Substitute For Fuse

[ZonerAsh]

Can anyone help me..... No kind of Fuse is available in my country. I need it for my science fair in school to make a sugar/kno3 rocket. So is there any substitute for that? Can i use Magnesium ribbon or something else? Please help me out

[schroedinger]

Magnesium ribbon will work, even it is a little overkill.

 

Maybe you should think about making you own e-match or black match.

 

If you don't want to handle the needed comps, just get some NiCr wire out of a toaster, bend it into a spiral, solder some wires to it and make it touch the propellant. This will need a quite good power source like a Pb battery or a attery charger and a switch where you cut the power off. If you let the power on too long you can serious damage a battery cut the power after 1 -2 seconds

Edited December 7, 2014 by schroedinger

[ZonerAsh]

Do I have to make the whole propellant to be burned by the fuse/mag ribbon etc or the purpose if these things is just to ignite the fuel/propellant ? Will whole propellant burn itself ? I am confused whether to fill the drilled hole in propellant completely with the igniter (fuse/mag ribbon/ black match etc) or just a spark is needed ? If just a spark is needed so will spark be suffice to make whole propellant burn on its own?

 

Sorry if these foolish question bother you.... I am a newbie actually And I don't have enough time.... I have to finalize the project Tomorrow

Edited December 7, 2014 by ZonerAsh

[Ubehage]

For KNO3/sugar, it actually depends on how you made it, and how well it is made.

 

For the solid/melted compositions, just a spark is needed. (A HUGE spark, make sure to have a few pieces of fuse-material to make the spark).

But for the powdered compositions, you need a bit more of ignition: Either a direct flame for a few seconds, or a fuse that will eject sparks at the same spot.

 

Fuses are actually quite easy to make, using KNO3 and sugar.

Dissolve a bit of KNO3, in water. Then add some sugar, and dissolve that as well. Use PLENTY water, you want to keep the mixture liquid.

You don't need more than a quarter cup; and even that is more than you need

 

Then take some cotton-string, or similar, and soak it in the liquid. Hang it to dry, and maybe trim off any extra clumps along the string.

 

This fuse will burn at a somewhat constant rate. However, do NOT trust it to do so!

[schroedinger]

If you have to finish it tomorow, then the best will be to take some tissue paper wrap, put wet with alcohol and put on line of powder (pref black powder if you don't got rcandy) at least 20 cm long and roll it up or use the e-match.

Everything containing water won't dry until tomorow

Edited December 7, 2014 by schroedinger

[OblivionFall]

A sparkler would probably work. It would be a pretty long fuse and it would be pretty brittle too.

[Jakenbake]

No harm will come to the battery if you design the circuit like it should have been by putting a fuse inline. You also don't need a cumbersome 12v lead battery. You can make something that would work fine with a battery tray for 8 cells, preferably C size or larger.

[BurritoBandito]

Do I have to make the whole propellant to be burned by the fuse/mag ribbon etc or the purpose if these things is just to ignite the fuel/propellant ? Will whole propellant burn itself?...

Ideally you'd light as deep into the core as you possibly can. The flame will ignite the rest of the core as it works it's way toward the nozzle.

[Milyan720]

Sparklers are good but you can make these fuses which work as well

[dagabu]

Understand that this type of fuse is an open type fuse and will ignite from the side when an errant spark from the flame end lands anywhere along the length. Also keep in mind that this type of open fuse is VERY hygroscopic and will absorb water quickly making it useless in high humidity locations.

 

This is why coated and wound fuse is so popular, it is hard to light from the side and remains burnable even in damp conditions.

[BurritoBandito]

Sparklers are not good as fuses. They are designed to spark, and suffer from the same side ignitability which Dag mentioned above.

[OblivionFall]

Sparklers are not good as fuses. They are designed to spark, and suffer from the same side ignitability which Dag mentioned above.

Is side igniting an issue? Do you want the flame to ignite the rocket right inside the nozzle as far in as possible?

[alexpyro101]

Sparklers are good but you can make these fuses which work as well

This, is probably your best bet.

[BurritoBandito]

Is side igniting an issue? Do you want the flame to ignite the rocket right inside the nozzle as far in as possible?

Yes, and yes.

[ZonerAsh]

I used tissue as a fuse to give ignition to propellant .... All the fuel burnt but it didn't fly .. what should I do know ??

[rogeryermaw]

some details about your design would allow better advice to be given. motor casing, nozzle specs, core depth, compositions measurements, rocket design and weight etc.

