MJG/Electricmatch starters

[Antares JS]

Newbie to these electric matches, I'm a little overwhelmed by all I've read and I'm hoping for a simple answer.

1. Does it make sense to use these MJG conductive match wires for igniting composite C, D, E, F, G Aerotech motors (enerjet, etc.)? https://electricmatch.com/rocketry/see/45/6/conductive-match-wire-

2. If so, what do I dip them in?

3. If not, then what?

I'm currently using the MGJ electric matches with great success for black powder engines and since I'm about to place an order for more of those, now is a good time to ask.

Thank you very much.

PS I'm really hoping I don't get too many contradictory answers!

The composite motors you are asking about include igniters. I don't see any reason you would need separate igniters except for just having a couple of spares on hand, in which case I would suggest turning to Wildman or Quickburst for extra igniters that are good for composite motors.

 

[JLP1]

MJG developed the firewires (blue and white wire) as a non regulated alternative to the orange wire e-matches that are highly regulated in the pyrotechnics industry. Folks who participate in pyro as a hobby have a hard time getting the e-matches because they require a license and proper storage facilities. That's why they have different color wire so that they can be identified as the non pyrogen version. Now you can find the orange wire e-matches all over ebay (they come mostly from china) and if you read the descriptions they will sort of dance all around as to what they really are. You can order them and you can receive them but in the process you may also receive a visit from US Customs and BATF. It's the luck of the draw some packages get inspected but most don't. Do You Feel Lucky? Now the firewires were never meant to be used for motor igniters they work fine to fire the charges in duel deploy setups and they work great in pyro shells and other devices but as it's been pointed out the head is to big to fit directly into most motors plus the fire is not quite hot enough for composite type fuel.

So in a nut shell orange wire regulated.
Blue and white non regulated can be purchased by anybody.
Blue and white great for BP in duel deploy but not so hot for composite.

Now there will be folks who will say "I've been buying orange e-matches for years" never had a problem. And that's true but it's like playing poker

 

[Jmhepworth]

I use the MJG ematches for two things—ejection charges for dual deploy and lighting the sustainer in a two stage rocket. Lighting the sustainer with the igniter that comes with the motor generally won‘t work because there isn’t enough juice (voltage or amperage or whatever). Using the MJG ematch to start the sustainer motor requires some kind of enhancement. My tried and true method is to put a pyrodex pellet at the top of the motor when I build it.

 

[markg]

I use the MJG ematches for two things—ejection charges for dual deploy and lighting the sustainer in a two stage rocket. Lighting the sustainer with the igniter that comes with the motor generally won‘t work because there isn’t enough juice (voltage or amperage or whatever). Using the MJG ematch to start the sustainer motor requires some kind of enhancement. My tried and true method is to put a pyrodex pellet at the top of the motor when I build it.

I second this - exactly what I do as well. I vary the size of the pellet depending on the motor. 38mm usually about 1/3 or 1/2 pellet, 54mm and bigger gets a full pellet

 

[cwbullet]

I second this - exactly what I do as well. I vary the size of the pellet depending on the motor. 38mm usually about 1/3 or 1/2 pellet, 54mm and bigger gets a full pellet

You can also use a sliver of Blue Thunder propellant.

 

[rcktnut]

Now there will be folks who will say "I've been buying orange e-matches for years" never had a problem. And that's true but it's like playing poker

I don't think there is much to worry about as long as you're a good boy using them. Any color wires can get you in trouble if used in a nefarious way.

 

[DirkTheDaring]

The composite motors you are asking about include igniters. I don't see any reason you would need separate igniters except for just having a couple of spares on hand, in which case I would suggest turning to Wildman or Quickburst for extra igniters that are good for composite motors.

Because things go wrong and buying extra igniters is expensive and making your own seems like a low cost way to have spares. Maybe you've never inserted an igniter less than perfectly, but I certainly have. This is particularly true for E, F, and G composite engines. Have you priced igniters recently?

The other reason is that they are less than perfect and when it comes to clusters, I want closer to perfect. I've read enough to believe that it's possible to make your own igniters that have a higher reliability than off the shelf igniters. Will the first ones I make be better? Of course not, but I think I can get there.

