Old Technology - Blue Touchpaper

Old technology is often embraced purely on the basis of nostalgia, I prefer to see it preserved on the basis that it may hold a value that could be employed in the future.

Recently asked to replicate blue touchpaper as it's burning characteristics were specifically needed in a contemporary device. We did oblige the client and it was a pleasure doing so. Researched the subject and this threw up some very interesting and satisfying stuff. There were three companies producing this in the "glory days", none interested now but one company only recently disposed of the equipment. The story that emerged was that the process was refined by a German chap before the second world war, machinery was developed and put into service, the german worked like mad to make it happen and as the anticipated announcement of hostilities drew ever closer he worked harder and harder to get the job up and running. He was given notice to leave the U.K. as he was considered an "alien" and managed - but only just - to sort the job out for the companu (in the midlands) before disappearing presumably to fight us!!!

I found this a charming story and incredibly sad at the same.

 

Any chance that you could give details on the process?
What type of paper was used, nitrate solution concentration etc?

 

Very fascinating and interesting stuff, often wondered how the blue touch paper was produced.

 

I tried to get some blue paper like touch paper to make some dummies but there was little even close that I could find.

 

I've got a big sheet of original blue touch paper, I've put some onto a length of quick match and lit it, it's quite unpredictable stuff

 

I have several sheets in the store. But can find nothing quite like it as inert material. I understand that it was discontinued because the requirements for Cat 2 and 3 timing couldn't be met with it.

 

yes, I believe so. I know WH Smiths used to sell sheets of blue sugar paper..... maybe they still do?

 

I have tried sugar paper - it is too thick and tears when it is twisted.
I read somewhere (Brocks or similar) that it was "cartridge" paper. But I am sure there will be different types and grades?

 

"The Art Of Pyrotechny" 1828, states

However, "Double Crown" seems to be the size of the paper, not the type of paper.

 

I never established the specification for the paper, GSM etc. We had a request to make some and obliged a few years back. Ended up producing around 300,000 small cut squares, my wife did the job with me over a six week period in the run-up to Christmas - she hated it and never failed to remind me! I used a low grade paper similar to newsprint and we soaked the sheets in a solution of water based permament dye/Potassium Nitrate. The sheets were hung to dry overnight in a workshop which was warmed and had the benefit of gentle fans and de-humidification. It was archaic but it worked although crystal formation made the end product a bit sparky in places which was not really conducive to the proposed application of the product. I had a PM from a contributor correctly pointing out that Lead Nitrate was said to be included in the soaking solution, I never knew for certain but was told this years later - it was supposedly used to counter crystal formation but I never got that confirmed. I was told this by John Park, now sadly now longer with us (you will find news of his death in the archive posts in this forum). Standard took to making their own before the end using an automated rolling, coating and drying machine, I was going to buy it but it was too expensive and I didn't need it, I think it was sold for making self adhesive papers in the end, they had a considerable stock of the blue paper and again I was going to buy it but didn't, it was binned in the end. My experience of the material - commercially - shows that these old processes have a tendency to come back years later, losing technology like this - daft as it may seem - is really not at all sensible. I might have a few bits left if anyone wants to pm me, I'll send them out. They're not really up to replicating old fireworks, you would tell the difference but they worked for what I (and my client) wanted.

 

Thank you Spectrum for the feedback.
This is from "Endless Amusement - A Collection of nearly 400 Entertaining Experiments" to make touch paper

Maybe that gets rid of the sparky bits in the end product?

 

The sparks in my case were due to irregular drying and consequential crystal deposits - at the edges and where the solution formed in droplets etc. I presume the crystalline structure of Lead Nitrate differs from Potassium and that way the problem was overcome. Our production process involved hanging wet sheets on cord lines and allowing them to dry overnight then changing for the "day shift", the finish at the base of the sheet was different to that at the top, variations in drying also had an effect, i.e. those sheets closer to the dehumidifier.
When BS7114 was introduced it sounded the death knell for touchpaper. Variations in burn times meant that the performance specifications could not be achieved. I know Standard used to spray Saltpetre solution over trays of upright fireworks to speed up the burn rate when they had a slow batch. The irony was that the industry - or rather certain elected representatives - assisted in the drafting of the Standards and set out objectives that couldn't be reached. When this was recognised at Astra it was panic stations! Sadly the advisers did not include hands-on people who would have known about the problem!

