What size wire for igniters?

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What size of wire do you use your igniter/initiator blanks?

  • 22 AWG

    Votes: 5 25.0%
  • 24 AWG

    Votes: 6 30.0%
  • 26AWG

    Votes: 2 10.0%
  • 28 AWG

    Votes: 2 10.0%
  • 30 AWG

    Votes: 3 15.0%
  • I buy my igniters pre- made.

    Votes: 7 35.0%
  • Something else

    Votes: 1 5.0%

  • Total voters
    20

cwbullet

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What size of wire do you use for your igniter/initiator blanks?
 

DragonRocketry

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Should allow multi answers. I use different sizes based on what they are for. I use 32ga for 18mm - 24mm, 26 ga for E - G and 24 for H and up.
 
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cwbullet

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good input thanks.
 

OKTurbo

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I use scrap cat5 cable. there are several pairs of wire in there. Not sure of the gauge, but it works great. The ignitors I’ve made are end wrapped with nichrome then dipped in pyrogen.
 

prfesser

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I like 26 ga four-conductor telephone wire for the leadwires. Hard to find these days. It's a bit smaller than most CAT-5 cable and is good for small motors.
 

Steve Shannon

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jsdemar

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I use 24-gauge "shooters wire" for smaller motors (G-I mostly).

For larger motors I used 22-gauge solid twisted pair... it flexes less when installing into the core.

For really big motors I used solid 18-gauge "thermostat" wire. Thick brown jacket, very stiff. No support "stick" needed.

igniter_wire.png
 

cwbullet

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I use 24-gauge "shooters wire" for smaller motors (G-I mostly).

For larger motors I used 22-gauge solid twisted pair... it flexes less when installing into the core.

For really big motors I used solid 18-gauge "thermostat" wire. Thick brown jacket, very stiff. No support "stick" needed.

View attachment 468728
Great photo. I have a bunch of 18 gauge shooter wire I got in an auction. I might use it for big motors.
 

SharkWhisperer

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I'm only LPR/MPR, and use 34 or 40 g nichrome for Aerotech E-G and all bp motors. Pyrogen that's always suitable for APCP fits and fires up anything BP, too. Why'd you stop the options at 30 gauge? My standard shooter's wire is 24 gauge (4 pairs) pulled from CAT5E cable. Could go smaller for small nozzles, but those instances, I just soup up the ridiculous Solar Starters with actual hot pyrogen for decent functionality, after washing off the glue/cornstarch nonsense.
 

hanabi

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22g, got a great deal on a 10,000 foot roll from Seminole Wire about 30 years ago.
Still have some.

1623675737633.png
 
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Rocketjunkie

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Ematch wire is 22 gauge solid. I use 30 gauge wire wrap wire for small igniters (13 and 18 mm Rx) They easily fit a .06" nozzle. I haven't found anything that will fit a .016" nozzle (end burning Micro-Maxx motors). Could get a full 1/4A with composite propellant (1/4A.3-3):)
 

SharkWhisperer

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Ematch wire is 22 gauge solid. I use 30 gauge wire wrap wire for small igniters (13 and 18 mm Rx) They easily fit a .06" nozzle. I haven't found anything that will fit a .016" nozzle (end burning Micro-Maxx motors). Could get a full 1/4A with composite propellant (1/4A.3-3):)
Terry (Prfessr) gifted me a sample of his super thin magnet wire (thank you!). Not sure what the gauge is, but that stuff is super thin. For me I need the magnifier on my helping hands just to remove the insulation (with fine sandpaper) and have yet to attach nichrome.