 

[davidb123]

Because things go wrong and buying extra igniters is expensive and making your own seems like a low cost way to have spares. Maybe you've never inserted an igniter less than perfectly, but I certainly have. This is particularly true for E, F, and G composite engines. Have you priced igniters recently?

The other reason is that they are less than perfect and when it comes to clusters, I want closer to perfect. I've read enough to believe that it's possible to make your own igniters that have a higher reliability than off the shelf igniters. Will the first ones I make be better? Of course not, but I think I can get there.

You can certainly make your own igniter blanks and pyrogen to try to save money in the long run. I make igniters for small (A-E) composite motors with 30 gauge lead wire and 36-38 gauge nichrome. I fold ~20 ft of the lead wire in half, clamp one end, and spin the other on a drill to get it twisted. Then I follow this procedure generally, and this is another useful guide. Be careful and and test the resistance of each completed blank. I do the same procedure for bigger motors, but I will use 26-24 gauge wire and solder instead of crimping.

For pyrogen, you can't do much better than ProCast. You can certainly make pyrogen yourself, and some searching on the forum will get you started. But if you want a no-fuss solution, ProCast is the way to go.

One last tip is for small RMS motors: paint a little pyrogen on the top of the grain and let dry before assembly. This is often used for staging to ensure ignition, but I also recommend it for normal flights. And always lightly sand the oxidation from the interior of the grain as well!

 

[kjhambrick]

<<snip>> But if you want a no-fuss solution, ProCast is the way to go.

One last tip is for small RMS motors: paint a little pyrogen on the top of the grain and let dry before assembly. This is often used for staging to ensure ignition, but I also recommend it for normal flights. And always lightly sand the oxidation from the interior of the grain as well!

All --

I've got a small diameter round rat-tail file to try next time it seems safe (*) fly an old motor but how do Y'All lightly sand your cores ?

Thanks

-- kjh

(*) safe as in reduced chance of a brush fire due to a land-shark

 

[DirkTheDaring]

You can certainly make your own igniter blanks and pyrogen to try to save money in the long run. I make igniters for small (A-E) composite motors with 30 gauge lead wire and 36-38 gauge nichrome. I fold ~20 ft of the lead wire in half, clamp one end, and spin the other on a drill to get it twisted. Then I follow this procedure generally, and this is another useful guide. Be careful and and test the resistance of each completed blank. I do the same procedure for bigger motors, but I will use 26-24 gauge wire and solder instead of crimping.

For pyrogen, you can't do much better than ProCast. You can certainly make pyrogen yourself, and some searching on the forum will get you started. But if you want a no-fuss solution, ProCast is the way to go.

One last tip is for small RMS motors: paint a little pyrogen on the top of the grain and let dry before assembly. This is often used for staging to ensure ignition, but I also recommend it for normal flights. And always lightly sand the oxidation from the interior of the grain as well!

Thank you. I appreciate the specific information. I was hoping to buy pre-made igniters and then dip them, rather than winding the nichrome myself (as a first step). Which brings me back to my first question, are these appropriate for at least the larger engines, once dipped? https://electricmatch.com/rocketry/see/45/6/conductive-match-wire-

And if not, do you have a specific kind that you would recommend? (Although I understand you're not using these, but I gotta start somewhere).

Thank you again.

 

[davidb123]

All --

I've got a small diameter round rat-tail file to try next time it seems safe (*) fly an old motor but how do Y'All lightly sand your cores ?

Thanks

-- kjh

(*) safe as in reduced chance of a brush fire due to a land-shark

That should work fine if it fits in the grain. Rolled up sandpaper also works. My advice is to take a little bit evenly off of the surface - enough so you can see the change in color and surface texture, but not so much as to change the grain geometry.

 

[davidb123]

Thank you. I appreciate the specific information. I was hoping to buy pre-made igniters and then dip them, rather than winding the nichrome myself (as a first step). Which brings me back to my first question, are these appropriate for at least the larger engines, once dipped? https://electricmatch.com/rocketry/see/45/6/conductive-match-wire-

And if not, do you have a specific kind that you would recommend? (Although I understand you're not using these, but I gotta start somewhere).

Thank you again.

