Fotia Posted January 12, 2017 Posted January 12, 2017 I hope this is the right place for this. If not could the administration move it. I did a search but couldn't find any discussion about it; so here goes. I have already made a time fuse punch to go with the adjustable time fuse cutter I made, but a few weeks back, I read somewhere that it was better to cross match the time fuse by cutting/splitting it rather than punching a hole because sometimes the tar gets pushed through & covers the B.P. causing a passfire failure. I remember when I built some shells in Tim Caney's class & 1 of the shells didn't light the bottom shot. After reading about some people's preference to split the fuse, I thought maybe this was what happened? But the entire "fuse" is burning and should touch the cross match if it is properly folded over and slurried, right?
lloyd Posted January 12, 2017 Posted January 12, 2017 (edited) Fotia, The largest problems with punching are two:1) As you heard, tar can be smeared over the powder core, and at the least, delay ignition; at the worst, prevent it.2) Many punches sold today are of the "plug cutting" variety... they REMOVE a plug from the fuse. This can be disastrous on fuses with small powder cores. If it removes the entire core where it's punched, then the black match is only touching the bitter-end of what's remaining of the core in the body of the fuse. I introduced Ned Gorski to the 'split and tie' version of cross-matching at a shell-making seminar I taught a few years ago. He's never looked back. I and (I believe) he have NEVER had a cross-match fail to pass or take fire with that method -- over many thousands done that way. (commercial manufacture, for me). In order to avoid the 'tar smearing' the blade must be worked down more-or-less straight from the end to the timing mark. It can be 'rocked' a bit, but mustn't be used in a 'slicing' way, unless it's done in one pass without 'sawing' motions. You DO have to be very careful to split it EXACTLY in half, so you're centered in the powder core. It works a treat, and is as accurate for timing as any other method. It's quick. There's no 'fooling with the match', trying to get it in the punched hole, and you can use two or three strands as easily as one (double insurance!). There's no 'crimping' of the fuse to the match, in order to ensure contact between match and powder core. Try it! Lloyd Edited January 12, 2017 by lloyd 2
Fotia Posted January 12, 2017 Author Posted January 12, 2017 (edited) Looks as if I will have to design & build a machine that will "plung" cut the fuse from the end whilst holding it in place. Seems easy enough, but knowing me I'll complicate the hell out of it. Edited January 12, 2017 by Fotia
Nessalco Posted January 12, 2017 Posted January 12, 2017 I split and tie, and find it to be quicker and easier than punching. Also much cheaper. Kevin 1
lloyd Posted January 12, 2017 Posted January 12, 2017 Well, until you decided to build a machine to do the slicing, it WAS cheaper, because all you need is a sharp razor blade... no punch! LLoyd
Nessalco Posted January 12, 2017 Posted January 12, 2017 (edited) Can't speak for Lloyd, but I usually go 3/8" to tie in two strands of match, 1/2" if I want to use 3 strands. I use cotton crochet thread (Red Heart #2) to tie the match in place. Slit the fuse, place blackmatch, then throw a clove hitch around the fuse above the match. Six turns to tighten everything up, then another clove hitch. (Quicker to do than to write it down) KO Edited January 12, 2017 by Nessalco
lloyd Posted January 12, 2017 Posted January 12, 2017 I pretty much always cut 1/2" deep, regardless of the number of strands of match... but I seldom use only one strand. I don't do the 'multiple turns' Nessie does. I tie one clove hitch fairly close to secure, then another even closer to the match to tighten it up. Even if the match isn't exactly dead in the bottom of the slit, the slit, itself, forms a sort of "quickmatch effect" that causes the timing to be determined by the distance between the bottoms of the two slits. Lloyd
Mumbles Posted January 12, 2017 Posted January 12, 2017 I slice and tie as well, about 1/4 to 3/8" depending on how much crossmatch I want. Dental floss is easy, thin and strong for the tying application and keeps your shells minty fresh. Otherwise I pull my cotton string apart into individual plys. Thin is helpful, so whatever you have around. You did mention that you made yourself a fuse cutter. If you're going to be trying to do any precision timed effects like TR, or something like that another priming method will be required. Cutting or punching timefuse negates any real precision of your cutter. "Top hatting" is commonly done, which is essentially tying or securing blackmatch or a blackmatch band over the top of the cut fuse.
Fotia Posted January 12, 2017 Author Posted January 12, 2017 The seminar TR gave in Penn is where I got my first idea for a cutter. Then I saw pics of others similar around the web. I do believe you are correct as TR does do some sort of blackmatch cover over the ends of his timed reports. Dental floss is way too exspensive, unless you use your "used" stuff. LOL
Carbon796 Posted January 13, 2017 Posted January 13, 2017 Razor blade slice, 1/2" length, 2/3 pieces BM, as well. On most standard single edge razor blades, the length of the blade to the reinforced back is a 1/2" so there's no extra measuring. Cut to timing length + 1", split both ends, done.
calebkessinger Posted January 13, 2017 Posted January 13, 2017 http://www.woodysrocks.com/store/p130/Fuse_Spilter_.html Super easy it is. Just put a razor blade in a rod. bam done. Working on a new design of fuse punches that should be just as easy right now.
