Diy E-match or igniter

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If you search for "pyrotechnic primes" you might have better luck. You can also get a pretty good idea of the formulation of many commercial dip kits from the MSDS (gotta list all flammable metals and oxidizers) or from the name. For example, H3 is a fireworking formulation by Shimuzu, also used as a dip by some (why???)--chlorate and charcoal only--chlorates don't play well with sulfur and what does BP contain...? As Kurt indicated above, some comps are much more sensitive to friction than others. Chlorate-based notoriously so. Nitrate-based not so much, but generally less aggressive burning, too. Perc-based in the middle. In general... Fuels: Mg too reactive and unstable; Al common and cheap; MgAl sparky hot but a little more expensive; Boron great but very expensive; Zirconium the same & hard to source; charcoal cheap but relatively cooler burning--fine for BP but insufficient for APCP without supplemental metals.
 
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"Primers" are not needed to make motor starters (igniters). There's no reason to make primer compositions and take the risk. Primers are sensitive & explosive by definition.

The igniter pyrogens we typically use (from motor manufacturers, dip kits, etc.) are referred to as "first fires", not primers. Most of the igniter dip formulas you find online are close to one of the standard first-fire formulas.

Bulk pryogens for large professional rocket motors are usually in pellet form, held in a perforated metal basket. The initiator at the core of those ignition systems contains a first fire and/or a primer. But, the main requirement is that they take a large current to get started, not sensitive to static discharge. Boron-based pyrogens are the most commonly used professionally, less sensitive, and most efficient at heat & gas production.

Specific formulas are only allowed in the restricted research section here. The boron-based supplies are not that expensive considering how little is needed for a typical consumer rocket motor. About 1/3rd is needed compared to other pyrogens.
 
"Primers" are not needed to make motor starters (igniters). There's no reason to make primer compositions and take the risk. Primers are sensitive & explosive by definition.

The igniter pyrogens we typically use (from motor manufacturers, dip kits, etc.) are referred to as "first fires", not primers. Most of the igniter dip formulas you find online are close to one of the standard first-fire formulas.

Bulk pryogens for large professional rocket motors are usually in pellet form, held in a perforated metal basket. The initiator at the core of those ignition systems contains a first fire and/or a primer. But, the main requirement is that they take a large current to get started, not sensitive to static discharge. Boron-based pyrogens are the most commonly used professionally, less sensitive, and most efficient at heat & gas production.

Specific formulas are only allowed in the restricted research section here. The boron-based supplies are not that expensive considering how little is needed for a typical consumer rocket motor. About 1/3rd is needed compared to other pyrogens.
Primers or primes, as in powdered comps (usually dry, sometimes in slurries) used to to coat or cover and ignite more difficult-to-ignite fireworking stars or propellants, not to initiate detonation as in firearm cartridge primers using shock-sensitive fulminates/azides etc. That would be unnecessary. There is no utility or need to initiate detonation with a primary explosive in fireworking, except perhaps for some fx tasks. Which is why I specified "fireworks primers". Probably coulda left the "r" out of primes, though. And nobody's providing recipes here.
 
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Primers or primes, as in powdered comps (usually dry, sometimes in slurries) used to to coat or cover and ignite more difficult-to-ignite fireworking stars or propellants, not to initiate detonation as in firearm cartridge primers using shock-sensitive fulminates/azides etc. That would be unnecessary. There is no utility or need to initiate detonation with a primary explosive in fireworking, except perhaps for some fx tasks. Which is why I specified "fireworks primers". Probably coulda left the "r" out of primes, though. And nobody's providing recipes here.
Again, there is no need for any primes or primers in consumer or amateur rocketry, whatever the original purpose may be.

Standard e-matches/squibs use a low-temperature, sensitive mixture lacquered on the heads. Not required for rocketry but it's what is manufactured by professionals for professional use. The ATF lists it as an explosive composition, requiring a permit. When used on an e-match head, the device becomes a regulated "igniter", per ATF terminology. MJG has an ematch-like product which does not use a primer composition (trade secret). Their "Firewire Initiator" is not considered a regulated device by the ATF (it's not an e-match or squib, although it uses a similar blank head).

