Dear Manufacturers: Make the Igniter Leads for BP Motors Slightly Longer

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brockrwood

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Dear Estes and Quest and Manufacturers of Igniters for Black Powder Motors: Make the leads for the igniters slightly longer. Another inch or so should do it. That way, I can clip my igniter clips to the ends of the longer leads and get them out of the way of the exhaust blast of the motor. That will save a lot of time in cleaning and scraping dirty igniter clips.
 
Dear Estes and Quest and Manufacturers of Igniters for Black Powder Motors: Make the leads for the igniters slightly longer. Another inch or so should do it. That way, I can clip my igniter clips to the ends of the longer leads and get them out of the way of the exhaust blast of the motor. That will save a lot of time in cleaning and scraping dirty igniter clips.
Omg Brockwood,
I just started a thread about unsuccessful Ignitions. I didn't know what I was doing wrong. It'd be really nice if the leads were longer you'd have a better chance to keep your clips out of the way or possibly shorting out on the blast shroud. I was envisioning a wire 6"-8" or possibly even a foot long. That way you could keep the wires down off the launchpad as well as your clips going to the ignition box. I see other companies make igniters like that but I don't know if they'd fit into an Estes motor. Maybe others in the group have experimented with the other brands. I'd love to know what the other options are. I feel your pain.
Thanks, Dyl
 
Omg Brockwood,
I just started a thread about unsuccessful Ignitions. I didn't know what I was doing wrong. It'd be really nice if the leads were longer you'd have a better chance to keep your clips out of the way or possibly shorting out on the blast shroud. I was envisioning a wire 6"-8" or possibly even a foot long. That way you could keep the wires down off the launchpad as well as your clips going to the ignition box. I see other companies make igniters like that but I don't know if they'd fit into an Estes motor. Maybe others in the group have experimented with the other brands. I'd love to know what the other options are. I feel your pain.
Thanks, Dyl

You could take a standard Estes igniter and attach your own bare wires to it (just splice the wires by twisting them together), but that might be more time and trouble than simply cleaning the igniter clips when they get dirty.
 
I've never had an Estes starter fail since I started gluing BP to them. But back to the original post, yes, solder on some small gauge wire.
I can't recall an Estes igniter failing on me. I have had other ignition problems, occasionally, such as an igniter that I did not insert properly or low battery power in the launch controller.
 
I can't recall an Estes igniter failing on me. I have had other ignition problems, occasionally, such as an igniter that I did not insert properly or low battery power in the launch controller.
You have experience a rare blessing. The new ones without pyrogen that are not ATF-regulated often do not get hot enough to ignite the motor, especially on cold and/or breezy days. The older ones with pyrogen were much more reliable.

The current line of Estes starters are just corn starch over bare nichrome wire.
 
You have experience a rare blessing. The new ones without pyrogen that are not ATF-regulated often do not get hot enough to ignite the motor, especially on cold and/or breezy days. The older ones with pyrogen were much more reliable.

The current line of Estes starters are just corn starch over bare nichrome wire.
You mean the igniters that have that silvery coating on the nichrome wire rather the black coating on the nichrome wire? Is that what you are referring to? If so, is that stuff just corn starch? I have only recently started to see Estes igniters with the silvery coating rather than the black coating.
 
You mean the igniters that have that silvery coating on the nichrome wire rather the black coating on the nichrome wire? Is that what you are referring to? If so, is that stuff just corn starch? I have only recently started to see Estes igniters with the silvery coating rather than the black coating.
Yes. After the ATF decided that Estes starters require HAZMAT, they removed the pyrogen and use (I think) corn starch. Might just be a flammable glue of some kind.
 
Yes. After the ATF decided that Estes starters require HAZMAT, they removed the pyrogen and use (I think) corn starch. Might just be a flammable glue of some kind.
Correct, it's just corn starch and glue. You'd probably get a better flame envelope from glue and crushed up Doritos. But BP doesn't need a super hot fire to ignite it. Suboptimal yet functional, however, for longer core-burning BP motors where you want topside ignition like a composite motor. Cored BP motors are a lot more forgiving than APCP if they get fired up lower down in the core instead of at the very top. The reason you often see them with a fuse hanging out the backside.