[Milyan720]

Try following this tutorial its simpler than what some others might suggest

You should also check out his channel

How To Make Sugar Rockets:

Edited December 10, 2014 by Milyan720

[ZonerAsh]

I watched a video tutorial of "grant thompson the king if random" on youtube. The rocket was not very hard to make. But the fuse was nat available so used tissue paper and made a fuse like thing , by the propellant left over. Though it was not burning like a fuse but it was the only choice. So i pushed it inside the rocket. Just one inch of tissue fuse was in physical contact with the propellant. The rocket was lying horizontally on a wood piece as it was a test rocket so I did not managed a proper lauching stant. But i dont know why it did not fly? Does fuse matter that much? I did not know. Or is there any other problem which did not let it fly.

The propellant was in powdered form and i used 7/32" drill bit to drill the nozzle. I have made another rocket and trying to make a proper fuse now. And thanks to all who tried to help. I thank you again.

[ZonerAsh]

I used 5" pvc with 3 inches of propellant and one inch of clay caps on each side. The propellant is compacted by hammer.

[stix]

I watched a video tutorial of "grant thompson the king if random" on youtube. The rocket was not very hard to make. But the fuse was nat available so used tissue paper and made a fuse like thing , by the propellant left over. Though it was not burning like a fuse but it was the only choice. So i pushed it inside the rocket. Just one inch of tissue fuse was in physical contact with the propellant. The rocket was lying horizontally on a wood piece as it was a test rocket so I did not managed a proper lauching stant. But i dont know why it did not fly? Does fuse matter that much? I did not know. Or is there any other problem which did not let it fly.

The propellant was in powdered form and i used 7/32" drill bit to drill the nozzle. I have made another rocket and trying to make a proper fuse now. And thanks to all who tried to help. I thank you again.

 

Don't worry about the fuse at this point. Hang back and take your time.

 

I like that you are doing 'static' tests before trying to fly it. It shows your consideration and respect about safety. Keep on that path until you are satisfied that you have a rocket that isn't going to fly sideways a few seconds after launch and hit something or someone.

 

I haven't seen the "grant thompson" method and I probably won't, I've seen that sort of thing enough times. I mean no disrespect to him or others who post "easy pyro how to's" on youtube - you will get much more informed advice on this forum, especially if you are prepared to do some research yourself and ask the right questions.

 

[EDIT sort of] Ok, so I DID watch the "grant thompson" video. I guess I had to because that is what you are experimenting with. One of the better produced ones and pretty slick. But...

 

I'm glad I did watch it, because I believe there is a potentially dangerous omission! (or two).

At about 3:10 in, he describes how to "add the white mix" (lame description anyway) - this concludes at around 3:25.

 

Not once does he mention that the "white mix" should be added in increments. To the uninitiated It's as though it should all be piled in at once and rammed. Well, I have very big issues with that. As with bp, if the fuel is not compacted enough it could easily result in CATO and shards of PVC flying everywhere!!!!... Especially a concern if lighting closely with an unproven fuse.

 

Also, this method and instruction is too variable, ie. exactly how fine the KNO3 is and exactly how long it's all "shaken" together can make a significant difference... hmmm, "the king of random" indeed!

 

It would be very interesting to do an experiment: Get 10 people together, probably between the ages of 15-25 that have no experience with sugar rockets (or any other pyro), supply them with all the equipment and ingredients, have them watch the video and say "go for it"... I'm sure the results would be as varied as the instructions are. (btw. did I mention my German heritage? )

 

Perhaps I'm being hysterical? I'm very interested to see what others on this forum think about that vid.

 

ZonerAsh: research, take your time and do it properly.

 

Be Safe.

Cheers.

[ddewees]

I just watched it, and think it's great. Boy, I wish they had YouTube when I was a kid... it's like Mr. Wizard on steroids.

 

The guy was very easy to listen to, and he gave good explanations for most of what he did. Mentioned all the safety warnings too.

 

Did he leave anything out?? Sure, I guess. Like you said, loading the propellant in increments wasn't mentioned, and the rubber mallet it's very useful... but the pvc fear I don't get. Any goofy kid winging this together is going to run for his life the minute something gets lit... it's just natural. It's also probably the greatest moment in the whole experience, right after seeing it blow up or actually fly.

 

To me, it's what growing up is supposed to be like... but that's just me.

