Looking for comments on "Igniterman" conductive primer ignitors

George,

I use a similar kit offered by firefox. It works really well.

Mike Fisher Binder Design

George, I have used Igniterman stuff extensively and I guess the best thing to say is, they are as good as the maker. if you do your job, they will work every time. Get sloppy and well, they don't work nearly so well. For the smaller motors, they are simply awesome using wire wrap. If the solution dries out (and it does) I just ad some acetone and it comes back as good as ever. My Pratt firing unit as well as my Unicon unit have no trouble lighting clusters of as many as 6. So, that's my $.02 worth. BTW, who has the kits these days? My understand was that they were no being produced.

I'd agree with all of that. If you take the time to get the correct gap and make sure the conductors are _parallel_ conductors, they are incredibly reliable. If you don't take the time, they still work pretty well, but for clustering, I would definitely take the time to make them as consistent as possible, and then compare the resistance of the finished igniters and use matched pairs.

I've had my kit for 3 or 4 years and made well over a hundred wire wrap igniters, I've probably given away as many as I've used myself. The stuff always dries out, but works just fine with the addition of acetone.

George, I've used Igniterman igniters to light F10 and E6 (and C10) as well as Aerotech and Ellis Mountain G,H,I, and J motors. They work. I've used them for staging also, fired by a 9V battery. If you go with them, ground test a few to get the hang of it.

I've recently tried Quickburst, s> I'm considering getting an "Igniterman" construction kit to make up ignitors.

Yeah, but how do they work on saucers?

Doug

Conductive primer igniters work well. I sold the Igniterman kits for years, and customers have been very happy with them; in fact, I can't remember a single complaint.

However, if the head cracks you no longer have a complete circuit. Recently I've been making up solderless-bridgewire igniters with a wire wrapping tool I made that gives me very repeatable results. It's possible to make these wrapped igniters with wire-wrap wire for the leads, resulting in a very skinny igniter; I use them mostly in 18mm RMS motors. If I were you, I would look at making up some solderless bridgewire igniters out of wire wrap wire.

See you at NARAM, eh?

Publish a website describing it?

You can make your own conductive primer using nitrocellulose lacquer purchased from a hobby store and graphite powder purchased from a hardware store. You can then use whatever pyrogen you like on top of the primer. I've made igniters with a conductive primer for small AeroTech motors (D21, D13, etc.) using 30 gauge wire from Radio Shack, and igniters for large motors.

Dean

Well, I'm going to be the dissenting voice here. I've used the Igniterman kit for several years, and the igniters I've made for the larger motors (H-J) work great...but I've never been able to get the smaller igniters (for F-G motors) to work at all.

I've used the smallest wire I could find (I think it was 30 ga.), double checked the gap, followed the instructions....but of the 20 or so of that size that I made, NONE lit.

Since other people HAVE used them for small motors (E6 size!), I know it must be something I'm doing wrong....what's the secret?

Ric T. snipped-for-privacy@sct.org

Never flew the G12 but noticed the G25 is pretty chuff happy... Is the G12 a blue thunder end burner?

Impedance matching your ignitors would be SOP...

Regards, Andy

What happened when you fired them? Nothing at all?

Did you measure the resistance before using? If so, what was it?

Here's something that I discovered. I made my own primer from nitrocellulose lacquer and graphite. Acetone is the solvent in nitrocellulose lacquer. The pyrogen normally used acetone as the solvent. The pyrogen had dried out and I used some MEK and acetone to get it back into solution. I dipped the wires in the primer, dried them and checked them with an Ohm meter. They looked good. I dipped them into the pyrogen, dried them and checked a few with the Ohm meter. Resistance had jumped from 10-20 Ohms to around 100 or more. I figure the MEK in the pyrogen broke the connection between wire and primer because this problem did not happen when I did not use MEK. I now use a pyrogen that uses lacquer thinner as the solvent and have not had a repeat of the problem.

Dean

I've used them for 18mm RMS reloads, where there is very little room. The wire I use is 30 awg wire wrapping wire. I'm not sure there's any secret! Here's what I do, but I'm pretty sure it's all in the instructions:

Cut wire to length

Strip wire at both ends, about 2-3mm at the 'hot' end, the other end isn't important. I use a proper wire wrap stripping tool.

twist wires together, I like to use two colours, and I twist them between my fingers. This just adds a bit of mechanical strength.