Estes hobby "starters" are fine summer weekend igniters for a day at the park using small Estes BP motors. But for anything else I soak that junk off and replace with a properly burning comp. Hot water removes it easily. Or build them completely anew, which is not at all difficult--would never pay almost a buck for an Estes "starter" if I exhausted the ones that come packaged with the motors. Haven't tried the new & "improved" Startech starters yet. I'm sure they're very impressive.
 
Yes. After the ATF decided that Estes starters require HAZMAT, they removed the pyrogen and use (I think) corn starch. Might just be a flammable glue of some kind.

Ironically, I found the new type of igniters in a package of Estes black powder model rocket motors. Estes always includes igniters in each package of motors. It seems to me that Estes could include the old, black pyrogen type of igniters in the packages of black powder motors since the igniters are sealed up in the same package that has to be shipped as HAZMAT anyway. Aren't Estes black powder motors a HAZMAT item that must be shipped as a HAZMAT item? What difference would it make if the igniters in the same package as the motors that are also HAZMAT?

It has been a long time since I bought a package of igniters "stand alone" in a package of just igniters.
 
Correct, it's just corn starch and glue. You'd probably get a better flame envelope from glue and crushed up Doritos. But BP doesn't need a super hot fire to ignite it. Suboptimal yet functional, however, for longer core-burning BP motors where you want topside ignition like a composite motor. Cored BP motors are a lot more forgiving than APCP if they get fired up lower down in the core instead of at the very top. The reason you often see them with a fuse hanging out the backside.

Estes hobby "starters" are fine summer weekend igniters for a day at the park using small Estes BP motors. But for anything else I soak that junk off and replace with a properly burning comp. Hot water removes it easily. Or build them completely anew, which is not at all difficult--would never pay almost a buck for an Estes "starter" if I exhausted the ones that come packaged with the motors. Haven't tried the new & "improved" Startech starters yet. I'm sure they're very impressive.

I have not used any composite motors in my rockets yet as I am still building LPR, Estes type rockets that use black powder motors.

I did find an old package of Estes "E9" black powder motors in my motor collection box. I think I bought it for the Estes Executioner I still need to build. They are huge, heavy monster engines! I see why energy dense, composite motors are used for mid power and high power rocketry. To equal the energy of a composite motor, say an "F", a black powder motor would have to be ridiculously large and heavy.
 
You have experience a rare blessing. The new ones without pyrogen that are not ATF-regulated often do not get hot enough to ignite the motor, especially on cold and/or breezy days. The older ones with pyrogen were much more reliable.

The current line of Estes starters are just corn starch over bare nichrome wire.
Hmm. I need to test out these new type Estes igniters, with no pyrogen, on a cold day. As summer fire bans get more and more common, launching rockets in the winter, when there is no ban, is more and more my best option.

Lessee. The AA alkaline batteries in a typical LPR model rocket launch controller can put out a max of about 1 amp, in short bursts, such as those needed to launch a rocket. Four alkaline AA's (6V at 1 amp for a short period) is about the smallest voltage and current you can use to reliably ignite a black powder motor. The cool thing about the pyrogen on an igniter is that the pyrogen gives you an "electric match". You just need enough electrically created heat to set off the pyrogen. The pyrogen should then set off the rocket motor.

Without a good, sensitive pyrogen on the igniter, you have to feed more current through the nichrome wire, itself, to make it get "white hot" and set off the engine.

I guess I should start using my 12V launch system, with high current batteries, if I am to use the new igniters reliably. I launch two and three BP motor clusters, so I need there to be plenty of current going through the igniters. Cluster rockets depend upon good, powerful ignition systems to make sure all of the engines light and light fast.
 
To equal the energy of a composite motor, say an "F", a black powder motor would have to be ridiculously large and heavy.

It wouldn’t surprise me at all if you know this already, but I understand Estes manufactures black powder F15 motors. 29 mm diameter, 114mm length, which is much bigger than the old E9s or the current E12s. They also offer E16s in that same case, incidentally.

I have yet to fly the 29mm BPs, but one of these days….

But yeah, a black powder F generating upwards of 200N average thrust (one of the Cesaroni composite reloadables does this) would just be impossibly large.
 
