Who makes thier own igniters?

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BayouRat said:
But isint that in prill form. I've heard if you try and grind it turns to mush.
Click to expand...

Yup. But in this application it's dissolved in warm water, soaked into the paper towel (fuel) and allowed to dry.
Read Jimmy's page for the details.
 
dave carver said:
I think I have the cheapest igniter possible. The wire is a spool of 2 conductor field telephone wire from the military, I think it's aluminum because it will not take solder. There's thousands of feet left on the spool, I got it for a dollar at at yard sale.
Click to expand...

Actually there are four aluminum and three steel strands. At one time it was copper, but aluminum is cheaper and a bit lighter. With the right solder and flux you can solder it, but my memory doesn't serve well enough to recall what to use there.
 
Here is a video I made testing the Rocketflite and QuickBurst kits.

First igniter is made using Rocketflite ML Series (MagneLite). Just a single (non-folded) dip.
Second igniter uses QuickBurst as the pyrogen. Same non-folded wire.
Third test is an igniter that I dipped in Rocketflite pyrogen first, let dry, then dipped in QuickBurst for a multi-layer test.

The MagneLite burns fast. The QuickBurst is a more sustained burn. For the combo test, you can hear the MagneLite ignite first and then the QuickBurst continues. I probably won't dip anymore like that.

[video=youtube_share;__HtI3JA_Ww]https://youtu.be/__HtI3JA_Ww[/video]
 
I don't think you need a LEUP to make your own igniters, as you are making explosive mixtures which is legal, but (yes, but) you do need a license (and not a LEUP, a Type 20/54 license) if you are to transport it.

Now APCP motors need sustained hot flame to burn, so I won't trust blackpowder based mixture to ignite it reliably (I'm sure it can). I use a metallic green star mixture based on magnesium, mixed it with acetone and pieces of ping pong ball to make a slurry. You then use the wire wrapping method to make the igniter bridgewire, dip the thing in the mixture and it SHOULD (I have not tested it) ignite APCP.

You will want at least 1/2" of exposed wire when using the wire wrapping method, because you are wrapping (as opposed to soldering) the nichrome wire onto the lead, it is not a good connection. In the past igniters have refused to work because I left too little exposed lead wires. Good thing nichrome wires are not springy at all so once you wrap it tightly around the lead wire, it stays. Using the 32 AWG nichrome wire from Apogee it will light with a FRESH AAA battery in about 2 seconds or so... using a more sensitive pyrogen under the metallic star mixture may improve ignition time... Unfortunately Eggtimer TRS will not even heat the bridge wire up, let alone light it (42 AWG nichrome + sensitive chlorate based pyrogen may be needed for this)

I'd post formula but since this is not research forum, I don't want to break some rule by doing that, but that formula is in Shimzhu's book and also the archived Pyroguide. In theory any metal burning star mixture will work. The idea is hot sustained burn.
 
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daveyfire said:
F&G is /the/ seminal thermite and intermetallic paper. Definitely a good reference.

I managed to sneak one in myself, with the help of Darren Wright. Together with his friend Gus, they made thermites popular for hobby motor ignition. We looked and there wasn't much published on it, so I pitched it to my advisor and it all worked out. Here's the paper.

Any ignition system must be carefully sized based on energy output and gas production. Check out, e.g., the pellet ignition system in CTI motors—they've thought that one through carefully, and the results speak for themselves.
Click to expand...

Looks like a nice paper. You should upload it to research gate or the archive sever so we can read it.
 
I have been told that the ping pong balls have a burn inhibitor in them (I still use it), A good nitro cellulose lacquer is the way to go.


TA
 
Tell that to this guy:

[video=youtube;Vw7psWrzHH8]https://www.youtube.com/watch?v=Vw7psWrzHH8[/video]
 
thobin said:
I have been told that the ping pong balls have a burn inhibitor in them (I still use it), A good nitro cellulose lacquer is the way to go.


TA
Click to expand...

I can not confirm that all ping pong balls are flammable, but I can confirm that they are still made of nitrocellulose and will burn. I bought some last week at walmart and they still form a lacquer and burn.
 
Cut a PP ball open and light it with a match. If NC based, it will burn completely. Otherwise, try another brand.
 
Just an idea... do you HAVE to have pyrogen to fire BP charges, or is just the bridgewire enough sufficient?
 
bp is pretty sensitive, but I'd have a bit of pyrogen just in case the grains aren't in contact with the bridgewire... the bridgewire alone can light it but the grain must be touching the bridgewire. If you are using thin gauge nichrome wire (less than 40 gauge) then you want to have a sensitive pyrogen (chlorate based) because the heat output from those thin wires are not going to be very high.
 
cavecentral said:
Cut a PP ball open and light it with a match. If NC based, it will burn completely. Otherwise, try another brand.
Click to expand...

I just ordered some NC Lacquer from Firefox, but I have to go do some shopping tomorrow and will try to swing by a couple places that have Ping Pong Balls. If I can get a couple of different brands I'll take notes and Video and report back with my findings.
Easy enough to light them on fire, and sounds like fun. It would likely be helpful to know exactly which brands use the good formula.
I have been hesitant to bother trying the Balls because I would feel silly if I cut some up and put them in Acetone and nothing happens. Then I've just wasted money and acetone.
 
