4 replies to this topic

[martyn]

I've been making some crackers with the kids using bought snap pulls.
I have looked at one which 'fell apart' and there seem to be two blobs of black and a blob of white. When the strips are pulled, one of the blobs of black passes over the blob of white and then over the other black blob.
To a novice it seems like a combination of safety match technology and possibly flash or something else fast and sensitive.
I'm working Christmas day and I'd like to make a slightly 'special' cracker for my crewmate, something I could personalise in terms of joke gift and noise;)
Does anyone know what I might try using to make a couple of snap pulls for this. I don't have access to phospherous or anything elaborate.
Cheers

[dave]

I've been making some crackers with the kids using bought snap pulls.
I have looked at one which 'fell apart' and there seem to be two blobs of black and a blob of white. When the strips are pulled, one of the blobs of black passes over the blob of white and then over the other black blob.
To a novice it seems like a combination of safety match technology and possibly flash or something else fast and sensitive.
I'm working Christmas day and I'd like to make a slightly 'special' cracker for my crewmate, something I could personalise in terms of joke gift and noise;)
Does anyone know what I might try using to make a couple of snap pulls for this. I don't have access to phospherous or anything elaborate.
Cheers

commercial snaps use a very small amount of silver fulminate......thats the blob of white you can see.

far easier to buy them.........alternatively could you use a couple or more of the pull units from champagne poppers etc tied together ?

dave

[martyn]

...far easier to buy them.........

dave

Cheers Dave. After doing a bit more research I'm inclined to agree with you.
I'll have to think of another way to spice up the day.

Martyn

[exat808]

commercial snaps use a very small amount of silver fulminate......thats the blob of white you can see.

far easier to buy them.........alternatively could you use a couple or more of the pull units from champagne poppers etc tied together ?

dave

just posted this on another thread. Copied this from HSE EIDAS database. Only recorded instance of serious injury from cracker snaps!

An explosion of fulminate of silver occurred on the 31st July 1911 at the toy firework factory of the Diamond Cosaque Company, Limited, Stratford. By this accident a girl received injuries to her face and left hand, and lost the sight of one eye. At the time of the accident she was engaged in making snaps for bonbon crackers.

The terms of the Licence limit the quantity of fulminate of silver to one grain for each person engaged in such manufacture.

One of us investigated the circumstances attending this accident, and it appears probable that a small supply of fulminate of silver had been surreptitiously accumulated for use when the proper supply of one grain ran short. The explosions was probably due to friction or undue force being used while transferring some fulminate of silver from this supply to the proper receptacle. It appears probable that this extra supply was kept in a tin box, which would account for the injuries received by the girl but there was some contradictory evidence on this point.

[martyn]

I have to admit, I didn't realise these involved a primary explosive. I had rather hoped they contained a relatively simple friction sensitive pyrotechnic type composition, obviously still in minute quantities though.