Typically, these are phases in a kids life... six months from now, he won't give a crap about any of this stuff (maybe). Telling him to slow down or not do certain things is (to him) taking half the fun out (or more), and likely will just make him stop asking questions about those things.

[stix]

I just watched it, and think it's great. Boy, I wish they had YouTube when I was a kid... it's like Mr. Wizard on steroids.

 

The guy was very easy to listen to, and he gave good explanations for most of what he did. Mentioned all the safety warnings too.

 

Did he leave anything out?? Sure, I guess. Like you said, loading the propellant in increments wasn't mentioned, and the rubber mallet it's very useful... but the pvc fear I don't get. Any goofy kid winging this together is going to run for his life the minute something gets lit... it's just natural. It's also probably the greatest moment in the whole experience, right after seeing it blow up or actually fly.

 

To me, it's what growing up is supposed to be like... but that's just me.

Typically, these are phases in a kids life... six months from now, he won't give a crap about any of this stuff (maybe). Telling him to slow down or not do certain things is (to him) taking half the fun out (or more), and likely will just make him stop asking questions about those things.

 

Ok, I didn't mean to come across like a "killjoy" and perhaps my post was a bit alarmist, but I stand by it. You can still have fun whilst having an applicable level of safety at the same time.

 

Sure, we've all done reckless activities when we were younger: smoking cigarettes, drinking too much alcohol, train surfing, taking lsd... etc. perhaps even all at the same time. When it comes to pyro experiments and mucking about with potentially explosive chemicals, my view is to err on the side of caution and take advice from others if unsure.

 

Fair enough that r-candy is not as volatile as other compositions, but still worth considering the potential dangers.

 

If you read my previous post before your eyes glazed over, you would have seen that the only text that was emphasised in black bold italic type was:

 

"Especially a concern if lighting closely with an unproven fuse."

 

My only regret is not underlining the word "unproven". That was the point I was getting at!!, and my main reason of concern.

 

A sparkler can be used - tightly wrapped in five or so layers of aluminium foil helps mitigate any issues of an 'errant spark' igniting the motor prematurely. I've used this method without problems when not wanting to waste my precious e-matches, which took me considerable effort to make.

 

ddewees, I've watched a couple of your Vitamin F assisted vids - I love them, great stuff and in beautiful surrounds . I am a novice in that area, but a novice does not necessarily equate to idiot.

 

Therefore I have to question and take you to task on this comment:

 

...Telling him to slow down or not do certain things is (to him) taking half the fun out (or more), and likely will just make him stop asking questions about those things.

 

I hope you don't mind me telling you this, but I find that comment utterly absurd!

 

I'm not going to bother to explain why, except to say that if (him) unfortunately has an accident, I'm comfortable with everything that I have posted.

 

Cheers.

 

[EDIT] The rubber mallet is not very useful - it's counterproductive. A regular metal hammer gives a sharper more definite blow, resulting in better compaction. Remember this is powdered r-candy, NOT whistle or flash.

 

I'd even go one step further to say that him using that rubber mallet (in the vid) simply confirms my initial concerns regarding the quality of information provided. Using the rubber mallet could possibly leave holes in the r-candy, similar to the holes in the video... tee hee heee heeee - yes, a slick production, but . . .

 

Anyway, I should go to bed now before something else happens.

 

Cheers

 

For the op, if you're serious, check out:

http://www.thefintels.com/aer/rocketindex.htm

http://jamesyawn.net/candyrocket/

and the Master: http://www.nakka-rocketry.net/

 

Edited December 12, 2014 by stix

[ZonerAsh]

So this is the rocket that i made. Can sombody tell me why i did not fly?

[BurritoBandito]

The video did not load for me on my POS phone. Step us through the process you used. For example; what was your fuel? 65:30 KNO3:sugar? Did you melt it? How did you consolidate it? What was your casing ID and length, your nozzle, etc.?

[stix]

Burrito, I believe he used the powdered method & specs from this video:

 

ZonerAsh, I watched your test video. There are many variables to consider, therefore it's difficult to give an explanation of why it didn't fly.

 

I have to say that I was dismayed at the three people standing approx. 2 meters from the motor during the test. Therefore I'm hesitant to give you information to improve your rocket motors until you can show some respect for safety - others may have a different view.

 

However, one thing I noticed was the fuel seemed to "splutter" which could indicate that it was not ground fine enough, or mixed well, or perhaps your KNO3 is poor quality.

 

Please light the fuse and stand back as far as possible.

 

Cheers.

Edited December 14, 2014 by stix