Home Made Igniters ??

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plasticpaul

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Okay, I get the idea of a thin wire that will heat upo when current is run through it. I understand the idea of ping-pong balls and acetone. I am wondering about Pyrogen, is this a generic term for an explosive material, is this what I will have when I mix black powder with my ping-pong ball, acetone mix or is it something specific?

Will BP, PP balls and acetone work as an igniter compound when applied to a very thin wire?
 
I don't understand the ping-pong ball/acetone route that is often espoused. Just go by some nitrocellulose lacquer or nitrocellulose fiber from Firefox and make your own. (NC lacquer). They are both non-regulated and non-hazmat materials. You may even find some NC lacquer at Home Depot.
The results will be much better.
 
Pyrogen is a generic term. Whether it will work or not depends on what you are trying to light.
 
whatever you do don't actually use Ping Pong balls! (speaking from experience) the stopped making them out of nitrocellulose a while back. So you WONT get NC laquer. Just buy the powder fomr Fire Fox and mix the acetone and Bp as normal. The mixture works as good as pyrogen :)

thanx, Ben
 
To this day, I've used ping pong balls, graphite powder and acetone to make the NC lacquer and I and others here have used them with 100% efficiency.

For the pyrogen, I believe there are some metal powders involved to give it a real flare. NOT something you want to be grinding with BP in the kitchen. For the ones I make and use, I buy the pyrogen.
 
You can test your ping pong balls by cutting a piece off, putting it in a safe container like an ashtray outside, and lighting it.
 
Originally posted by ben
whatever you do don't actually use Ping Pong balls! (speaking from experience) the stopped making them out of nitrocellulose a while back.
I thought so too, but I lit one a few months back and sure 'nuff, it went "fwoof". It was a recent purchase from Wal-Mart.
 
Originally posted by plasticpaul
Will BP, PP balls and acetone work as an igniter compound when applied to a very thin wire?

I helps to use powdered graphite/powdered iron in the Nitrocellulose lacquer mix. The key is to get one nice strand of steel wire from 00 steel wool between to thicker supporting wire posts then coat the thin steel strand with the Nitrocellulose lacquer. The commercial nitrocellulose lacquer preparations are expensive so I prefer to use ping pong balls dissolved in acetone or lacquer thinner. Walmart still sells the Nitrocellulose ping pong balls and they are not to expensive.

Bruce S. Levison, NAR #69055
 
Originally posted by teflonrocketry1
I helps to use powdered graphite/powdered iron in the Nitrocellulose lacquer mix. The key is to get one nice strand of steel wire from 00 steel wool between to thicker supporting wire posts then coat the thin steel strand with the Nitrocellulose lacquer. The commercial nitrocellulose lacquer preparations are expensive so I prefer to use ping pong balls dissolved in acetone or lacquer thinner. Walmart still sells the Nitrocellulose ping pong balls and they are not to expensive.

Bruce S. Levison, NAR #69055

Agreed on the graphite powder. Using the ping pong balls in acetone alone will not be significantly electrically conductive. Mixing graphite powder in to create the consistency of table syrup will add the conductivity that, as a bonus, lets you gap the wire leads (about the width of a sheet of paper) and not need to solder or attach any wires between them.

CAT 5 scraps from a commercial computer company= $0
8 oz Acetone = ~$0.50
6 pack Wal-Mart ping pong balls = ~$2.00
2 tubes graphite powder from your local Farm & Fleet = ~$2.00

That's a couple hundred LPR ignitors for less than 5 bucks. For APCP, add a pyrogen dip kit for about $20.00 and even if you have to buy your own CAT 5 cable and split it to make paired strands, you're still at less than a quarter per ignitor.
 
Thanks folks this is the kind of info I was looking for. Thwe theories are nice but it is nice to hear from someone who is making them and have the process explained in detail !!! I am thinking that if I make the igniters you have come up with and then dip them in a BP NC mix they should work in my APC motors.
 
I could definitely see this being worthwhile for motors other than BP. But is their any advantage over the Estes igniters for Estes BP motors?

(sorry for the newby question....but despite my years in the hobby I have only used Estes engines except for 2 occasions.)
 
