43 replies to this topic

[bigtonyicu]

Then why bother? You learned first hand that it is obviously not a good comp to work with. For safety's sake, I'd toss that comp into the "tried and failed" list.

Well I don't agree that it's not a good comp... it just might be a bad technique or a good technique with unsuitable materials (butcher paper)... if that impact test didn't set it off it's fairly insensitive, it's not a bad combination of chemicals, lots of NO3 flashes use these chemical and are very safe.

It's like using a ball mill to mix a metal + nitrate or chlorate star comp... If it goes off... it doesn't mean it’s a bad comp... It just means the technique wasn't suited to the mix.

[Bonny]

Well I don't agree that it's not a good comp... it just might be a bad technique or a good technique with unsuitable materials (butcher paper)... if that impact test didn't set it off it's fairly insensitive, it's not a bad combination of chemicals, lots of NO3 flashes use these chemical and are very safe.

It's like using a ball mill to mix a metal + nitrate or chlorate star comp... If it goes off... it doesn't mean it’s a bad comp... It just means the technique wasn't suited to the mix.

If diapering a mix is not suitable, then I don't think the comp is by any means a safe one to make... and NO flash powder (NO3 or whatever) is 'very safe'. IMO it's best to err on the side of caution, especially when dealing with flash.

[bigtonyicu]

If diapering a mix is not suitable, then I don't think the comp is by any means a safe one to make... and NO flash powder (NO3 or whatever) is 'very safe'. IMO it's best to err on the side of caution, especially when dealing with flash.

The general concencus seams to be that Butcher paper is bad for mixing flash ALWAYS... fo the comp does not seam to be the isseu but the paper is.

[Arthur Brown]

A friend told me he mixes flash in the ball mill, For clarification that is in a medical sample bottle in cotton wool in the centre of the drum, no media! So the powder just tumbles to an intimate mixture at the end of a very long extension lead to the mill.

[bigtonyicu]

A friend told me he mixes flash in the ball mill, For clarification that is in a medical sample bottle in cotton wool in the centre of the drum, no media! So the powder just tumbles to an intimate mixture at the end of a very long extension lead to the mill.

RUN!!!!... even in High humitity that kind of friction is begging for trouble.

The kind of shock wake generated will shatter the container and his primary container and essentially have a grenade... I hope that his extension in over 100 meters!!!

Edited by bigtonyicu, 03 September 2008 - 09:53 PM.

[wjames]

the word "brave" comes to mind.....

i know everyone is using the work "friction here" -but to clarify ( for myself) its not the friction...its the static charge CAUSED by the friction that could ignite flash ????

[bigtonyicu]

the word "brave" comes to mind.....

i know everyone is using the work "friction here" -but to clarify ( for myself) its not the friction...its the static charge CAUSED by the friction that could ignite flash ????

Thanks James, that is correct

and I'd use stupid not brave.... and I'd love to know the qty he's mixing to need a ball mill... I hope the ball mill is deep inside a hole.... could be the crater left from the first time he did that.

[Arthur Brown]

Tenths of grammes at a time, at 50 metres - I'd rather have a bang that size down the field than in a paper near my hands.

[wjames]

out of interest....

when you guys are making a flash report....or just say for instance, a "m-80"
how on earth do you go about plugging the ends of the tube ???
surely using end caps is a big no no....the slightest amount of flash in between the surfaces...and KABOOM......bye bye fingers.???

[Mortartube]

When I worked in a factory, we plugged our salutes with tapered corks. One drilled with the Bickford delay fuse glued in it, this was put in first with PVA glue.

When that was dry, the flash was put in and another cork glued in the top with the barest minimum of PVA required to do the job. When that was dry the delay fuse was primed with meal A slurry in a gum arabic solution and then the end was dipped in granular BP, like 2FA.

If you fancy using cork, these lovely people supply. I am unsure of minimum quantity.

http://www.ribaprodu...nal/cov.htm?ac=

[knackers]

excuse my forward brashness,, ''BUT'' it seems ( not just in this forum ) there are a lot of pedantic safety experts,, ( a little bit of knowledge is dangerous ),,,.....,, i have been told there are lots of physicists, rocket scientists and chemists on this site but must say i have not seen much evidence to support this..... perhaps just very experienced pyrotechnists masquarading,, ?... if i am wrong then please afore mentioned... SPEAK NOW and voice your expertiese more often in forums!

Big tony.....Glad to hear you were not seriously injured,,,, try kraft or news paper, or the 2 paper cups technique ( no static ) your comp sounds secure, but you never said what the bench you diaper on is made off ?

quote Aurthur.......
Tenths of grammes at a time, at 50 metres - I'd rather have a bang that size down the field than in a paper near my hands.

if you diapered 10ths of a gram and it did go off.... you will not loose your fingers,,,( i am sure you are aware off this ) however they may get a little scorched ,depending on appendage proximity, although i do not mill high energetic compositions, i have a a rubber static free barrel and would be safe tumbling small quantities of flash, ( with no milling medium ), but i wouldn`t for the sole reason ...... i don`t make enough at one time to warrant it,,,

Qoute James............
out of interest....

when you guys are making a flash report....or just say for instance, a "m-80"
how on earth do you go about plugging the ends of the tube ???
surely using end caps is a big no no....the slightest amount of flash in between the surfaces...and KABOOM......bye bye fingers.???

if you are not carefull or competent enough to load a report of any description without soaking the plugging end with flash or whatever composition you may desire, you should not be using it ! or need to excersise greater care in you handling of dangerous materials..

i agree that safety is paramount.... but keep it in perspective,,, when somebody mentions a touchy subject all the safety experts, come from nowhere,,, when diapering a few grams is/ does have its dangers,,, its not life or limb threatening

Edited by phill 63, 06 September 2008 - 06:31 AM.

[pyrotrev]

The "how do you seal the tube up?" problem is another good reason for post-assembly mixing by gentle tumbling I think, though if I was doing it regularly I would make a wire mesh drum to do it in.

[wjames]

wow, what a reply....i was simply asking how others do theirs....

[bigtonyicu]

You never said what the bench you diaper on is made off ?

Grounded stainless steel (as per Canadian code)

(and thanks for agreeing with me that the mix is NOT the problem)

I agree with you that some people are very quick to jump to conclusion with no chemistry back ground

[Bonny]

Grounded stainless steel (as per Canadian code)


I agree with you that some people are very quick to jump to conclusion with no chemistry back ground

I'm curiuos as to which Canadian code you are referring to here.
As for jumping to conclusions as many of us did, your accident demonstrated something was wrong (in this case likely the paper/procedure) as for chemistry backround , that would be of little help here as I don't think there was any chemical reaction that took place UNTIL the comp ignited due to (as everyone seems to suspect) static. Personally if it happened to me, I would simply move on to a different comp, but that's just me. Nobody is trying to jump on you, but only to figure out what happened and to prevent injury.