Old Copperhead Igniter Replacements

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Dave Pritts

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Had a chance to do some flying on a friend's farm yesterday. Great day IN Pa.! Attempted to use a couple of AT E15-4W motors I have had lying around for some time. The old copperhead igniters burned but didn't ignite the motors. Likely caused by improper installation for which I take full credit. ARGH!! Tried a couple "two wire" igniters from other AT motors I have but they didn't fit E15's nozzle. Question now is what igniters can I buy to fit those old E15 motors?

Thanx in advance for any suggestions
 

tomsteve

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or

 

BEC

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Don't be so fast to condemn the Copperhead or your technique. White Lightning oxidizes over time and becomes more and more difficult to light. You may need to find something you can run up inside the nozzle to scrape the propellant grain up near the top to expose some fresh surface....or almost no manner of igniter/initiator will get them lit..... :(
 

Dave Pritts

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Interesting.
I was made to understand that composites had an unlimited shelf life. Is oxidation confined to the White Lightning propellant or it common with other formulations as well?

Thanks for the re[ly.
 

dhbarr

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Interesting.
I was made to understand that composites had an unlimited shelf life. Is oxidation confined to the White Lightning propellant or it common with other formulations as well?
All compositions age, moreso when they're exposed to varying temperature & humidity. For instance, delay grains stored for many years in red reload kits often fail to function.

White reloads tend to swell & oxidize. For the one case you can peel back some of the casting tube, for the other a small stiff brush.
 

neil_w

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How long are we typically talking before the white lightnings oxidize? I have a few that are about 3-4 years old, am I in that territory yet? I guess there's no downside to scraping the inside of the core before loading up the igniter, but I'd prefer to have a proper idea of what's up.
 

Dave Pritts

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The E motors I had trouble with yesterday are 10+ years old but stored in. I've used several other F motors of the same vintage without issue.
I hope to pick some AT Jrs. to use at a club launch on the 12th. Taking all these suggestions/info into account I'll seek a solution and report findings after that weekend.
 

dhbarr

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How long are we typically talking before the white lightnings oxidize? I have a few that are about 3-4 years old, am I in that territory yet? I guess there's no downside to scraping the inside of the core before loading up the igniter, but I'd prefer to have a proper idea of what's up.
You can see it happening, they get a powdery scale and start to puff up a bit.
 

BEC

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Of course the OP was asking about a single use motor, in which it is harder to see what the condition of the grain is and also harder to do anything about it (any tool needs to go in through the nozzle and not mess the nozzle up and then you can't really see what you've done). With a reload you can see the oxidation and you can reach the slot to clean it.

I have some that are 10 years old that I have not gotten to light (but haven't tried again since taking the advice to scrape them off on the inside). One that was older was flown at the BMR launch last weekend. It took two igniters to go, and on the second one it chuffed at least half a dozen times before coming up to pressure enough to take the model (a LOC Weasel) on a very short flight which ended in an angled lawn dart landing and then an ejection that was strong enough to have the body yank the nose cone out of the ground. All very entertaining to watch. And being a heavy-duty LOC model, no significant damage occurred.
 

rharshberger

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Of course the OP was asking about a single use motor, in which it is harder to see what the condition of the grain is and also harder to do anything about it (any tool needs to go in through the nozzle and not mess the nozzle up and then you can't really see what you've done). With a reload you can see the oxidation and you can reach the slot to clean it.

I have some that are 10 years old that I have not gotten to light (but haven't tried again since taking the advice to scrape them off on the inside). One that was older was flown at the BMR launch last weekend. It took two igniters to go, and on the second one it chuffed at least half a dozen times before coming up to pressure enough to take the model (a LOC Weasel) on a very short flight which ended in an angled lawn dart landing and then an ejection that was strong enough to have the body yank the nose cone out of the ground. All very entertaining to watch. And being a heavy-duty LOC model, no significant damage occurred.
Too bad I wasn't there Bernard, I got some 30ga wire wrap wire igniters that fit 18mm reloads and have a BKNO3-V dip, they will darn near light dirt.
 

BEC

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That sounds like just the ticket. You may get a chance to help me with some old D10s and E15s yet... :D Thanks.
 

electricmatch

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Had a chance to do some flying on a friend's farm yesterday. Great day IN Pa.! Attempted to use a couple of AT E15-4W motors I have had lying around for some time. The old copperhead igniters burned but didn't ignite the motors. Likely caused by improper installation for which I take full credit. ARGH!! Tried a couple "two wire" igniters from other AT motors I have but they didn't fit E15's nozzle. Question now is what igniters can I buy to fit those old E15 motors?

Thanx in advance for any suggestions
we have a list of rocket igniters here. as long as you can supply a constant 12 volts, the composites would be the way to go.

 

dpower

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How long are we typically talking before the white lightnings oxidize? I have a few that are about 3-4 years old, am I in that territory yet? I guess there's no downside to scraping the inside of the core before loading up the igniter, but I'd prefer to have a proper idea of what's up.
IMHO, yes. Every year since manufacture, they’re going to oxidize more. Unless I’ve purchased one in the current year, and it has a recent date code, I’ll sand the slot/core of reloads, or try to scrape SU slots with a stiff wire.
 
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