Those are ematch blanks and are too wide to fit in the nozzles of low and mid power motors. I think the best place to start with pre-made blanks is Rocketflite. They have good pyrogens too. You can save a lot more money in the long run if you make the blanks and pyrogen yourself, but it is of course more effort.

Feel free to DM me if you have further questions about making igniters since this is somewhat off topic from the thread.

 

[kjhambrick]

Thanks davidb123

I tried the rolled up sandpaper but it was a tad clumsy for me.

But OTOH, I can control the round, rat-tail file pretty well.

I WILL watch that I don't bork the core geometry and symmetry and I will also weigh the grains before and after to get an idea what I changed.

But this won't be happening on a flying motor at an AARG launch until the crops are in and we move from Apache Pass to Hutto and there is less chance of a brush fire.

I'll be buying all my motors from Harry the Motor Man until then

-- kjh

 

[bad_idea]

I'll be buying all my motors from Harry the Motor Man until then

To that point, you'll be glad to know that Harry's magic bus was repaired within a day of its last calamity. Check with him in advance about July though. World Championships are taking over the normal AARG launch date, and while I've heard there may be a launch later in the month, it might conflict with his schedule.

 

[kjhambrick]

Thanks for the info Stephen.

I didn't know the story about Harry's magic bus ...

After a little snooping, I 'found' Harry and his website ( Motorman Rocketry ) and reached him via email and he is planning to attend the rescheduled July AARG Launch

-- kjh

p.s. I didn't know you were a local, bad_idea ... I'll seek you out and introduce myself next time though you may remember me as the June L1 candidate who couldn't lite his H128

 

[WILDMANRS]

MJG developed the firewires (blue and white wire) as a non regulated alternative to the orange wire e-matches that are highly regulated in the pyrotechnics industry. Folks who participate in pyro as a hobby have a hard time getting the e-matches because they require a license and proper storage facilities. That's why they have different color wire so that they can be identified as the non pyrogen version. Now you can find the orange wire e-matches all over ebay (they come mostly from china) and if you read the descriptions they will sort of dance all around as to what they really are. You can order them and you can receive them but in the process you may also receive a visit from US Customs and BATF. It's the luck of the draw some packages get inspected but most don't. Do You Feel Lucky? Now the firewires were never meant to be used for motor igniters they work fine to fire the charges in duel deploy setups and they work great in pyro shells and other devices but as it's been pointed out the head is to big to fit directly into most motors plus the fire is not quite hot enough for composite type fuel.

So in a nut shell orange wire regulated.
Blue and white non regulated can be purchased by anybody.
Blue and white great for BP in duel deploy but not so hot for composite.

Now there will be folks who will say "I've been buying orange e-matches for years" never had a problem. And that's true but it's like playing poker

Some of what you are saying is true but some is not .
I have had several conversations with the BATFe on this subject and it does not matter what color wire you are using .
The BAtfe enforces the laws they do not make them.
Ematches and electric igniters are regulated per the explosives act .
There is no description of what an ematch or igniter is in the explosives act only the words .
if it is called and ematch or an igniter it is regulated. this is why Estes and Aerotech have changed the name of thier lighters.
The reason they call them firewire is so they wont be regulated, and they are not because they are called firewires. it has nothing to do with the composition or the color.

 

[kjhambrick]

Some of what you are saying is true but some is not .
I have had several conversations with the BATFe on this subject and it does not matter what color wire you are using .
The BAtfe enforces the laws they do not make them.
Ematches and electric igniters are regulated per the explosives act .
There is no description of what an ematch or igniter is in the explosives act only the words .
if it is called and ematch or an igniter it is regulated. this is why Estes and Aerotech have changed the name of thier lighters.
The reason they call them firewire is so they wont be regulated, and they are not because they are called firewires. it has nothing to do with the composition or the color.

Wow ! Our tax dollars at work against us again ...

I suppose I'll have to stop using the I-word and the EM-word from now on.

That'll take some practice for an old geezer like me.

Thanks for the info WILDMANRS.

-- kjh

 

[cwbullet]

Blue and white non regulated can be purchased by anybody.
Blue and white great for BP in duel deploy but not so hot for composite.

