pudidotdk Posted September 20, 2007 Posted September 20, 2007 I have two guesses. Either the funnel is too wide and the black powder might spill.Or the two wheels with the stringspools on are not having a high enough RPM, which gives too little cover around the blackpowder.
Givat Posted September 20, 2007 Posted September 20, 2007 looking on the fuse I see I got about 1 full spin of the strings for every 1 c"m of fuse. I'll try making it spin more for each length of fuse and see how it helps ---edit--- I Just pulled my fuse slower so the ratio of RPM per length of the fuse has grown. Still no BP in the fuse =\
hashashan Posted September 20, 2007 Posted September 20, 2007 Tap the funnel while making the fuse. And can you provide a picture of the place where the strings enter the first pipe' It has to be of a certain form in order to catch the powder
tentacles Posted September 22, 2007 Posted September 22, 2007 Do you have a small tube on the end of the funnel that the strings wrap around just a little? This helps form the net that the BP will drop into. Someone had a really great picture of their funnel, but I can't seem to find it. It was just a small piece of brass tube that slid down just below where the strings "fall down" the spindle. This helped keep the strings from just forming a rope.
Givat Posted September 22, 2007 Posted September 22, 2007 I took apart my visco machine and found out I got caked BP in my first pipe.I think I'l try some anticaking agents like Sodium bicarb or calcium carbonate in small percentage (5%) in my BP and see if this helps. tentacles, your idea sounds very intresting, can you try to draw it?
FrankRizzo Posted September 22, 2007 Posted September 22, 2007 Both sodium and calcium bicarb will slooow down your powder at 5%. Commercial mfg. press and granulate the mill powder to very small grains to allow precise flow control.
tentacles Posted September 23, 2007 Posted September 23, 2007 You guys are in for a real treat here, my masterful Paint skills: http://www.apcforum.net/files/powderdiedoohickey.jpg
Givat Posted September 23, 2007 Posted September 23, 2007 thanks for the painting, the idea looks good but I can see one problem - In a big funnel we all got problem in BP flow. I guess in this brass tube going in the device we just wont get any BP flow.
tentacles Posted September 24, 2007 Posted September 24, 2007 Givat: are you using tracer strings? Normally you have one or two (four in time fuse, usually) threads going down the funnel and ending up in the core of the fuse. These threads help pull the powder down the funnel. Have you tried using granulated BP? I would reccomend corning dust, from breaking up pressed pucks. I've got a bag that I keep adding to, of 30- mesh stuff. I read somewhere that GOEX used to sell 50 mesh BP to visco for their fuse.
Maciek Posted November 23, 2007 Posted November 23, 2007 Hello,It's my homemade visco machine. http://www.fotoszok.pl/albums/userpics/10735/DSC00300.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00291.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00292.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00294.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00295.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00299.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00196.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00197.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00288.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00289.JPGhttp://www.fotoszok.pl/albums/userpics/10735/DSC00290.JPG and movie:http://pl.youtube.com/watch?v=gf7Xb7PbK8c Maciek
Zmuro Posted November 23, 2007 Posted November 23, 2007 Nice. Could you post a video of a burning fuse.
Sylar Posted November 23, 2007 Posted November 23, 2007 How come I feel druk when I watch that video Are the spools really leaning or is that a visual effect from the camera? Nice idea about the excentric tapping the funnel to keep the powder in motion! I keep having problems with my belts slipping ... gotta find me some chain-like system or perhaps gears. Oh yeah, for those who are wondering: The eventual fuse diameter is solely defined by the diameter of both holes in the dyes. I made the mistake of drilling them to 4 mm, giving me just a massive BP core. Suitable as time fuse when coated with tar or something I believe, but far too thick for ordinary use!
