[RocketsNW] IGNITERS

[Scott Berfield]

I've done some experimenting wth Cu thermite and have had a hard time getting it to light. I also finf the dry powder mix awkward to deal with. Too bad it is even harder to light if you use a binder.

I have had really good results using a strips of propellant in igniters. Do a standard setup with shooting wire and wrap two strips of blue thunder with the nichrome - 4 or 5 wraps. Then dip in dark flash to prime and then a nice sparky pyrogen.


-----Original Message-----
From: Mfreptiles at aol.com [mailto:Mfreptiles at aol.com]
Sent: Thursday, April 9, 2009 05:12 PM
To: scott at scottsrockets.com, lawndart.robert at gmail.com, bphlat234 at comcast.net,
rockets at rocketsnw.com, jhadv at pacifier.com
Subject: Re: [RocketsNW] IGNITERS

Except in high humidity it will not initiate unless you replace a small portion of al with mg. Myself and the late Alex M. had the same problem at a cold, damp, spring Brothers launch. Mike F. In a message dated 4/9/2009 5:09:22 P.M. Pacific Daylight Time, scott at scottsrockets.com writes: One word... Copper oxide thermite. Wait, that's three words. Cheap, easy, safe, and works VERY well. Crap, that's seven words, unless these words count, then....never mind. Scott T. Bowers www.scottsrockets.com -----Original Message----- From: rockets-bounces at rocketsnw.com [mailto:rockets-bounces at rocketsnw.com] On Behalf Of Robert Krausert Sent: Thursday, April 09, 2009 3:39 PM To: Gary Harris; rockets at rocketsnw.com; Paul Bogdanich Subject: Re: [RocketsNW] IGNITERS I'd like an opinion here. For 38mm and larger, I've been more successful adding a sliver of Blue Thunder to the ignitor. I simply take a grain of BT, and cut a chunk out and use kite string to secure it to the ignitor head. When I've done this, all motors have started fine. My question is, is adding the BT sliver really helping, or would the large ignitor with pyrogen have been fine alone? Curious. Cheers, Robert ----- Original Message ----- From: "Gary Harris" To: ; "Paul Bogdanich" Sent: Thursday, April 09, 2009 3:06 PM Subject: Re: [RocketsNW] IGNITERS > Paul gave me one of his low-pressure and high heat producing thermite > ignitors mentioned below last october to use in a 11-year old J350. It > started up instantly like an Estes motor. > > Gary Harris > > ----- Original Message ----- > From: "Paul Bogdanich" > To: > Sent: Tuesday, April 07, 2009 12:30 PM > Subject: [RocketsNW] IGNITERS > > >> At 11:27 AM 4/7/2009 -0700, you wrote: "...there's likely no basis for >> regulating an ignitor which is used with a non-explosive device. >> Igniters >> packaged with unregulated motors (and replacement ignitors) were >> themselves >> considered unregulated." >> >> I think you said it in your e-mail when you said igniters, "packaged with >> unregulated motors..." The only problem being that said devices are, in >> the opinion of some, very low performance devices so much so as to be >> just >> barely functional. People of this opinion would point to all the >> chuffing >> and recycling one witnesses at almost any launch. Such devices (total >> calorific output of less than .5 kcal) probably do qualify as "motor >> starters" and may very well be able to be unregulated. I certainly don't >> see why they should be regulated as some safety match heads with the >> pyrogen scraped off, dissolved in a solvent and cast around a bridge wire >> would produce more heat. We don't regulate books of matches do we? >> I myself, however, would like to see an "igniter" that can add between 6 >> and 10 calories per cc of propellant surface, generate enough gas >> products >> to put the motor interior at >= 200 psi but < 400 psi, totally burn well >> within 100 ms, and achieve a flux rate of greater than 100 cal/cm2/sec >> for >> a 38mm motor (this last metric can change with motor size and propellant >> characteristics). That's an igniter and I think you're still going to >> need >> a permit for those. A NASA Standard would be an example of such an >> igniter >> albeit for a much larger motor than a 38mm. >> Whether or not a thermite (where such term includes thermate and >> thermalite) based igniters should be restricted is an open question as >> those lie between the two classes of devices already mentioned (they >> generally do not pre-pressure the motor nor create a shock wave). I >> suspect however, that the BATFE position would be that thermite, thermate >> and thermalite are definitely regulated as they are included in the >> definitions section of the statute whereas APCP was not. >> >> _______________________________________________ >> Rockets mailing list >> Rockets at rocketsnw.com >> http://mx1.blastzone.com/mailman/listinfo/rockets >> > > _______________________________________________ > Rockets mailing list > Rockets at rocketsnw.com > http://mx1.blastzone.com/mailman/listinfo/rockets > _______________________________________________ Rockets mailing list Rockets at rocketsnw.com http://mx1.blastzone.com/mailman/listinfo/rockets _______________________________________________ Rockets mailing list Rockets at rocketsnw.com http://mx1.blastzone.com/mailman/listinfo/rockets **************New Deals on Dell Netbooks – Now starting at $299 (A HREF=http://pr.atwola.com/promoclk/100126575x1220635155x1201407495/aol?redir=http:%2F %2Fad.doubleclick.net%2Fclk%3B213771973%3B35379628%3Bw)

-------------- next part --------------
I've done some experimenting wth Cu thermite and have had a hard time getting it to light. I also finf the dry powder mix awkward to deal with. Too bad it is even harder to light if you use a binder.
 