I think pingpong balls have to be made of NC because the materials have certain properties, and there are strict regulations as to the bounce and weight and size of the balls. (just like nearly all balls used in every sports have strict rules on weight, bounce, etc.)
 
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taiwanluthiers said:
I think pingpong balls have to be made of NC because the materials have certain properties, and there are strict regulations as to the bounce and weight and size of the balls. (just like nearly all balls used in every sports have strict rules on weight, bounce, etc.)
Click to expand...

But apparently some of them are not. There was a thread here awhile back where someone put the chopped up balls in the Acetone and just ended up with chopped up ping pong balls in acetone even after a couple of days.
 
I don't know, but I'm willing to bet they are not regulation pingpong balls. NC bounces in a certain way that other plastics can't replicate, and they have to weight exactly 2.8 grams with a diameter of 40mm.

Cut one open and note the odor. It should smell like camphor. If it doesn't, it's not NC. Camphor is used as plasticizers for celluloid.
 
cerving said:
Just an idea... do you HAVE to have pyrogen to fire BP charges, or is just the bridgewire enough sufficient?
Click to expand...

I used just a bridge wire - actually an ematch blank to ignite a small BP charge as a demo. I would not trust in along in a rocket.
 
taiwanluthiers said:
I don't know, but I'm willing to bet they are not regulation pingpong balls. NC bounces in a certain way that other plastics can't replicate, and they have to weight exactly 2.8 grams with a diameter of 40mm.

Cut one open and note the odor. It should smell like camphor. If it doesn't, it's not NC. Camphor is used as plasticizers for celluloid.
Click to expand...

Cheap stuff for kids doesn't have to be regulation. Mine were good, but I seen numerous warnings not all are along with the suggested burn test. Do not remember the sources of this info.
 
TopRamen said:
But apparently some of them are not. There was a thread here awhile back where someone put the chopped up balls in the Acetone and just ended up with chopped up ping pong balls in acetone even after a couple of days.
Click to expand...

I have never had this experience. I alway buy official tournament grade ping pong balls. They can be bought cheap by the hundreds.
 
cerving said:
Just an idea... do you HAVE to have pyrogen to fire BP charges, or is just the bridgewire enough sufficient?
Click to expand...

Yes, you can just use the bridgewire. That is how the xmas bulb setup works. The bear filament is used. You could use a nichrome bridge wire too.

I would NOT recommend the commercial match heads as a source if you are going to use just the bridge wire. That is too small and too short of wire to consistently light the powder . I tried them dipped in a finely ground BP and nitrocellulose lacquer and all of them burned the bridge wire but none of them ignited the BP.

I use 34ga nichrome wire with a short wrap between the two copper wires so I have about 1/16" long bridge. I dip those in the ground BP and lacquer mix and they work great. I have not flow any of these, but at a couple of cents each, they are much cheaper when ground testing then the $1 each "lighters". They are much more dependable then the commercial matchheads and pyro mix I bought, even for ground testing.
 
I got these Ping Pong Balls at Walmart today. They smell of Camphor when cut, and are apparently, judging by my test, the right kind.
They are Eastpoint Brand, made in China. They were like $9 for 36.

PingPongNitroCellulose 001.jpg

[video=youtube;lZjvoQAhiDY]https://www.youtube.com/watch?v=lZjvoQAhiDY&feature=youtu.be[/video]
 
Igniter chips are designed to work with very sensitive chlorate based pyrogen. It is too small to light anything else... They will light bp IF the grain is in direct contact with the bridgewire.
 
I made NC Lacquer today with the Ping Pong Balls. It was just as easy as anything, and it only took a little bit of stirring and adding a little more Acetone to make it fully dissolved. I used a Ball Canning Jar similar to what I've seen in many instructional videos to mix it and now to store it.
I feel like I have obviously spent money unnecessarily by ordering some from Firefox, but oh well, live and learn.
It only took about 10-12 Minutes to fully dissolve 3.75 balls. It would have been 4 balls but for the two tiny pieces that I used to test, one of which was in the video I posted.


NC Lacquer 002.jpg

ETA: I let it sit overnight to dissolve completely, and now it has what appears to be the perfect consistency according to what I've seen done.
 
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I used to buy NC Lacquer. Now I only buy the flexible type. It is good for coating powdery item to stop them from breaking up.
 
Does anybody use PP lacquer to make ematches? I used to, but my success rate went way up when I started using a better grade of NC lacquer.

For you reloaders out there, any of the smokeless powders can be dissolved in acetone to make a true NC lacquer. The double base powders make the best product :wink:

Kevin
 
Nessalco said:
Does anybody use PP lacquer to make ematches? I used to, but my success rate went way up when I started using a better grade of NC lacquer.

For you reloaders out there, any of the smokeless powders can be dissolved in acetone to make a true NC lacquer. The double base powders make the best product :wink:

Kevin
Click to expand...

It can done. I don't recommend it. Spent 3 years off and on messing with it and I couldn't find consistent blanks. I already had a nice shear
for PC boards and made my own blanks. Instructions are out there. Wire gauge can be critical. The chems are not as forgiving as
those for igniter dip. I tried an ematch kit 6 years ago and it dorked my MAD unit. Homemade matches take alot of testing to be sure they
consistently fire. With the alternatives available, I no longer bother. I never flew my own ematches even though I was getting 100% success from the last test batch. Believe it or not, but reliability improved by letting them "age" for a month or more. Kurt
 

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