest and open. Sometimes it is difficult to accept that you have made a mistake, but to be able to share it with the forum is good. It reminds us all of the potential for misfortune when working with a material we become familiar with.

[GBthriller]

i think it was a small amount of black powder between the rammer and the spindles rod that caused the ignition. as this would be the only source of too much friction.

i think it was a problem of friction. i never thought about that because bp is a quite stable compound from my experience.

Thanks for the in-your-face reminder. Many of us are guilty, you paid the price. Being a person that absolutely requires his hands to feed the family, I'm going NOW, TODAY and buy two extra pair of gloves, with different levels of protection vs. mobility to allow no reason for ever being without some protection.

So sorry for the pain. Prayers for you.

While were on the subject, how many of us have the ball mill well enough protected? Do we need someone to tell the story of the lost house, or body part before we move it out of the basement? I admit guilt; its on my chest freezer (garage) right now making air-float pine charcoal. And later it was going to be making D1 glitter, and honestly, I hadnt planned to move it. Now I will.

Thanks again Paul.

[fishy1]

Thanks for the in-your-face reminder. Many of us are guilty, you paid the price. Being a person that absolutely requires his hands to feed the family, I'm going NOW, TODAY and buy two extra pair of gloves, with different levels of protection vs. mobility to allow no reason for ever being without some protection.

So sorry for the pain. Prayers for you.

While were on the subject, how many of us have the ball mill well enough protected? Do we need someone to tell the story of the lost house, or body part before we move it out of the basement? I admit guilt; its on my chest freezer (garage) right now making air-float pine charcoal. And later it was going to be making D1 glitter, and honestly, I hadnt planned to move it. Now I will.

Thanks again Paul.

i only operate my ball mill outside, that's one thing i really am paranoid about, i mean paul only got burn (still bad), but if a ball mill goes up lead balls get shot everywhere, which is even worse.

[Ritual33]

just a thought, most injuries from pyrotechnics are to the hands, sometimes people loosing fingers or worse, would chain mail gloves work as a defence againsed gun powder and flash powder blasts?
p.s i already know about flash and static.

Regards,
Drew

[paul]

someone asked about contamination of the spindle or tools. dont know who it was.

i have never used chlorated or perchlorates with the spindle or at all. i only have about 100h kclo4 left, which i only use for making small amounts of flash as a break-booster.
i never bought chlorate, so ther simply can?t be any contamination.

what comes to my mind ist, that there could have been straw charcoal in the blackpowder! but this was totally carbonized charcoal, not the sensiotive kind which is only carbonized for about 30minutes to leave much volatiles in it.

anyway, i will tkae some photos of the spindle, the casing and my hand tomorrow. atm i don? t feel any pain as i took two paracetamol.

thanks for all your good wishes. it?s great to hear, that some of you took a thought about their manufacture processes and so on.

with best regards,

paul

[Andrew]

The problem with stainless is that it is very hard. No matter how hard you try to make it non-sparking it will still spark under the right conditions. Also, as it is hard, the chance of friction ignition is a lot higher. The most likely cause is probably contamination as Karl said.

Anyway, get better soon.

Someone once said, it does not mater how many mistakes you make, just so long as you do not make the same one twice.