Visco Fuse failure

[HissingRDX]

What are the odds of Visco burning rapidly down the length of the fuse leaving no time to get away? Is it possible the NC lacquer coating can burn much faster than the BP core making a terribly dangerous situation? I have heard of fuse doing this, but not sure it was Visco fuse.

 

This is standard visco fuse is from CannonFuse.com

 

 

[leedrill]

i have asked this question before out side of a post and never really gotten an answer ive wondered the same thing about pic {plastic igniter chord }

and also thermalite

 

it makes me wonder how safe saftey fuse really is not knowing the comp inside of them especially knowing some are perc based

 

i hope this thread gets some info going on fuse gone wrong situations id love to hear if there is any horror stories out there to make people just be that bit more safe lighting fuses

[nater]

I have never seen visco burn so fast one could not get away. I have seen it take fire from the side or spit enough sparks to light something else, so I would not use it to light a pile of loose comp. Last year, we had cases of 1.3 shells with QM leaders with a length of visco heavily coated with a BP slurry. Even when lit at the side, the slurry burned off and only igniting the fuse from the end. This 2-3 second delay was unnerving when i was expecting instant ignition.

 

The only fuse "gone wrong" situations I have experienced are with traditional QM leaders with a few inches of bare black match for delay. It is easy to get hot gasses to ignite at the piping causing a nearly instant ignition when you may not want it.

[a_bab]

There are quick visco sorts, like 10 cm (4")/sec. burn time. Having such a fuse around and pulling the wrong one from the box will certainly ruin the day.

 

There's also the QM effect visco is capable of in a piping, hence the need to wrap it tightly if you have to depending on the application (replacement of TF in a shell).

[Sparx88]

I have never had a problem like that with any visco. Just don't trust stuff that has been all bent to hell and loose. Use only the stiffest freshest cuts. No need to mess around using old fuse that has gone soft or has been handled by a baboon. You can make 30 sec per foot visco burn like 10 second per foot by balling it up into a, ball and soften the poop out of it. But then why? Buy the right fuse for the job and CannonFuse.com has great fuse.

[psyco_1322]

Some of the American visco is double coated with NC lacquer. It's very shiny/glossy fuse, and the coating will certainly burn off the fuse, even if you don't actually get the fuse ignited. I have never see the burning coating ignite the fuse, and it does burn off faster than the fuse actually burns. In my opinion, that could lead to a dangerous/scary situation. Most other visco seems to not have an issue with the coating burning separately and are relatively safe in my opinion.

 

I have seen those shell leaders with visco on them, and I'd agree they are not really something you want when doing a hand lit show.

[schroedinger]

There are some differences in Visco fuse.

Cheap made visco it can happen that the nc burns faster than the fuse itself.

Also there are different burn speeds, ranging from 0, 75 cm/ s up to 10 cm /s. And also sometimes special one which are faster.

 

I know one time i saw a visco witch had a burn speed of about 30 cm /s.

 

So always check witch one you have.

 

Also depending on the coating and twine used, there is visco which takes fire from the sides qnd some that won't. Check for that. The easy one can becomme quickmatch if it gets covered.

 

Depending on what you wqn't to achive use the right fuse, and don't be so foolish and try to safe on this part, better spend a buck more and be safe then saving 10 bucks qnd be sorry.

[pyrojig]

I second what psycho said. It is not uncommon for the double coated visco ( usually american cannon fuse type) to have the lacquer burn on the surface of the fuse. I too have never had a ignition down the line ( bit it could happen if the fuse is compromised , bent or core exposed). IT is more a scare than anything.

The use of perch comps as Leedrill brought up is a good point . They are over-fueled on the slower fuses, so even if the comp was loose or the fuse mishandled , it would most likely burn a bit faster in spurts, but not the length of the fuse. Faster fuse may pose more of a prob if loose. I have had some leader fuse Perch based that was about 1/2 the speed of QM and if it where loose it may be even faster( but no one would be testing ground items with this, or anything close to them( that wasnt in a tube) .

Edited January 22, 2014 by pyrojig

[Mumbles]

I've sort of ran into this situation where the NC coating burns faster than the fuse itself. This seems scary, but I've never had it cause an issue. It often extinguished itself after a few seconds. I've never had it get through even a mild choke either. I tape on the visco to my quickmatch leaders for most club shoots. The NC layer burning has never penetrated the tape. It's also never penetrated the wall of a tube for a cake, or the choked paper bundle at the top of fountains. I'm not saying that it can't happen. It just hasn't happened yet to me.

 

I find lighting the fuse with a torch prevents the coating from lighting without the core. As long as the core lights I just walk away. If the layer happens to ignite it early, I'll be surprised but nothing more.