Regarding the original question: DIY e-match, NO, but "initiators" and "motor starters" (traditional rocket igniters), YES. Easiest way is to get a dip kit (Quickburst.net etc). For mixing from scratch, see the Research forum here.
 
You simply do not store completed friction sensitive comps in screwcap jars. Ever. It's fine to use a plastic bottle for mixing slurrys for dipping that are relatively passivated in suspension (even in a flammable solvent), bur avoid screwcaps. Dried comp on the threads and a little friction are not a good combination. And glass containers of any type. Storage is unwise when it is such a simple thing to quickly whip up a new batch of most any pyrogen formulation that you might employ, including expensive kit components if you weigh and use only part of a kit at one time. But unfortunately many people ignore those basic safety tidbits, to their own detriment.

And for anybody thinking to experiment with pyrogens for the first time, even if you have a decent chemistry background (recommended), it is absolutely essential to know which chemicals simply do not play nice with others (think chlorates + sulfur in any form, as one example...).
Very true, but stuff like this is worth mention on this list anyway. Some readers don't know squat about what makes for a sensitive mixture. Some don't know that there are different types of sensitivity: friction, impact, pressure, spark, heat, etc. And that a sensitive mixture isn't necessarily sensitive in all these ways.

I recall a very-well-known rocketnut who has participated in some pretty advanced projects. Said individual had made some kind of composition that burnt too easily so he/she added an ingredient to slow down the burn. Unfortunately the additive is known to increase sensitivity and burn rate in most compositions...

Best -- Terry
 
I know we are talking 2 different things here guys. Im talking motor ignition and deployment charges. Thanks for all of the info, so much experience here!
 
I agree with previous posts, don't mess with ejection charge igniters (ematches) at all. Buy commercial. I tried that, but way too much trouble for way too inconsistent results! The best I came us with were xmas light bulbs broken, soldered, and glued in tubes. Way too much trouble!

I make EX motors so I need "motor starters" A rocketeer from NC gave me a simple easy formula years ago that I use with prfesser nichrome wraps in post #11 (I've modified them slightly). I've yet to find a commercial starter that works better, maybe faster, but not better. It's a simples substitute of the BP formula and everything can be bought at Walmart. Less than $0.03 a starter. $0.10 if you have to buy the starter wire. I use them for H to M motors. I would encourage anyone interested to try making starters. It's fun and easy and if you don't include your "hobby" time, very economical.

Unless you are making starters for AT Hobbyline motors, those small ones can get frustrating in a hurry and make you look forward to using copperheads!
 
Very true, but stuff like this is worth mention on this list anyway. Some readers don't know squat about what makes for a sensitive mixture. Some don't know that there are different types of sensitivity: friction, impact, pressure, spark, heat, etc. And that a sensitive mixture isn't necessarily sensitive in all these ways.

I recall a very-well-known rocketnut who has participated in some pretty advanced projects. Said individual had made some kind of composition that burnt too easily so he/she added an ingredient to slow down the burn. Unfortunately the additive is known to increase sensitivity and burn rate in most compositions...

Best -- Terry
My guess is that ingredient begins with an "S", which works ok for slowing black powder and making smokey delay charges (like Estes does) but not so good with certain other comps, particularly chlorates and widely available H3 dips (chlorate + C }...
 
You can get commercial, unregulated ematches at https://electricmatch.com/rocketry/see/36/6/mjg-firewire-initiater
Not worth the reliability issues of homemade as the commercial ones are less than $1 each.

The first one is naked. The second has an oxidizer, a sulfur containing compound, and a lacquer.
Last is one with the previous and a single dip in magnalium and red gum. Depending on how much
oomph you need, to paraphrase Pink Floyd, you can keep on dipping. Been making them for
a long time, ground and air, and have never had a failure. For air I double them.
Shout out to Seminole Wire and Cable.

