time fuse- punched vs. cut

[Fotia]

Yep. I was just texting him about that.

[OldMarine]

I have 5 tabs open on my laptop right now and one is Caleb's site. I like to be able to price my new whimsical ideas in real-time.

[dagabu]

Fotia,

 

At PGI, I like to wander the fields early in the morning and look for rocket sticks, un-exploded shells and duds of all kinds. While I do follow all the rules tied to picking up duds, I also like to look at what caused them to be duds.

 

In almost all cases, its a simple failure to transfer fire. Of course, that means one of two things; failure to transfer fire to the fuse and failure to transfer fire to the burst. While I have found a couple canules that failed to take fire (the black match was missing and the passfire was un-scorched), it's time fuse that represents almost all of the failures I have found.

 

I keep a multi-tool on me and I simply roll the time fuse out of the shell and I have yet to find a shell with the black match missing or burnt off on the inside of the shell, although I have heard of it, I have not seen it.

 

My findings have been pretty close to 50/50 between split and tied vs punched time fuse. I know Ill get a bunch of push back on this and that's why I haven't brought this up here before but I do think we need to talk about this openly and see if we can make some conclusions that help us all make better shells.

 

In almost all cases, the culprit seems to be the match and not the fuse, although there are some, perhaps 20% or so that do burn and it looks like the time fuse lit but didn't transfer fire to the other end. I dont know why though.

 

This was more of a curiosity for me so I didn't really look closely at them all so it may very well be more one sided than I saw. I do think it's a good thing to consider when making the shells, to slow down and pay close attention to the details for a better outcome no matter which method you chose.

 

A couple comments on the top-hatting TR uses. After speaking with Tom for several hours over many years and carefully reproducing the timed reports he makes so carefully, I have only seen one of Tom's and just a handful of mine not work as advertised using the top-hat fusing method he uses.

 

Remembering our conversation from many years back, he told me that a slower but more consistent black match, hand pulled, yielded better results. Priming the fire giving end inside the caps with the identical prime gave great timing to the report. All of the ones that failed to light were made using commercial black match, as I was trying to save time... Not a good idea.

 

Take this for what it's worth, I'm not advocating one method over another, many cats to skin, find your way but be careful to listen to those that have the experience in this arena.

 

Stay green and good luck.

[calebkessinger]

Dave,

I wonder how folks attached the crossmatch to the time fuse most of the time and if that had anything to do with the failure?

Do people normally pull the match tight and tie it up after punching? or do they just leave it loose?

[dagabu]

Of course my answer will be relying 100% on my memory, this is not the most reliable thing as far as I'm concerned. I'll give it my best shot

I don't remember ever finding a single punched time fuse that was tied after it was punched and the black match was threaded through the hole.

The same thing goes for split black match, I have never seen it not tied after it's been split and the strands of black match laid inside the split.

Of course, there are the Chinese ball shells. Many of the smaller sizes seem to have the time fuse cut at a 45 degree angle and a small dab of prime put on the end of the fuse. Many of these appear to have the time fuse burnt all the way to the prime but the prime fail to take fire and light the shell.

[calebkessinger]

Thanks Dave.

It's nice to know what people did and what didn't work.

Sure seems weird a bunch a shells don't get fire transferred.

[dagabu]

Oh, NO! It's not a bunch by any means! I find perhaps two every morning out of the thousand (?) that were launched in shows or at the rocket line or from the B line. Of course, I am only walking around for an hour or so and if they are putting a show together, I don't go anywhere near.

 

Even more entertaining is just picking up the debris and turning it over in your hand and envisioning the work that went into each shell. Each fragment has a story, each layer is a moment in time. The smell is divine, the string hanging off of the end disks is almost animal in its structure.

 

I recommend a walk in the back field to everyone.

[lloyd]

Almost poetry, Dave!

L

[dagabu]

[calebkessinger]

[dusty56]

Just a quick comment. I use the split, insert and tie method. I've never had a misfire.I do one thing a little differently however. I found that single edge razor blades get dull very quickly. I have a pair of fuse cutters that are blade and anvil design. I put mark 1/2 inch from the end and use them to split the time fuse length wise. Insert at least two strands quick match and clove hitch. Goes pretty quick.

[starxplor]

I have only made 2 shells so far, both used the split with anvil cutters, slide in match, and tie with clove hitch method on both ends. All 4 ends took/passed fire and the two shells lit as expected.

 

Given how much the time fuse halves bent after sliding down the match, I would worry about the match dislodging if not tied in.

[lloyd]

I never responded to Caleb's question. Most punched cross-matching is held in by pinching the fuse with pliers after the fuse is threaded through the hole.

 

Starxplor, I have seen an example of where the fuse was not tied shut after slitting and cross-matching. On one shipment of Chinese shells, we saw that they had split the fuse, laid in one or two strands of match, then bent the match down to the BODY of the fuse (toward the shell), and tied it there.

 

Then, instead of closing and tying the split, they dribbled a bit of priming slurry into the 'crotch'. That more-or-less locked things together, and prevented powder from being loosened from the exposed surfaces of the split.

 

I guess it works OK... but it appeared to be more work and expense than merely tying the split.

 

Lloyd

[calebkessinger]

Thanks Lloyd.

[starxplor]

Ahh, with slurry that dries I can see it not being a problem of falling out. Maybe a factory ran out of string one day and had to improvise to make their quota, heh.

[Livingston]

Shot my first 6" at 2f 2 years ago and no ignition so after an hour after scavenging the range I found my shell and member who's building professional asked me did you pinch the time fuse with pliers because I punch my TF. so I says no and was like you need to that! Never had a problem since. While working with cylinder shells I like useing spollettes(whistle) ;-)

 

PS I know a fella who's doesn't use BM at all to prime his TF and he's made 100's of shells!! Brad come chime in!!

[Wiley]

I know for fact that Braddsn uses no prime on the fire-giving end, and simply splits open the fire-receiving end. No black match. He's had no issues that I know of, and has built and shot literally thousands.

 

I split what time fuse I use with a single edge razor to the depth of the blade (1/2"). Put in a couple strands of match and tie the split closed with 4 cord waxed linen lacing.

 

Mostly I use spolettes, which to me are easier to prime, and prime reliably.