 

I remember each year at our neighborhood 60's bonfire in the cobbled back street of my home town of Bolton, there always used to one or two 'duds' which wouldn't light and would be scooped up with a shovel and dunked into a bucket of water.
I've often wondered about this over the years. Especially while my son was growing up in the 80's - because there never seemed to be the same level of problems with the COSMIC range ( or, was it just I remembered the fear and trepidation as someone's dad approached a dud Roman Candle or an Air Bomb).
The fireworks had been carefully stored in tins and were dry.
So, what would be the general cause of a firework failing to light?
I've often wondered if it was the BLUE TOUCH PAPER which burnt away before the contents ignited.... was it not as efficient as the modern fuse system?
Or - was the firework perhaps somehow wrongly packed with powder inside?
I could NEVER understand why they didn't light?

 

One thing I have noticed which makes a massive difference, is the closeness of the touch paper to the powder. When fireworks are moved and transported around, sometimes they can lose some of the composition. Enough lost in transit can be significant and creates a big enough gap for failed ignition.

A combat to this and a general kickstarter, was the use of a hard resin type composition, stuck in between the folds of the touch paper. This would ignite rapidly after the paper was lit and in doing so would create enough heat and flame to set the main firework composition off. On occasion this was dislodged or not even added, meaning it was harder to start the main reaction using nitrated paper alone.
I should also note, that the resin held the paper in place much more firmly preventing so much escaped powder.

This is one reason....but not the only deciding factor of course.

Regards,
Chris

 

incorporation of lead nitrate or acetate may be for the same reason it is used in the preparation of "slow match"
used in old style muskets to ignite the b.p.
ie. as a burn rate regulator
for the slow match it is claimed it makes it burn slower and hotter

see the web page below
http://www.musketeer.ch/blackpowder/lunte.html

 

The tricky subject of "what paper"...the closest I've located - after many years of keeping an eye out is - wait for it - the 50gsm brown "void fill" paper which the likes of Amazon use in their packaging boxes. It's the correct weight, translucence ( hold up some touchpaper to a bright light...), and various mechanical and similar characteristics. I'll experiment with some "Rit" ( brandname ) dye and see what transpires. All good fun...Kindest regards, J. p.s. you can buy said paper from ebay and similar., thou' you may end up with enough to cover the UK...better keep an eye out for an Amazon delivery

 

A common school science demo that is still done today is to make a kind of touchpaper. We use a sodium or potassium nitrate solution to soak the paper in or draw shapes/letters with. Once dried it burns slowly like the old blue touchpaper. http://www.creative-chemistry.org.uk/activities/firewriting.htm

 

Practicus says 11lb to 13lb blue double crown paper and nothing heavier than 13lb In todays terms this equates to 26 gsm to 31gsm approx. 1 oz nitre to 1pint water. However the nearest to this is tissue paper today and the colour runs and it tears. It's easy to specify colour and weight but there is more to paper than that alone, what about quality and texture?

Not strictly authentic but crepe paper seems to work well. When I tried it the colour did not run nor did the paper tear when wet and when dry it twisted nicely at the mouth of the tube without tearing.

Rod

 

We made it commercially a few years back and used newsprint grade paper. I bought roll ends from a newspaper printing group, coloured the solution with clothes dye and the rest was proper cottage industry stuff. If you filmed it you would have to do so in black and white! Nonetheless I supplied thousands of sheets, nearly hundreds of thousands in fact - never was going to retire off that job!

Ironically, brought the subject up during discussions in Berlin on CE marking with the various appointed "experts", every member laughed off the notion of "touchpaper" - one asked with a straight face - "so if you touch it, it takes fire?"

The result was that they refused to include touchpaper as a recognised material in fusing pyrotechnics or fireworks because in Germany, France, Belgium etc. etc. they weren't familiar with it. Frustrating when "democracy" doesn't work isn't it?

The sad point was that having supplied substantial quantities to a customer in the UK (respected and highly professional end user too) there WAS a demonstrable need for it but the bureaucracy of EU / UN didn't accommodate that in their quest to make for a better world.....I'm not bitter btw, I had completed my obligations and had been paid, I was and am simply concerned that another British development - touchpaper seems to be very British - was formally destined for the dust-bin.

I never made it again but have some stocks left.

In the old days, there were at least three major suppliers in the UK, one in Staffordshire and one in London, to refer to my original post, the one in Staffs was developed before the war by a German chap. He worked his socks off to get it working AFTER he had been given notice to leave Britain on the approach of hostilities but hung on and on to get the process right for his British employers. He just got it cracked and then went back home to enlist and fight us. The irony is that there would be no fireworks made throughout the war years and that touchpaper would only be used in certain munitions until peace had been declared. The story to me is poignant and sad. I feel we all have something in common here with the German chap who, in a very short time, became our enemy! I would love to have had the chance to shake his hand and I bet I'm not the only one.

 

Blue touch paper is available to purchase from Essex Pyrotechnics (for professionals). I wonder if it is old stock or from your batch @spectrum!