Here's a link to an example of 38 gauge wire that for sure would fit into an 0.016" nozzle. It's stated diameter is "0.0048 (with insulation), 0.004 (no insulation)"! https://www.amazon.com/TEMCo-AWG-Copper-Magnet-Wire/dp/B00LV90W6Q/ref=sxin_9_trr_310354011_2?cv_ct_cx=magnet+wire&dchild=1&keywords=magnet+wire&pd_rd_i=B00LV909HI&pd_rd_r=d4947656-6347-4076-be50-74a8f02b0d16&pd_rd_w=J97H0&pd_rd_wg=FoOFO&pf_rd_p=9e83fe05-f489-4685-b4af-0db60cbe7c15&pf_rd_r=7C59X996HB05K3X1B1H4&qid=1623816392&sr=1-3-5519553e-2baa-451e-af83-b0156e5c6669&th=1&tag=forumyield-20

If that 38 gauge wire is somehow too thick for ya, I also saw a 42 gauge roll that's 0.0026" in diameter unstripped. A 1-lb roll is 9.5 miles long and costs $30, and should be enough for a few igniters (if you can find them again after you build them). That's about as skinny as the thinnest human hair. https://www.amazon.com/Remington-In...gnet+wire&qid=1623816978&s=industrial&sr=1-30

Now that 42 gauge wire, even doubled-up, could probably fit up a mosquito's backdoor!

(they also sell an 80,000 foot 1-lb roll of 44 gauge...$37).
 
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cwbullet

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Terry (Prfessr) gifted me a sample of his super thin magnet wire (thank you!). Not sure what the gauge is, but that stuff is super thin. For me I need the magnifier on my helping hands just to remove the insulation (with fine sandpaper) and have yet to attach nichrome.

Here's a link to an example of 38 gauge wire that for sure would fit into an 0.016" nozzle. It's stated diameter is "0.0048 (with insulation), 0.004 (no insulation)"! https://www.amazon.com/TEMCo-AWG-Copper-Magnet-Wire/dp/B00LV90W6Q/ref=sxin_9_trr_310354011_2?cv_ct_cx=magnet+wire&dchild=1&keywords=magnet+wire&pd_rd_i=B00LV909HI&pd_rd_r=d4947656-6347-4076-be50-74a8f02b0d16&pd_rd_w=J97H0&pd_rd_wg=FoOFO&pf_rd_p=9e83fe05-f489-4685-b4af-0db60cbe7c15&pf_rd_r=7C59X996HB05K3X1B1H4&qid=1623816392&sr=1-3-5519553e-2baa-451e-af83-b0156e5c6669&th=1&tag=forumyield-20

If that 38 gauge wire is somehow too thick for ya, I also saw a 42 gauge roll that's 0.0026" in diameter unstripped. A 1-lb roll is 9.5 miles long and costs $30, and should be enough for a few igniters (if you can find them again after you build them). That's about as skinny as the thinnest human hair. https://www.amazon.com/Remington-In...gnet+wire&qid=1623816978&s=industrial&sr=1-30

Now that 42 gauge wire, even doubled-up, could probably fit up a mosquito's backdoor!

(they also sell an 80,000 foot 1-lb roll of 44 gauge...$37).
I have a crapload of 26 and 28 gauge kynar wire to use for igniters. It is small enough for every igniter use I can imagine.
 

Mike Haberer

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I use scrap cat5 cable. there are several pairs of wire in there. Not sure of the gauge, but it works great. The ignitors I’ve made are end wrapped with nichrome then dipped in pyrogen.
Cat5 spec is 24 gauge.
 

bjphoenix

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It seems that if you get down to 30 gage then you are about the size of the nichrome.

I wonder what is the largest wire size that would be practical with a 24mm E18 reload.
 

waltr

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I have measured the 24/40 E18 nozzle at 0.101 inch.

I use lead from MJG Ematches (3' lead I cut to < foot for Dual deploy) which are 0.100" across the two conductors insulation (24ga solid wire inside) the make ignites. This just fits the E18 nozzle but does not fit after dipped in pyrogen. Using Quickburst ProCast pyrogen.

Recently made some igniters with 30ga wire wrap wire and 40ga nichrome. Have tested one on a Qjet C18W and it lit the motor quickly. So this small of wire and nichrome works.
This 30ga wire will fit in the small motors like the AT 18/20 D13W which has a nozzle of 0.076" diameter and the Qjets.

You need to measure the diameter of the insulated wire, insulation thickness can vary, to ensure that after adding pyrogen it fit in the 0.101" nozzle.
Probably 26ga solid wire will fit but 28 or 30ga will fit.
 
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