FrankRizzo Posted November 23, 2007 Posted November 23, 2007 Take a look at the Google books preview of "Selected Pyrotechnic Publications of K.L. and B.J. Kosanke." (1995 ed.). On page 94-95, there is a good discussion about how mesh size and grain spacing contributes to burn speed. For normal speed visco, the author specifies -100 to 40mesh as the particle size distribution.
iclazion Posted December 20, 2007 Posted December 20, 2007 I would like to know if any one out there could help me with the following questions: I am struggling to get my hands on a 100% cotton thread/spool is there a substitute i can use that will work as good as the cotton would. The tunnel that the top threads run through, "what is the smallest inside diameter i am allowed to make it, because at the moment is is about 1.8mm and i am worried that it will be to small to run my 12 + 2 feeding threads through with the black powder. At the bottom i am also using a 1.8mm diameter and i am scared it will pry itself closed in the tunnel.
pyrogeorge Posted September 30, 2009 Posted September 30, 2009 How can you make different sizes of visco fuse?for example 2mm,3mm,6mm..
TheSidewinder Posted September 30, 2009 Posted September 30, 2009 You use different sized dies, and increase the powder flow as the fuse size gets larger.
pyrogeorge Posted September 30, 2009 Posted September 30, 2009 But how to increase the powder?Bigger funnel for example?
FrankRizzo Posted October 1, 2009 Posted October 1, 2009 Right. As the opening in the funnel becomes larger, the "column" of powder coming out also enlarges. The fuse is often also later passed through a tube (die) that compresses the fuse a bit smaller than it was originally formed, in order to ensure a consistent diameter and powder density inside.
Updup Posted November 24, 2009 Posted November 24, 2009 Right. As the opening in the funnel becomes larger, the "column" of powder coming out also enlarges. The fuse is often also later passed through a tube (die) that compresses the fuse a bit smaller than it was originally formed, in order to ensure a consistent diameter and powder density inside. So a question for the people who have made a visco machine: how many turns of the thread wheels are made per foot of fuse? This seems like a project I might want to get into, but is it worth it? I can get visco 8 cents a foot is it really cheaper to make your own?
scarbelly Posted November 24, 2009 Posted November 24, 2009 I wouldn't do it in an effort to save on money unless you use a LOT of visco fuse. Unless you have a lot of scrap parts, building the thing will probably not pay off for a while. The main reasons it seems to me that an amateur pyro would want to do this are: 1) factory made visco is unavailable, or 2) it's just a fun project! The second one being the most likely for us here in the U.S. of A.
dagabu Posted November 24, 2009 Posted November 24, 2009 I would like to know if any one out there could help me with the following questions: I am struggling to get my hands on a 100% cotton thread/spool is there a substitute i can use that will work as good as the cotton would. The tunnel that the top threads run through, "what is the smallest inside diameter i am allowed to make it, because at the moment is is about 1.8mm and i am worried that it will be to small to run my 12 + 2 feeding threads through with the black powder. At the bottom i am also using a 1.8mm diameter and i am scared it will pry itself closed in the tunnel. Check this out, I get thread from them for black match. http://cgi.ebay.com/12-000-Yard-Cone-Tex-4...=item3c9bfd6aa6 D
oldmanbeefjerky Posted August 4, 2011 Posted August 4, 2011 i think tomorrow ill take advantage of the large aluminium bars (round) lying around in my metalwork class, and the big fancy aluminium cutter, to build two aluminium dies, in preparation,then once i build my MOT welder, i think ill go and build myself a vico fuse machine.out of aluminium and wood. with either this guys design or the other design (one die under the other). visco fuse is so very difficult to come by in australia, i wonder why i even considerd paying $$45 for 15M of visco from bargainmart, when i could make my own!
dagabu Posted August 4, 2011 Posted August 4, 2011 $.04 a foot at PGI... Need me to send you a spool of "green lacquered twine" for Christmas? -dag
busspuppy Posted August 4, 2011 Posted August 4, 2011 $.04 a foot at PGI... Need me to send you a spool of "green lacquered twine" for Christmas? -dag Dag are you talking about Chinese or American Visco? I am unsure what kind of fuse you are talking about. If it is let me know I would definantly vbe interested in some if you are willing and it is legal to ship. Just PM me. I could really use some visco. Eric
Recommended Posts