Joe O
matches.JPG
 
The first one is naked. The second has an oxidizer, a sulfur containing compound, and a lacquer.
Last is one with the previous and a single dip in magnalium and red gum. Depending on how much
oomph you need, to paraphrase Pink Floyd, you can keep on dipping. Been making them for
a long time, ground and air, and have never had a failure. For air I double them.
Shout out to Seminole Wire and Cable.

Joe O

The typical self-made e-match costs about $60-85 for 100. You can buy the premade one for $60 for 80. I have made them and I can't justify making them on my own. That is less than $1 each. My time is worth more than that.
 
Thinking back to the first model rocket I flew (and promptly lost) in the early '60s, all Centuri provided for an ignitor was a bare piece of light gauge nichrome wire with instructions to wrap it around the tip of a ball point pen tip, and secure the coil in place with a little piece of wadded up kleenix. Probably still all that's needed for black powder motors.
 
The typical self-made e-match costs about $60-85 for 100. You can buy the premade one for $60 for 80. I have made them and I can't justify making them on my own. That is less than $1 each. My time is worth more than that.
Don't care. It's fun.
I keep a LARGE building running.
Little stuphe is cool.
 
Don't care. It's fun.
I keep a LARGE building running.
Little stuphe is cool.

I am not criticizing you. Do what you want or your wallet will allow. I am making sure everyone reading the forum and following this thread knows it is not financially beneficial to make your own matches unless you are doing large volume and making the blanks yourself.
 
Copy that.
Whatever one does, do it safely.
The wife says that I have "analysis paralysis" and it takes me forever
to figure something out. In no way have I done anything large volume.
 
The typical self-made e-match costs about $60-85 for 100. You can buy the premade one for $60 for 80. I have made them and I can't justify making them on my own. That is less than $1 each. My time is worth more than that.
And if one doesn't mind dealing directly with Asian shipping, 100 ematches with 30 cm leads (all that's needed for most rocketry uses) runs about $30-40.

Best -- Terry
 
Thinking back to the first model rocket I flew (and promptly lost) in the early '60s, all Centuri provided for an ignitor was a bare piece of light gauge nichrome wire with instructions to wrap it around the tip of a ball point pen tip, and secure the coil in place with a little piece of wadded up kleenix. Probably still all that's needed for black powder motors.

Not for Clusters !

BTW - That "Coil Tip" might be VERY good at holding a "blob" of Pyrogen in place !

Dave F.
 
And if one doesn't mind dealing directly with Asian shipping, 100 ematches with 30 cm leads (all that's needed for most rocketry uses) runs about $30-40.

Best -- Terry
Pretty close, T. The 11-inchers (approx 30 cm) are currently selling for $29/100 including shipping (possibly in a first class padded envelope with no indication of flammable contents (!)) shipped from their US "stash" in 3-5 days, or $22/100 including shipping sent from China in 3 weeks or so, in a cardboard box. I'm not sure what the customs declaration states, but they might describe their wireless firing modules as "controller for LED lighting", tsk tsk.... Plus local taxes that Ebay now collects. These haven't been an enforcement priority by the ABCs so far, but that could change at any time.
 
Thought about painting my mailbox with that a few years ago when we had some shitheads running around bashing mailboxes. Didn't do it but boy was it tempting. :eek:
Had too look that chemical up......all I can says the mailman would have been pissed if he got there first....🤣
 
Thinking back to the first model rocket I flew (and promptly lost) in the early '60s, all Centuri provided for an ignitor was a bare piece of light gauge nichrome wire with instructions to wrap it around the tip of a ball point pen tip, and secure the coil in place with a little piece of wadded up kleenix. Probably still all that's needed for black powder motors.
Yes nichrome still works perfectly fine for BP motors, if you have enough battery power. I just measured a piece of nichrome I have left over from 50+ years ago and it measures 32 gage. Back then we tried using whatever batteries we could scrounge up and had limited success, whenever possible we just used a car battery.