They Firewire is not hot enough for composites alone. The Firewire will light a compsoite motor with the addition of am additional dip, Pyrodex, or a Blue Thunder sliver.

 

[bad_idea]

Thanks for the info Stephen.

I didn't know the story about Harry's magic bus ...

After a little snooping, I 'found' Harry and his website ( Motorman Rocketry ) and reached him via email and he is planning to attend the rescheduled July AARG Launch

-- kjh

p.s. I didn't know you were a local, bad_idea ... I'll seek you out and introduce myself next time though you may remember me as the June L1 candidate who couldn't lite his H128

Yes, the magic bus broke down about fifteen miles from Apache Pass in June. I picked up a few motors from Harry beside the road and delivered them for him, but unfortunately his usual cornucopia of propellant delights didn't make it to the field that day.

I'm actually up in DFW, but I was down for the June launch and am hoping to start attending AARG launches fairly regularly now that my build/rebuild rate is gradually easing ahead of my crash rate and I have more rockets to fly. I have a bad memory for both names and faces, but I do recall several motors that didn't want to light. I'll let you know if I make it down in July. Always enjoy meeting people in person that I know from the forum.

 

[Rocketjunkie]

Some of what you are saying is true but some is not .
I have had several conversations with the BATFe on this subject and it does not matter what color wire you are using .
The BAtfe enforces the laws they do not make them.
Ematches and electric igniters are regulated per the explosives act .
There is no description of what an ematch or igniter is in the explosives act only the words .
if it is called and ematch or an igniter it is regulated. this is why Estes and Aerotech have changed the name of thier lighters.
The reason they call them firewire is so they wont be regulated, and they are not because they are called firewires. it has nothing to do with the composition or the color.

The FireWires have the same performance specs as the J-Teks. MJG worked with ATF to reformulate the pyrogen to eliminate regulated materials so they are truly unregulated. Like, J-Teks, they will light BP and can be dipped for lighting composites. Legal FireWires MUST have the blue and white wires. The BP starters also have the same specs as FireWires, just a smaller head.

 

[DirkTheDaring]

Those are ematch blanks and are too wide to fit in the nozzles of low and mid power motors. I think the best place to start with pre-made blanks is Rocketflite. They have good pyrogens too. You can save a lot more money in the long run if you make the blanks and pyrogen yourself, but it is of course more effort.

Feel free to DM me if you have further questions about making igniters since this is somewhat off topic from the thread.

Thank you!

 

[DirkTheDaring]

I just exchanged email with MJG and they confirm that these igniters are not appropriate for composite engines. Black powder only.

I will look at rockeflite.

Thank you to everyone who replied and helped me.

 

[David Bachelder]

You'll need a conductive pyrogen formula. What you linked to are only a piece of double-sided circuit board with wires soldered on. There's nothing there to provide the heat to get an igniter going (like nichrome or carbon fibers). I would *not* use them in low power BP motors. They're too large as provided, and will only get bigger with pyrogen (dip). There are better choices for BP motors.

The reply above is correct, but it gets a little more complicated. I've been working with Jeff at MJG trying to get a reliable conductive mix to use with his chips. This is something I promised him and have not delivered. I've known Jeff quite sometime now. I think of him as a good friend and as a dependable supplier for my business.

My efforts have shown that not only do you need continuity, you also need a mix that is highly sensitive. I'm able to get conductivity without a problem. Its the sensitivity that remains a problem. On top of that you will need reliability. I can reach a 70 or 80 percent success rate, but frankly that's not good enough. It wouldn't do Jeff or I any good to offer a product with a low success rate.

Reaching sensitivity offers other problems. If you create a mix that's sensitive enough, you might come up with a mix that has excessive shipping hurdles. Meaning it could be impossible to ship in an economical manor.

I do however recommend dipping e-matches in the ProCast, its very reliable. Great for Clusters, AirStarts, and ground.

If any user has any questions, please contact me as follows.
email: info@ quickburst.net
Phone: 979-373-6601
If you call and I don't answer, be sure to leave a message, I assume all callers that refuse to leave a message are people I don't need to talk to anyway.

Disclaimer:
This is not meant to be an advertisement, please don't take it that way.

