Igniter wire

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jj94

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I'm going to go and buy some Quickdip or Magnelite, but then I don't know what type of wire to get. I'm going to get 40 AWG nichrome from Newton's 3rd as my bridge wire, but have no clue of what to get for my leads. The igniters will be used for BP clusters, and 18mm through 29mm AP. What type of wire can I use that will fit through the nozzle and C-slot of the AP motors?
 

quickburst

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I'm going to go and buy some Quickdip or Magnelite, but then I don't know what type of wire to get. I'm going to get 40 AWG nichrome from Newton's 3rd as my bridge wire, but have no clue of what to get for my leads. The igniters will be used for BP clusters, and 18mm through 29mm AP. What type of wire can I use that will fit through the nozzle and C-slot of the AP motors?
Ground start 12 volt igniters, use 30 AWG NiChrome.
Airstart use 36AWG NiChrome.

Developed length of heater coil should be about 1" and resistance around 1 to 2 Ohms.

40 AWG is pretty light, but should work in a pinch.

I think you will like the New QuickDip. A little hotter than the first generation, and a shade easier to light.

Continious improvement, is my goal.
 

kramer714

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just finished dipping some igniters when I saw this thread,

I'm only using my igniters for ground starts. With 6 wraps of 36 AWG nichrome around one of the conductors on the wire, I get around 3 -3.5 ohms resistance. For leads I use Cat5 solid twisted pair. Seems to work for me but I'm wondering if a lower resistance (less wraps) would work 'better'.

Couple of other thoughts / questions / suggestions,

I always cut the leads different lengths, having seen many clips short together on pads, simply making one lead an inch shorter makes this much less likely.

I have never sprayed lacquer on my dipped ends, is there any benefit? what type to use?

I was thinking of storing my igniters in a pvc tube (like you keep welding rods) any chance of setting them off from sliding in PVC?
 

kandsrockets

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You will have no problem with 40ga nichrome wire, I have made hundreds with this and have not had one fail do to 40ga nichrome wire. I have also made airstart igniters with the same nichrome wire.
 

jj94

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Will the pairs of wires found inside a length of Cat5 fit in the C-Slots? That's what I'm so worried about, I would hate for the igniter to get caught in the slot or in the nozzle and cause the motor to overpressurize.
 

RandyM

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For the smaller motors like 18mm and 24mm AP, I use 30ga wirewrap wire that you can get from Radio Shack. I normally use two different colors in case I use them in a cluster. The 40ga nichrome will work great with this. When you get up to the 29mm motors, CAT5 will work fine for most as long as the nozzle is big enough.
 

kramer714

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cat5 BARELY fits in a F20-4W motor, anything larger fits well
 

jj94

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I'm looking at some shooter's wire. What gauge of shooter's wire would be suitable for 29mm?
 

jj94

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Anyone know where I can find cheap 26 gauge?
 

jj94

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I just took a look. They come in 500 ft rolls, which is a lot, but it is pretty cheap when you look at the price per foot that you get. Thanks.
 

BAR0051

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When you go to a club launch, volunteer to clean up around the pads and pick up the used leads there. Just cut off the burnt part and re-use the rest for your leads. I have been doing this and have lots of good lead wires. :)
 

jj94

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Alright, so it's settled. I'll be ordering some Quickdip after TARC ends for my team (if we make it to the finals or not). Now I got to thinking, what if I added some additives to the mix? Aluminum, titanium, or magnesium for some hot sparks? Incorporating small slivers of Blue Thunder propellant into the igniter for a hotter burn (I already put slivers of Blue Thunder in the top of my grains to aid in ignition with copperheads)? Does anyone here add things to their pyrogen?
 

Handeman

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I haven't made many igniters. The ones I did make, I got a magnesium fire starter at a camping store and filed the edges to add magnesium filings to the mix. Made for a hotter flame.

As for copperheads, all I ever do to aid them is to sand the inside of the grains and leave the dust in there. That ignites quick and fires the grains very well.
 

m85476585

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just finished dipping some igniters when I saw this thread,

I'm only using my igniters for ground starts. With 6 wraps of 36 AWG nichrome around one of the conductors on the wire, I get around 3 -3.5 ohms resistance. For leads I use Cat5 solid twisted pair. Seems to work for me but I'm wondering if a lower resistance (less wraps) would work 'better'.

Couple of other thoughts / questions / suggestions,

I always cut the leads different lengths, having seen many clips short together on pads, simply making one lead an inch shorter makes this much less likely.

I have never sprayed lacquer on my dipped ends, is there any benefit? what type to use?

I was thinking of storing my igniters in a pvc tube (like you keep welding rods) any chance of setting them off from sliding in PVC?
Don't quote me on this, but here's what I would do:
Make a few igniters with just nichrome but no pyrogen and hook them up to a launch controller and see what happens. If it barely glows, the resistance is too high/the nichrome is too long. If it suddenly melts/pops with very little heat given off, it might be too short. If the entire wire turns into bright white glowing molten metal at the same time (then probably breaks shortly after), this is probably what you want since the most energy will be put into the pyrogen.

I dip my igniters in Nitrocellulose lacquer. I actually just got some Ping-Pong balls and dissolved them in Acetone, so I'm not sure if it is really nitrocellulose, but a thin layer of it does not interfere with lighting motors, and it protects them from moisture.
 

jj94

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Don't quote me on this, but here's what I would do:
Make a few igniters with just nichrome but no pyrogen and hook them up to a launch controller and see what happens. If it barely glows, the resistance is too high/the nichrome is too long. If it suddenly melts/pops with very little heat given off, it might be too short. If the entire wire turns into bright white glowing molten metal at the same time (then probably breaks shortly after), this is probably what you want since the most energy will be put into the pyrogen.

I dip my igniters in Nitrocellulose lacquer. I actually just got some Ping-Pong balls and dissolved them in Acetone, so I'm not sure if it is really nitrocellulose, but a thin layer of it does not interfere with lighting motors, and it protects them from moisture.
Yup, that's what I was thinking of doing, finding a good length of nichrome that will be the best for me. I'll be using these igniters possibly in AP clusters so I'd like the fastest and most reliable ignition I can get. I'm looking for an igniter that burns hot for maybe two seconds to make sure the propellant ignites and it comes up to pressure quickly.
 

bobkrech

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I dip my igniters in Nitrocellulose lacquer. I actually just got some Ping-Pong balls and dissolved them in Acetone, so I'm not sure if it is really nitrocellulose, but a thin layer of it does not interfere with lighting motors, and it protects them from moisture.
Yes. Ping Pong balls are still made from nitrocellulose, aka gun cotton.

Bob
 

powderburner

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Yes, as Bob stated, they are still made of nitrocellulose,
IF
you buy the higher-quality, "name brand" products at a sporting goods store.

If you find "cheapo" PPBs in a place like the dollar stores (or even Wmart), there is an increasing chance these days that you will get some cheap plastic substitute. They don't bounce the same or "play" the same. If you cut a narrow strip and light it with a match, they don't burn the same either. The differences are fairly obvious but you do need to check.
 

m85476585

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I got the cheapest ones I could find. I did try burning one, but I haven't seen a "real" nitrocellulose ping-pong ball burn, so I don't know if they are the same. It did burn quickly, though it could have been faster too. Either way, the ones I used work well for my igniters.
 

gorillamotors

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I just found a roll of 24 gauge nichrome wire. Is this too big to be used for igniters? Or do I need to get some 30 gauge nichrome?
 
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