Pyrogeezer Posted January 6 Posted January 6 I thought this would be an interesting picture for some members who are interested in Visco type fuse production. Attached is a close up of just spun 1/8" American made Visco type Safety Fuse. This is the commercial grade used by pyros and hobbyists. As can be seen, it consists of 2 winds of cotton thread (12 inner and 5 outer) encasing the black powder core. All weaving is done under constant tension in order to maintain proper diameter and to prevent powder from escaping from between the threads prior to the coating process. It is then coated 2X with a proprietary, specially manufactured Fuse Dope (Nitrocellulose type lacquer) and then dried and put up on 10,000 foot rolls for commerce.
Zumber Posted January 7 Posted January 7 Thats fantastic and really informative....!!! Do you have any information regarding Old traditional japnese hand made time fuse? I have read that damped black powder is pasted over both sides of japnese paper and paper is dried then it is cutted into strips and black powder is spreaded uniformly over it and using bamboo stick placed at edge and rolled ,next same size kozo paper is rolled over it and tightened by hand rolling. Next bamboo stick is removed & kozo paper acts as a cover for core. Then on work table rolling operation is done 100 times to tighten fuse. In our place we do not have permit to use time fuse we are relying just on spolette. Is there any video of full information on handmade time fuse.? 1
Pyrogeezer Posted January 7 Author Posted January 7 I was in Japan many years ago visiting a couple of manufactures and I do remember at one company seeing a group of men and women making the time fuse. Myself and a few compatriots were on a tour and I didn't get to see to many of the details. Now that you bring it up I do remember that the Kozo paper was lightly sprayed with a solution of rice starch before spreading on the powder then dried. Most likely to give the tube a little more rigidity. If I remember correctly the empty cores were formed into a bundle much like their old method of loading firecrackers, covered with the time powder completely then dropped several times to start to consolidate the powder, then rolled over and over again like you said. This was back in the early 80s. I'm sorry I don't know of any Vids on the subject but I would imagine each company had their own system of manufacture.
TXpyro Posted January 8 Posted January 8 Can you show us a photo of the machine that makes the fuse? Only if it's not too confidential
Pyrogeezer Posted January 8 Author Posted January 8 Hi TXpyro, I can show you a pic. of an early version of the Fuse machines, the latest machines are confidential that I have signed an NDA with the company I am working with. The newer machines are much more electronically controlled and of much higher speed and output, (appx. 900 ft/hr each). Unlike most fuse machines that you see on line, these have 3 string bobbin stations that can be used independently of each other including the direction and speed of rotation depending on what type and diameter fuse is required. Also there are several different elements used in the production of the different products to control the burn rate and coating penetration of the powder core, copper thermal wire, tensioners, isolation ribbon fiber and a complete coating system depending on the products final purpose. These machines were capable of producing 3/32" dia. commercial Visco type safety fuse right up to 3/8" blasting fuse.
Zumber Posted January 9 Posted January 9 On 1/8/2024 at 12:44 AM, Pyrogeezer said: I was in Japan many years ago visiting a couple of manufactures and I do remember at one company seeing a group of men and women making the time fuse. Myself and a few compatriots were on a tour and I didn't get to see to many of the details. Now that you bring it up I do remember that the Kozo paper was lightly sprayed with a solution of rice starch before spreading on the powder then dried. Most likely to give the tube a little more rigidity. If I remember correctly the empty cores were formed into a bundle much like their old method of loading firecrackers, covered with the time powder completely then dropped several times to start to consolidate the powder, then rolled over and over again like you said. This was back in the early 80s. I'm sorry I don't know of any Vids on the subject but I would imagine each company had their own system of manufacture. Thank a lot for your experienced response. Your experience is helping a lot to all of us.
Zumber Posted January 9 Posted January 9 47 minutes ago, Pyrogeezer said: Thanks Zumber Any way I can help if I can! This is normal fuse Is this same way that old japnese handmade fuse used to make.? It only showed for core.
Pyrogeezer Posted January 9 Author Posted January 9 Zumber, This is a good representation of how the Chinese made their small firecracker fuse way back when, before they had the machines to produce it today. The only difference that I can see is that the Chinese women used thin hollow bamboo tubes to hold the powder and then spread it out along the center of the damp rice paper. They would take very young bamboo shoots and hollow them out with a metal wire rod to clean out the internal fibers and smooth out the inside hole. I’m not sure if the Japanese used the same method. The Japanese time fuse that I saw was of a larger internal diameter.
TXpyro Posted January 9 Posted January 9 Pyrogeezer, I wonder if someone could develop a machine that could roll this style of Chinese fuse. I know there's a shortage of 2mm visco fuse and it would make a great alternative.
Pyrogeezer Posted January 9 Author Posted January 9 Hi TXpyro: We have been asked numerous times if we could manufacture the 2mm firecracker fuse. It’s difficult to get and most likely only made in China. In order to produce it there are several challenges to overcome. When you get down to that small diameter the powder needs to be extremely fine and treated with graphite for flow characteristics. Something like corning mill dust or BP that has just come out of a ball mill. This is really difficult to work with. The machine to produce it needs to operate at a much slower speed than the normal size Visco machines. There also needs to be a very thin paper ribbon woven in between the cotton fabric and the powder core in order to prevent the NC lacquer from penetrating the powder. This is easy to do on a larger diameter fuse but very tedious on the small diameter fuse, "constant observation". An operator can only run 1 or maybe 2 machines at once vs. 6 or 8 machines making the larger fuse. The bottom line is the COM (cost of manufacture). After crunching the numbers, the fact is, as of now, it isn’t worth the effort financially.