Fotia Posted January 13, 2017 Author Posted January 13, 2017 http://www.woodysrocks.com/store/p130/Fuse_Spilter_.html Super easy it is. Just put a razor blade in a rod. bam done. Working on a new design of fuse punches that should be just as easy right now. Looks too simple & as I said, I like over complicating things. LOL. I started sketching us a design while at work yesterday & added it to my ever growing list. I've bought some stuff from Woodys. Great service. So do you think that splitting & cross matching is more idealistic than just capping the end with black match & slurry like TR does?
pyrokid Posted January 13, 2017 Posted January 13, 2017 As far as I know TR uses the aforementioned "top hat" method which consists of homemade 5 strand flat match being secured flat across the face of the square cut time fuse. Splitting can probably be made to be more time efficient, but the top hat method seems from the outset to be the best method to ensure tight, accurate timing. I have a notion that fuse splitting should in principle be the more reliable method as far as ensuring ignition goes, but there are many examples of TR's cap plug rockets demonstrating that great reliability is possible with the top hat method.
Mumbles Posted January 13, 2017 Posted January 13, 2017 I don't want to take this more off topic, but an underlying part of the success of the tophat method involves using good quality time fuse with a good powder core. I agree though. It seems to work reliably. I would trust split fuse more personally. The top hat method is not something I've ever tried, but am thinking about it.
Ubehage Posted January 13, 2017 Posted January 13, 2017 I don't want to take this more off topic, but an underlying part of the success of the tophat method involves using good quality time fuse with a good powder core. I agree though. It seems to work reliably. I would trust split fuse more personally. The top hat method is not something I've ever tried, but am thinking about it. Due to lack of proper equipment, I've had trouble with both splitting and punching timefuse.I have tried both tophatting and priming, and in my experience the priming might get blown off by the break. Whereas I never had a failed ignition with tophatting.
Fotia Posted January 13, 2017 Author Posted January 13, 2017 So just ditch the idea of even split fuse? It would be less work to just top hat & prime, right?
lloyd Posted January 13, 2017 Posted January 13, 2017 Fotia,Tom R is a very experienced and fastidious practitioner. He cares not for how long it takes, nor how carefully he must approach a job, in order to make it work. To be honest, most fireworks folks aren't that diligent. They want to GET IT IN THE AIR, and attention to VERY minor details is often skipped in favor of just "getting it made". You'd be better-off with cross-matching, whether you split or punch, until you're of the experience level and diligence of Tom. Lloyd 1
Fotia Posted January 13, 2017 Author Posted January 13, 2017 Ahh, but you don't understand us machinists. TR & I. While I lack his experience, I am a stickler for detail. When I first got into lasers, for my first one I built a 1W 445nm, which at the time was quite powerful. I now have a few and am working on another custom host with a pretty cool addition. I've only been working on IT off & on for 2 years. I'll probably make a fuse cutter anyway just because I can, & say "look Ma what I did!"
lloyd Posted January 14, 2017 Posted January 14, 2017 "Ahh, but you don't understand us machinists."-0- I don't, huh? I guess you don't know me! <grin> (Just finished a 2.5-hour CNC run at 5:30 on a difficult and complex part...) Lloyd
Fotia Posted January 14, 2017 Author Posted January 14, 2017 Hmm, I thought I read somewhere that you bought your tooling from Caleb? Well then you should get it. While I love pyro, I'd rather take my time & not have too fight my way trying to figure out why something doesn't work because I rushed it. And I get more enjoyment making a tool or device that functions correctly or makes the job simpler.
lloyd Posted January 14, 2017 Posted January 14, 2017 (edited) No. I HIGHLY recommend Caleb's tools. I only make tools for myself and for 'professional clients', not for the general market. I'm in the business of designing formulas, process methods, and tools/machinery, and building manufacturing equipment (including fully-automated machinery) for the pyro trade, but I don't ordinarily sell machinery to individuals. So... the comment about "not understanding us machinists" was pretty amusing to me! Woody's (Caleb) makes the best pyro tooling for the amateur trade I've ever seen, bar none. And he's a fun guy to spend some time with, too! (And he's just "CNC'd" his shop, so he ought to be able to make more, and faster, now.) LLoyd Edited January 14, 2017 by lloyd
Fotia Posted January 14, 2017 Author Posted January 14, 2017 (edited) Maybe I need to come work with you. That way I'd be able to both things I love together. I've only had my shop fully functional for a few months. Took me quite a while to get set up & make some of my own tooling as it was too expensive to buy. I only wished I had a CNC lathe & mill. I would like to be able to make & sell pyro tooling at PGI. I've shown a couple of people at convention some things I've made & they said that I should make stuff for PGI. I wonder why Caleb doesn't sell there? Edited January 14, 2017 by Fotia
lloyd Posted January 14, 2017 Posted January 14, 2017 I believe he does. I believe he did at this last PGI. I don't know if he had a booth, but my recollection is that he did. Maybe he only took stuff there for informal sale. He had a broad assortment of tools for sale at the last FPAG 4F meet. (nice stuff, too! I was even drooling over a couple of them.) I told Caleb that I very well might start buying my _personal_ tools from him, because I couldn't afford to make my own at the billing rates I charge working for other folks, compared to his prices! <grin> Lloyd
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