Add sufficient acetone to conductive primer to make a thinish paste, mix well as you add it to avoid over doing it. If I put too much in, I just stand the bottle outside for an hour or so, and the excess acetone evaporates.

Dip all igniters in conductive primer. As I dip each igniter I ensure the conductors are parallel. I don't usually measure the gap, just judge it by eye, getting them as close as I can without touching.

Let them dry, takes a few minutes.

If I'm making them to keep for a while, I'll dip them in sealant next, if I'll going to use them the next day, I don't usually bother.

Add sufficient acetone to pyrogen primer to make a thinnish paste, mix well as you add it to avoid over doing it. It's harder to get a consistent mix with the pyrogen than the conductive primer. This the hardest bit IMHO.

Dip igniters in pyrogen. I might dip twice, but usually only once if I want very thin igniters, which is why it's important to get a good pyrogen consistency.

Leave to dry and then dip in sealant once again.

That's it! I usually use 12v to ignite them.

As someone else said, they dipped ends can crack, so I usually store them by putting about half a dozen into a discarded copperhead tube. The tails can hang out, but the tube protects the heads.

Hope that helps!

Strip the wire, squish them together (depends on your wire), hold it up to the light of the TV to make sure they're not touching and dip. You can get a pretty consistent with resistance. Consistency of the dip is the key, but you'll have to play. One second it will all just run off, the next it's a glob. Recommend stirring every or every other dip if you strip n dip. You could strip a bunch of wire prior to dipping, but stripping just before dipping avoids additional oxidation on the wire. Shooter's wire is easier than dealing with 'CAT' cables and doesn't have issues to look out for when purchasing.

Make a few, test them for resistance and function after they've dried (wait a day). Once you're making them consistently, don't bother checking them until you select them at the field. Good Ohm meter recommended.

Joel. phx

Yeah, maybe the consistency of the pyrogen was my problem. I already do everything else you mention. I'll have to try it again paying more attention to the pyrogen.

Thanks.

Ric T.

Nice to see you at LDRS Doug... wish we had more time to talk, But with only a handful on the BRS committee we were kept busy the whole week. We got home late Tuesday night and I slept on and off most of Wednesday - VERY unusual for me; I am usually like the Energizer Bunny. It was a blast, especially the EX days. And it is worth mentioning that without the visiting volunteers we could never have managed.

As I state in an earlier posting - I am using both dipped and nichrome bridgewire igniters. Both seem to work well for me. After some further thought I am going to stick my neck out and say that I think my preference is going to be for the bridgwire igniters. They take a little bit more work than simply dipping but I think that one can get a fairly consistent result, especially if one is careful about trying to have only 1/4 to 1/2 inch of exposed and non-shorted bridgwire. I am about to try building them with #28 wirewrap twisted pair and they should be incredibly skinny. Presently building them with #24/#26 twisted pair and they are pretty skinny but not as skinny as some of the commercial jobs I have used.

Igniters, after some considerable research, are an art in and of themselves. A science and an art. Ray Halm's "superigniter' course at NYPOWER a couple of years ago was very informative.... but dealt with the top end of the igniter range... for lighting big M's, etc. Ray wrapped a couple of slivers of Blue Thunder to a dipped e-match (Oxral or Daveyfire, I dont' recall). This 'superigniter' lit an M motor in a blink - I don't recall ever seeing an M come up to full pressure faster. I seem to recall something about scraping the inside of the uppermost propellant slug to roughen the surface and expose fresh propellant as well. I also seem to recall someone suggesting painting the core of the uppermost propellant slug with pyrogen. Like I say... it's probably time for someone to write a definitive article on igniters for hobby rocketry

-- it is a science and an art all on its own.

Heck, just maintaining the right consistency of the Igniterman primer dip is an art.

Doug... always nice to see you and hope we bump into you again soon.

Murray Lampert TRA 08855 BRS

Both FireStar and Magnelite electric match are in business.

Greg Dyben Rocketflite/Magnelite

Oh my gosh! He's going from a single motor in the ET to a pair of motors in the SRBs for his scale RC shuttle! Now all he needs is some FX motors for the SSMEs.

This will be one cool flight!

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

But I feel confident in the wire-wrap type for the twin G12 cluster I'm doing for NARAM, which is the main thing this was about.