Daveyfire e-matches

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llickteig1

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Can anyone tell me the difference between the Daveyfire N28 series e-matches and the N20 series?

InfoCentral has a discussion of e-matches at https://www.info-central.org/recovery_ematches.shtml but doesn't mention the N20.

I have used the N28BR e-matches many times for ejection charges and am primarily interested in whether or not the N20F is suitable for that same purpose?

TIA, --Lance.
 
Hey! I resemble that remark! :p

Davey 28Bs are the standard for igniting black powder. I've never heard of the N20 type fusehead, but if its designation ends in an F, that means it's a special effects fusehead. Translation: burns longer, requires more current (3-4 amps at least). So an N28F or an N20F would more likely be suited to motor ignition than altimeter ejection -- some units may not even be able to fire those matches. You could give em a shot (ground test first! if that doesn't work, you've got a lot of motor igniters ;)), but my advice would be to stick with the 28Bs.

HTH!
 
its my understanding that the NB20 were a "special order " ematch and the FAI Spacemodleing guys used them...... I have maybe 10 of them...they have a smaller "head" than the larger NB28 series....

I saw a post a few months ago were some of the FAI Spacemodleing guys contacted DF about producing more, and they were told no.....
 
N28B All fire current 400 ma, pops. Good for ejection.
N28F All fire current 1000 ma, burns. For motors.
N20F All fire current 1000 ma, for motors. Smaller head than 28 series. There's also a 20B but I haven't used any. The number is bridgewire size in microns.
 
Originally posted by Rocketjunkie
N28B All fire current 400 ma, pops. Good for ejection.
N28F All fire current 1000 ma, burns. For motors.
N20F All fire current 1000 ma, for motors. Smaller head than 28 series. There's also a 20B but I haven't used any. The number is bridgewire size in microns.

I like the idea of using N28B's for everything - dip them in pyrogen for motor ignition... hey, maybe even dip them a wee bit in pyrogen for ejection charges too? Whadya think? That way you don't do what I did when I launched my MiniBBX with CPR. In my haste I grabbed a N28F by mistake - the altimeter wouldn't fire it and my MiniBBX sleeps with the corn now.

I am also looking at using Firestar conductive dip/pyrogen to make my own matches. Must check the current requirements for them.

ML
 
The head of the N28B is to fast to reliably ignite pyrogen, that's the reason why the "F" version is used to be dipped.
To my knowledge 28 or 20 indicates the wire gauge used, normally the N20 should take more current to fire, but this may have been compensated by a changed geometry of the bridge wire.

Juerg
 
Originally posted by Juerg
The head of the N28B is to fast to reliably ignite pyrogen, that's the reason why the "F" version is used to be dipped.
To my knowledge 28 or 20 indicates the wire gauge used, normally the N20 should take more current to fire, but this may have been compensated by a changed geometry of the bridge wire.

Juerg

You might want to talk to the Gates brothers then, dipped 28B's are what they used for their clusters. They work just fine with a good pyrogen.
 
My statement was the "general rule", if one dips a N28B then there will most likely be some disappointment (at least).
I know that with certain preparations N28B's may be used and yes, I'll ask Dirk and Eric some time how they did exactly because the N28F isn't readily available in Europe.

Thanks

Juerg
 
I've been using 28B's with a dip of Magnelite for two years. I switched from F's to B's after Erik said that it worked fine. I have never had one fail. I can only speak for Magnelite. YMMV
 
That's interesting. I did try magnelite but it didn't work for me.
An hints?

Juerg
 
I have seen where some have coated the match too thick or too much, resulting in the match blowing the pyrogen off instead of igniting it. Try a thinner coat of pyrogen and see how that works.

Carl
 
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