Now I have a couple of 24mm composite motors I want to launch and not rely on the old copperhead igniters so I need to make a few "starters". I don't want to get into complicated chemicals. I probably need to buy more nichrome. I can get smokeless powder and I already have acetone.

The link further up the thread for e-matches says they are the only one that is unregulated which I think means something you can buy without hazmat shipping. Actual starters for composite motors seem to cost $5-7 EACH and would require the additional cost of hazmat shipping. I'm sure that my 24mm motors didn't cost that much when I bought them which is why I'm looking into making a few myself.
 
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Has anyone tried to use high voltage to light an ap motor?
I have a Falcon heavy model that I built during lockdown last year.
It uses E Engines for the boosters , and I'm looking st a commercially packaged ap engine for the main stage.
Getting yhem to all go at the same time on the test bench is a problem,lol.
It's lofting a camera and dual deployment electronics, so I dont expect too much altitude.
I have a few ccfl,based HV supplies; they strike at over10kv.
 
Yes nichrome still works perfectly fine for BP motors, if you have enough battery power. I just measured a piece of nichrome I have left over from 50+ years ago and it measures 32 gage. Back then we tried using whatever batteries we could scrounge up and had limited success, whenever possible we just used a car battery.

Now I have a couple of 24mm composite motors I want to launch and not rely on the old copperhead igniters so I need to make a few "starters". I don't want to get into complicated chemicals. I probably need to buy more nichrome. I can get smokeless powder and I already have acetone.

The link further up the thread for e-matches says they are the only one that is unregulated which I think means something you can buy without hazmat shipping. Actual starters for composite motors seem to cost $5-7 EACH and would require the additional cost of hazmat shipping. I'm sure that my 24mm motors didn't cost that much when I bought them which is why I'm looking into making a few myself.
https://electricmatch.com/rocketry/see/23/6/bp-rocket-starters
 
Yes nichrome still works perfectly fine for BP motors, if you have enough battery power. I just measured a piece of nichrome I have left over from 50+ years ago and it measures 32 gage. Back then we tried using whatever batteries we could scrounge up and had limited success, whenever possible we just used a car battery.

Now I have a couple of 24mm composite motors I want to launch and not rely on the old copperhead igniters so I need to make a few "starters". I don't want to get into complicated chemicals. I probably need to buy more nichrome. I can get smokeless powder and I already have acetone.

The link further up the thread for e-matches says they are the only one that is unregulated which I think means something you can buy without hazmat shipping. Actual starters for composite motors seem to cost $5-7 EACH and would require the additional cost of hazmat shipping. I'm sure that my 24mm motors didn't cost that much when I bought them which is why I'm looking into making a few myself.
https://www.frankumperformance.com/starters-and-initiators
 
Has anyone tried to use high voltage to light an ap motor?
I have a Falcon heavy model that I built during lockdown last year.
It uses E Engines for the boosters , and I'm looking st a commercially packaged ap engine for the main stage.
Getting yhem to all go at the same time on the test bench is a problem,lol.
It's lofting a camera and dual deployment electronics, so I dont expect too much altitude.
I have a few ccfl,based HV supplies; they strike at over10kv.
I think mixing parallel BP motors with a central AP motor is actually a question on the Level 2 test as something that can pose a safety issue.
One way to get the BP parallel motors lit is to use onboard electronics to light them based on the acceleration of the rocket when the central AP motor lights. You must use an AP motor with enough thrust to keep it going straight up even if your boosters fail to light. You must not rely on a mix of BP and AP to provide sufficient lift.
You should be able to use HV ignition, but I doubt it’ll light the AP any faster. HPR flyers have used many techniques to get AP motors lit quickly for clusters. Some work well and some add an element of excitement.
 
One way to get the BP parallel motors lit is to use onboard electronics to light them based on the acceleration of the rocket
This seems like a reasonable method. In watching composite motors I've noted that some of them reach thrust in less than 1 second, maybe 1/2 second, but others seem to work on it for 2-3 seconds. Maybe the difference has to do with the type of igniter. If you are clustering I would think you want the fastest ignition possible and even then the BP motors still probably start quicker.
 
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