Zumber Posted January 9 Posted January 9 1 hour ago, Pyrogeezer said: Zumber, This is a good representation of how the Chinese made their small firecracker fuse way back when, before they had the machines to produce it today. The only difference that I can see is that the Chinese women used thin hollow bamboo tubes to hold the powder and then spread it out along the center of the damp rice paper. They would take very young bamboo shoots and hollow them out with a metal wire rod to clean out the internal fibers and smooth out the inside hole. I’m not sure if the Japanese used the same method. The Japanese time fuse that I saw was of a larger internal diameter. It means bamboo tubes to be used as a powder applicator? Thanks a lot again...!!😊 1
Pyrogeezer Posted January 10 Author Posted January 10 7 hours ago, Zumber said: It means bamboo tubes to be used as a powder applicator? Thanks a lot again...!!😊 No problem Zumber, Yes, they used the bamboo tube to dispense the powder onto the paper and then roll it up. with a touch of rise paste.
countryboy7978 Posted January 14 Posted January 14 I hope that the quality of this fuse goes back to how it was several years back. The last few orders of American visco I've bought had very spotty lacquer coverage and were not stiff and rigid. Ive heard that some are not even waterproof anymore. The previous stuff had a nice shine and was a pleasure to work with.
Pyrogeezer Posted January 14 Author Posted January 14 Hi countryboy7978, I can assure you all is normal with the American visco fuse. It is heavily coated with 2 coats of lacquer, rigid and shiny.
cmjlab Posted January 15 Posted January 15 (edited) I got a batch of red Visco Fuse (I don't recall where, but within last year or two), but it was more shiny than usual, and the flame front would sometimes outpace the fuse itself by burning the lacquer coating all the way to what I was lighting. The newer batches I've got still ignite the Visco lacquer coating, but burns out in an inch or so, allowing the fuse to catch up and work as intended. Have you seen much of that? Edited January 15 by cmjlab
Richtee Posted January 15 Posted January 15 7 hours ago, cmjlab said: I got a batch of red Visco Fuse (I don't recall where, but within last year or two), but it was more shiny than usual, and the flame front would sometimes outpace the fuse itself by burning the lacquer coating all the way to what I was lighting. The newer batches I've got still ignite the Visco lacquer coating, but burns out in an inch or so, allowing the fuse to catch up and work as intended. Have you seen much of that? I noticed the lacquer burn thing on a batch of red too... very disconcerting to say the least...
Pyrogeezer Posted January 15 Author Posted January 15 (edited) I know about a year or two ago the American manufacture had some small amounts of of what was referred to as ugly fuse. I don't know if it was sold or not. If it was, I don't know what distributor bought it, but it appears it was light on the coating, not heavy like you describe. A light coating wouldn't cause a situation like you are describing. There are several pyro suppliers importing cheap Visco type fuse from China, England, Korea and South America that as varying amounts of NC coatings and in some cases none at all. It may be one of those imported products. Edited January 15 by Pyrogeezer
cmjlab Posted January 15 Posted January 15 Well I figured I'd bring it up with our resident Visco expert. If I recall, it was the last batchi bought from pyrocreations.com a couple years ago. Since then there is a guy who sells on here and Fireworking.com (Posty44 I think). Those rolls of fuse are quite a bit cheaper and much better quality American Visco. My only regret is he doesn't sell the different speeds of fuse. That would be handy to have affordable cake Visco instead of getting creative with black match and American Visco to get "okay" cake timing.
Pyrogeezer Posted January 16 Author Posted January 16 Hi cmjlab: Excellent questions, and thanks for the title you bestowed on me 😊 Maybe I can clarify a few facts about American Safety Fuse for you and others that may be interested. The American type of safety fuse of today has been around since the early 1920s, long before the recently developed Chinese pyro effects fuse many pyros use. These special effects fuse are not classified as Safey Fuse. American Safety fuse is has a specific purpose in the industry and that is to burn at a specific rate (for safety reasons) 35 to 38 seconds per foot, or 115 to 125 seconds per M, and using a special blend of black powder only. This standard was adopted many years ago for blasting “in the ¼” and 3/8” sizes” and in the 3/32”-1/8” for pyrotechnic products. It has been manufactured by the same process for over 90 years. This now brings us to the lacquer coating. The lacquer was developed, again many years back specifically for use on the safety fuse. It’s not just any Nitrocellulose lacquer that you can go out and buy in the paint store or online. There is only one company that produced it in the U.S. It contains a low nitrogen NC fiber and solvents that slow down the burning of the coating in order to prevent pre-ignition of the item being fired. I don’t know what type of lacquer the inferior imported fuse producers use but I have heard over the years some of these cheaper grade fuses have had issues with “jumping” and extremely fast burning similar to quick match. The different ROB (rate of burn) Chinese products use KP as an oxidizer along with metals and other fuels for the effect. We have heard that in some cases they have actually used KC as the oxidizer, but I can’t verify this. As compared to the market for safety fuse, the much faster burning special effects type fuse really isn’t there “finically speaking” for us to produce it. As of the present time we cant keep up with the demand for our American Safety fuse. 3
countryboy7978 Posted January 24 Posted January 24 https://cannonfuse.com/cannon-fuse/american-visco-cannon-fuse.html Here is what I mean about the poor lacquer coating. If you scroll down to the disclaimer it states that this batch of American visco is not waterproof due to a poor coating. I'm happy to hear that the stuff you guys are putting out now is up to quality.
TXpyro Posted January 24 Posted January 24 Pyrogeezer, what is your company called? I was thinking about purchasing fuse from y'all.
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