Originally posted by Bohica
I could definitely see this being worthwhile for motors other than BP. But is their any advantage over the Estes igniters for Estes BP motors?

(sorry for the newby question....but despite my years in the hobby I have only used Estes engines except for 2 occasions.)

One advantage is that it make clusters easier to set up. I am building a night launch vehicle that will use 7 estes D engines. Home made ignitors made from cat5 wire simplifies things, in that you can easily twist all the leads together.
 
There are some BP motor igniters out there like this. Some people like doing this for BP motors they plan to cluster because they can get virtually identical resistance to help insure simultaneous ignition of the motors. Beyond that, I see no reason to go through this process for BP motors.
 
Agreed. Clusters are pretty much the only reason to do this with BP motors.
 
I fly both types of motors and I had a few issues with my Estes igniters last weekend especially with my cluster rocket. I am mostly looking for reliable ways to ignite my APC motors.

Here is one of my ideas, tell what you folks think of this plan. Ping-Pong balls disolved in a Solvent we use at work (highly flaimable) for cleaning up glue. To this I plan to add graphite powder and BP. I was wondering though should I twist my Cat 5 wire ends together or gap them? The other bigger question is do you folks think this will even work to ignite my APC motors?

I am also looking at using some of these ideas combined with Christmas lights to make my E-Matches. Perfect Flite has very nice instructions for making the E-matches. I am not sure on the details but i will be using the bulbs with some FFFF BP

One of the guys I work with suggested the old style Cat 3 wire because it is pretty cheap and still readily available.
 
I played around with some of the wire last night by hooking it up to my launch controller. Boy does that wire get hot fast !!!! It started to melt the insulation right off. The Dunce here decided to see just how hot it was so I held on to the bare wire and pushed the button.....Yah it gets HOT !!!!
 
Originally posted by plasticpaul
I played around with some of the wire last night by hooking it up to my launch controller. Boy does that wire get hot fast !!!! It started to melt the insulation right off. The Dunce here decided to see just how hot it was so I held on to the bare wire and pushed the button.....Yah it gets HOT !!!!

Are you married? I ask because I'm just imagining my wife's reaction if I had done that. That's just funny!:D
 
Oh Yah....and I got that reaction. She waqs sitting across the table doing homework with one of the kids. As soon as I did it I realized I should have been doing this kind of experimantation in private !!!
 
During one of my test runs, I accidentally had the clips touching. Within a second, they welded together.
 
I use the hellfire ignitor kit that I got from Just Rockets. I use cat 5 twisted pairs in which the two striped ends (1/4 inch) are side by side (with a slight gap determined by the thin insulation of the wires). I use a dab of CA to hold the ends together and parallel. This is then dipped in the conductive coating and then dipped into a sealer. The conductive coating give a 3 to 10 ohm resistence depending on how close the gapping was. These can be used in black powder rockets as is, or be give a coat of brownish red pyrogen for ap motors. I have not had one fail to ignite. For seriously large engines you can use slivers of blue thunder propellent and coat it with the pyrogen (I saw this done on the Giant Saturn 5 launched at ARG 3).
 
Thanks Terry, You have reassured me that my plan of gapping the wires and dipping them in my "nasty" little mix will work just fine. I may skip the Ping-Pong ball thing and pick up some lacquer. To the lacquer I will add the graphite powder and 4F BP.
 
I understand it might not work but I have faith in my creative destructive intuition. On the other hand, the solvent I brought home from work is very flamamble so maybe I should mix that with the P-P balls.

I do seem to have a certain creative knack and I have looked into some of the kits and I am not hearing of a magic formula of some kind.
 
There's no reason not to try it. If it works, that's great.

I'm sure there are special formulas (maybe not all of them are special), but you don't hear about them because manufacturers don't want to tell you and we are not allowed to post them here.
 
If you are gapping and dipping, I would suggest a 2 stage process--the first stage being conductive primer (your laquer or the ping pong ball/acetone/graphite mix) and, once that dries, then another dip using the mixture with the 4F BP.

Having a grain of the 4F touching both leads (and with that small a gap, it could touch both) could cause variances in resistance.
 
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