 

[tfish]

Some of what you are saying is true but some is not .
I have had several conversations with the BATFe on this subject and it does not matter what color wire you are using .
The BAtfe enforces the laws they do not make them.
Ematches and electric igniters are regulated per the explosives act .
There is no description of what an ematch or igniter is in the explosives act only the words .
if it is called and ematch or an igniter it is regulated. this is why Estes and Aerotech have changed the name of thier lighters.
The reason they call them firewire is so they wont be regulated, and they are not because they are called firewires. it has nothing to do with the composition or the color.

I get it now!

So, the ones on ebay are called "copper wire" makes them legal too!

cool....

Tony

 

[JLP1]

Never said the color of the wire had anything to do with the regulation or the non regulation of the firewires. What I said was that the firewires were done in blue and white so that they could be easily distinguished from the regulated orange ematches in the field. Also I will disagree with the statement that BATF only enforces the law they have a lot of input along with CPSC, NFPA, and other agencies in developing and writing the laws that govern materials of this nature. I have found over the years (especially in pyrotechnics) that 5 different people can talk to the BATF rep and all 5 people will walk away with a slightly different understanding of what the rep said (human nature at work). I just started getting notices from some of my vendors that the firewires are becoming more available again which is very good for the industry. We've had almost 100% reliability with them in our displays and the few failures we have had were usually human error or mechanical damage. Again I speak from the pyro side of the river and not the rocket side but I have seen others use them in their rockets with excellent results.

 

[Banzai88]

..... 5 different people can talk to the BATF rep and all 5 people will walk away with a slightly different understanding of what the rep said (human nature at work).

To be fair, in other venues that that alphabet agency has under it's umbrella.......that single .gov rep may also have a loooooooooong history of telling (and often putting into writing) opinions to those 5 different people 5 distinctly different and often mutually exclusive things.....so it's NOT nearly that black and white very often. Worst agency EVER to work with, especially regarding FFLs, so I wouldn't trust them to have a valid opinion on whether water was wet or if poop stank, and likely no 2 folks in the same field office would agree at the same moment in time. Been there, done that, got the citations and notices of suspected violations......and the apology letters!

Maybe the 'E' part of the office has their mess together? I wouldn't bet the farm on it.

 

[tbonerocketeer]

The ATF regulates items by law. You can call it whatever you want but if it functions as a controlled item, it is controlled. Maybe we should call dynamite a big banger. Think ATF will say its not regulated? The name changing game does not make it legal but sending the actual composition to them to test does if they deem it non explosive.

 

[cwbullet]

The ATF regulates items by law. You can call it whatever you want but if it functions as a controlled item, it is controlled. May we should call dynamite a big banger. Think ATF will say its not regulated? The name changing game does not make it legal but sendingt the actual composition to them to test does if they deem it non explosive.

I suspect a name change will only result in temporary confusion until they figure out the "scam" name.

 

[mtnmanak]

I am unclear why there is confusion about this. MJG spells it out in plain English on their website:

Attention for The only ATF non-regulated initiator on the market. Don't be fooled, the safety explosives act of 2003 regulated all igniters. After many samples and conversations with the ATF, we are proud to announce that we have a non regulated product. These were made specifically for rocketry, law enforcement, and consumer fireworks. Per our patent and ATF agreement, they are only available with a Blue and white lead wire. * Orders less than a case will ship US Mail, without insurance, and can take 2 weeks to deliver. They ship Parcel post. there is not tracking, even though you will get a #. It will only show you when it departs our local facility, and when it arrives to your local facility. It does not update along the way like priority mail. As a special permit is needed to ship these via US Mail, returns are not accepted. Please be sure of your order, and do not place an order if it is time sensitive.

They have a patent that ATF recognizes is not regulated and they agreed to only produce them in blue and white so there was no confusion. The color is only pertinent in the fact that MJG has an agreement with ATF to differentiate their product and the name is only relevant because, as per their agreement with the ATF, it is not an "igniter". Doesn't seem confusing to me...

Now, if you are buying things off of Ebay, I guess the risk is up to you.

 

[cwbullet]

Now, if you are buying things off of Ebay, I guess the risk is up to you.

They might go after a guy selling them in the US, but they certainly are not going to arrest a guy in China.