I have had really good results using a strips of propellant in igniters. Do a standard setup with shooting wire and wrap two strips of blue thunder with the nichrome - 4 or 5 wraps. Then dip in dark flash to prime and then a nice sparky pyrogen.
 
 
-----Original Message-----
From:
Mfreptiles at aol.com [mailto:Mfreptiles at aol.com]
Sent:
Thursday, April 9, 2009 05:12 PM
To:
scott at scottsrockets.com, lawndart.robert at gmail.com, bphlat234 at comcast.net,
rockets at rocketsnw.com, jhadv at pacifier.com
Subject:
Re: [RocketsNW] IGNITERS
Except in high humidity it will not initiate unless you replace a small portion of al with mg. Myself and the late Alex M. had the same problem at a cold, damp, spring Brothers launch. Mike F. In a message dated 4/9/2009 5:09:22 P.M. Pacific Daylight Time, scott at scottsrockets.com writes: One word... Copper oxide thermite. Wait, that's three words. Cheap, easy, safe, and works VERY well. Crap, that's seven words, unless these words count, then....never mind. Scott T. Bowers www.scottsrockets.com -----Original Message----- From: rockets-bounces at rocketsnw.com [mailto:rockets-bounces at rocketsnw.com] On Behalf Of Robert Krausert Sent: Thursday, April 09, 2009 3:39 PM To: Gary Harris; rockets at rocketsnw.com; Paul Bogdanich Subject: Re: [RocketsNW] IGNITERS I'd like an opinion here. For 38mm and larger, I've been more successful adding a sliver of Blue Thunder to the ignitor. I simply take a grain of BT, and cut a chunk out and use kite string to secure it to the ignitor head. When I've done this, all motors have started fine. My question is, is adding the BT sliver really helping, or would the large ignitor with pyrogen have been fine alone? Curious. Cheers, Robert ----- Original Message ----- From: "Gary Harris"
To:
; "Paul Bogdanich"
Sent: Thursday, April 09, 2009 3:06 PM Subject: Re: [RocketsNW] IGNITERS > Paul gave me one of his low-pressure and high heat producing thermite > ignitors mentioned below last october to use in a 11-year old J350. It > started up instantly like an Estes motor. > > Gary Harris > > ----- Original Message ----- > From: "Paul Bogdanich"
> To:
> Sent: Tuesday, April 07, 2009 12:30 PM > Subject: [RocketsNW] IGNITERS > > >> At 11:27 AM 4/7/2009 -0700, you wrote: "...there's likely no basis for >> regulating an ignitor which is used with a non-explosive device. >> Igniters >> packaged with unregulated motors (and replacement ignitors) were >> themselves >> considered unregulated." >> >> I think you said it in your e-mail when you said igniters, "packaged with >> unregulated motors..." The only problem being that said devices are, in >> the opinion of some, very low performance devices so much so as to be >> just >> barely functional. People of this opinion would point to all the >> chuffing >> and recycling one witnesses at almost any launch. Such devices (total >> calorific output of less than .5 kcal) probably do qualify as "motor >> starters" and may very well be able to be unregulated. I certainly don't >> see why they should be regulated as some safety match heads with the >> pyrogen scraped off, dissolved in a solvent and cast around a bridge wire >> would produce more heat. We don't regulate books of matches do we? >> I myself, however, would like to see an "igniter" that can add between 6 >> and 10 calories per cc of propellant surface, generate enough gas >> products >> to put the motor interior at >= 200 psi but < 400 psi, totally burn well >> within 100 ms, and achieve a flux rate of greater than 100 cal/cm2/sec >> for >> a 38mm motor (this last metric can change with motor size and propellant >> characteristics). That's an igniter and I think you're still going to >> need >> a permit for those. A NASA Standard would be an example of such an >> igniter >> albeit for a much larger motor than a 38mm. >> Whether or not a thermite (where such term includes thermate and >> thermalite) based igniters should be restricted is an open question as >> those lie between the two classes of devices already mentioned (they >> generally do not pre-pressure the motor nor create a shock wave). I >> suspect however, that the BATFE position would be that thermite, thermate >> and thermalite are definitely regulated as they are included in the >> definitions section of the statute whereas APCP was not. >> >> _______________________________________________ >> Rockets mailing list >> Rockets at rocketsnw.com >> http://mx1.blastzone.com/mailman/listinfo/rockets >> > > _______________________________________________ > Rockets mailing list > Rockets at rocketsnw.com > http://mx1.blastzone.com/mailman/listinfo/rockets > _______________________________________________ Rockets mailing list Rockets at rocketsnw.com http://mx1.blastzone.com/mailman/listinfo/rockets _______________________________________________ Rockets mailing list Rockets at rocketsnw.com http://mx1.blastzone.com/mailman/listinfo/rockets **************New Deals on Dell Netbooks – Now starting at $299 (A HREF=http://pr.atwola.com/promoclk/100126575x1220635155x1201407495/aol?redir=http:%2F %2Fad.doubleclick.net%2Fclk%3B213771973%3B35379628%3Bw)