You could take a standard Estes igniter and attach your own bare wires to it (just splice the wires by twisting them together), but that might be more time and trouble than simply cleaning the igniter clips when they get dirty.
It was my 1st try at launching a rocket so the clips were shiny and new.
 
But for anything else I soak that junk off and replace with a properly burning comp. Hot water removes it easily.

Have you tried leaving the coating on and just adding quick dip in NC lacquer? Or even painting some "liquid bandage" on top?
 
It wouldn’t surprise me at all if you know this already, but I understand Estes manufactures black powder F15 motors. 29 mm diameter, 114mm length, which is much bigger than the old E9s or the current E12s. They also offer E16s in that same case, incidentally.

I have yet to fly the 29mm BPs, but one of these days….

But yeah, a black powder F generating upwards of 200N average thrust (one of the Cesaroni composite reloadables does this) would just be impossibly large.
BP F motors stop there because the Estes F15's contain 60g BP, which is nearing the 62.5g BP (or APCP) propellant mass per device/reload kit that the DOT considers model rocket motors exempt from explosives regulations (49 CFR regs). And those F15s don't get much more than half the maximum total impulse allowed in the F category (40-80Ns). The F15 total impulse is 49Ns vs the E16's 33Ns. They're like an "E+". And they're big & heavy--an Estes F15 weighs over 100g. It's just the E16 tube (40g w nozzle!) and identical nozzling/coring with a few more increments of BP pressed onto the ends--the thrust curves are almost identical with the F15 having a longer burn. Average thrusts are similar (14-16N) as are peak thrusts at around 26-27N. The smaller E12 has more initial oomph with peak thrust around 33N but average thrust is only around 11N, iirc. The E9s are comparatively anemic but have their uses if you don't happen upon a CATO lot that destroys rockets. I've personally never had an E9 failure (yet), but have had D12 ejection failures.

You can pack way more BP than 60g into a rocket motor--it's done all the time in fireworking. Those motors can get heavy because thick cardboard tubing is necessary to handle the pressing forces needed to consolidate grains, and, perhaps to a lesser extent, to contain the burn. "3-pound" motors are 1" ID, and 6-pounders are 1.5" ID and can hold 250g+ BP. https://www.brianredmond.net/dwilliams/rocket/rocket.html . By federal law, you can ram (or press, if you're really going to drag a press along with you) BP motors and fire them on site, to your heart's content, without an ATF license, but you'd better not run afoul of local/state regs. And without licensing you cannot transport them, hence the "on-site" build restriction. I've heard of folks successfully hand-ramming 1" iD motors, but I stop at 3/4".

But the increasing weight in large BP motors is where the much higher ISP of APCP really shines.
 
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Have you tried leaving the coating on and just adding quick dip in NC lacquer? Or even painting some "liquid bandage" on top?
Thoughtful suggestion, but I can't imagine a real benefit of encasing slightly flammable glue in a hard coating of slightly flammable NC. In it's dense form, NC itself, while it will burn, does not do so vigorously and with a large flame envelope. A hard chunk of solid NC (high nitration status, 13%+) generated from drying lacquer burns about as vigorously as a similar sized matchhead. Maybe even a little slower. Nothing like flashcotton or magician's flashpaper that has a large surface area. This is easily demonstrated.

In recent experimentation, I'm getting even better results with proven pyrogens by reducing the NC content in lacquer suspensions from the commonly used 10%. And some preliminary tests using rubber cements instead of NC lacquer to confer some flexibility and resistance to cracking/flaking seem promising. This isn't really surprising--others have used viton and other flexible (and variably flammable) binders/carriers with good results.
 
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I can't say I've ever felt the need for longer igniter leads with Estes motors. I mean, it couldn't *hurt*. The igniter clips get blown away from the motor very quickly after ignition.

I feel like I should post this again here, for those who didn't see it in the other thread.
 
I can't say I've ever felt the need for longer igniter leads with Estes motors. I mean, it couldn't *hurt*. The igniter clips get blown away from the motor very quickly after ignition.

I feel like I should post this again here, for those who didn't see it in the other thread.

The primary benefit of longer leads is that you can wrap them around the launch clips, ensuring a good circuit.
 
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