First Scratch Ignitors

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cat5 would work good, but its not that cheap. however...i believe i had a LOT laying around here somewhere. if i find it...(i mean a LOT, my dad is in the computer surplus business, and he had a LOT, an entire box full, probably a couple hundred yards) then i'll let you know. i'd give it to you, as long as you pay shipping.
 
I have used Cat 5 before with the twisted pairs. It workd fine for me. I think locally I can get Cat 5 for about 7 cents a foot. Also, if you want solid speaker wire I know Radio Shack has some 24ga solid speaker wire. It is $3 for 75 feet.


Edward
 
I noticed that sometimes when I ignite my igniters, there is a pop and a chunk of the pyrogen breaks off without igniting anything else. Any ideas? I am using 38 guage nichrome and strands of cat 5 cable (which is super cheap on e-bay if you are still needing igniter wire.)

-Chris
 
What kind of pyrogen are you using?

This usually happens when ignitors are "double dipped". Rather than burning and sparking they tend to pop.
 
I am using a pyrogen mix found online at sparksrocketry.com.

I do double dip my igniters to thicken them up a bit. Sometimes it works, sometimes it breaks off. I will try just singel dipping and see what happens.

-Chris
 
I have a question. Where can you get the nichrome wire? I tried the links earlier in this thread, but apparently they are too old and don't work. I searched the McMaster Carr website for nichrome, but all they had was cloth. Any ideas?
Thanks,
Reed
 
Originally posted by Reed Goodwin
I have a question. Where can you get the nichrome wire? I tried the links earlier in this thread, but apparently they are too old and don't work. I searched the McMaster Carr website for nichrome, but all they had was cloth. Any ideas?
Thanks,
Reed

I just picked up some from this guy on eBay. $3.50 for 60 feet of 36 gauge. Probably not the best price, but reasonable.

WW
 
Originally posted by Reed Goodwin
I have a question. Where can you get the nichrome wire? I tried the links earlier in this thread, but apparently they are too old and don't work. I searched the McMaster Carr website for nichrome, but all they had was cloth. Any ideas?
Thanks,
Reed

Do a search for nickel chromium wire on the mcmaster carr site and you should hit the jackpot.
 
I bought a spool of 36 guage nichrome for $75. It contained 24,000 feet of wire on it. I sold it on e-bay for a while (until the price dropped really low and wasn't profitable) and made about $900 from that. But if *anyone* wants 50 feet I'll ship it to you - I'm never going to use the remaining 17,000 feet I have.

Edward
 
i made my first igniters today, after having become frustrated with copperhead igniters. I purchased the Cyclone RC electric match production set from firefox on Thursday and it arrived on Monday. the kit came with 50' of wire, 50 *element* chips, and some small containers of chemicals.

after preparing the chemicals for use, i cut the wires to length, stripped 1/8" from the end of each one, then tinned the bare ends with solder. the *chips* get wedged between the tinned wire-ends and it just took a brief tap with the soldering iron to bond each lead securely.

the rest of it is just dipping the chips into the pyrogen slurry then setting aside to dry for a couple hours before dipping in the nitrocellulose laquer sealer and setting aside to dry.

I tested one, and it lit easily and burned like a sparkler for 2 to 3 seconds!

very nice!

igniters.jpg
 
If you don't want to buy nichrome, you can get cheap, thin, steel wire from any craft store. It's in the flower arranging section. The thin wire goes red-hot and melts very fast when hit with 12 volts and a normal amount of current. Molten steel will light most pyrogens, in my experience.

The downside of this is that the steel might corrode inside the ignitor. I wouldn't keep the ignitors around more than a year.

urbanek
 
Originally posted by edwardw
But if *anyone* wants 50 feet I'll ship it to you - I'm never going to use the remaining 17,000 feet I have.

Can you quote a price on 100 feet? Or 500 feet?
 
Hey Edward,

I'll buy a couple of hundred feet from you. Just send me a PM with a price.

(You don't really have 17,000 feet do you?!?!?)

Thanks,
John
 
Yes, I really have 17,000 feet. The spool came with 24,000 feet on it. PM me your address' and I'll roll some and send it off to you.

Edward
 
Well I just went by the local Lowes and found that they sell CAT5E for about $25 per 500 feet which is about 5 cents/foot. I am definitely going to get some as soon as I get a check cashed, I think. Will these ignitors fit into a 29mm reload?
Thanks,
Reed
 
It will depend on your wire wrap technique and the thickness of the pyrogen coating.

The G64 might be a little trouble with it's small nozzle, but I would think the H128 and H180 shouldn't be a problem.

The 'longer' (in length, more grains) reloads will also have larger nozzles, especially BT or Redline, so you may have better luck with these.
 
I used CAT5 wires in a G80, G35 and G64 with no problem. I made sure I folded the wires at the top so they were all in the same plane. When assembling a reloadable, I build the ignitor in rather than insert it afterwards.
 
Originally posted by rbeckey
I used CAT5 wires in a G80, G35 and G64 with no problem...When assembling a reloadable, I build the ignitor in rather than insert it afterwards.
Is it just easier that way? Might there be the risk of the ignitor getting stuck?
Reed
 
The wires are not the problem, it is the pyrogen at the end that is a little too thick and hard to push in without damaging it. After ignition, that is no longer a factor.
 
I cut up some CAT 5 cable to use, and was wondering where I could find directions for making a pyrogen/pyrogen-like mixture? Either using the Ping Pong balls and such or others would be helpful. I don't want to buy a pyrogen kit either. Thanks!

PS: the black mark on the tape measure in the photo is the 1' mark.
 
ive seen alot of homemade ignitors and looking at the dip on the ends iam just curious on how would you go about fixing it so it would fit MOST composite motors like AT motors?
 
Let them dry on there side not hanging down. Becasue if you let it dry hanging down it well form a ball on the end.
 
I forgot to mention: no BP either, as I can't get that legally, I don't think (and my dad won't let me).
 
I used Pyrodex. I should have ground it into a fine powder, but I didn't. You certainly should do that.
Reed
 
Hmm if your dad won't buy BP then he probably won't want to buy you the chemicals you need to make your own pyrogen either. It might be best to just buy commercial igniters until you are old enough to buy this stuff yourself. Or get a pyrogen kit.
 
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