Copperhead igniter into Econojet F20 - hard to fit in, help please

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billdz

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I've been using Aerotech motors and have used Copperhead igniters but this is the first time I've tried the Econojet. I've been fiddling with the igniter and it just does not want to go in. I've found the slot and was able to stick a piece of wire all the way up, but the igniter head seems too thick. I've tried 3 different igniters, all the same.

What am I doing wrong? It's not possible to remove the nozzle to have a look inside, is it?
 
Nozzle looks OK. The hole in the nozzle is so small I can't see the slot with my eyes, an exacto would not fit.
 
Do these igniters normally slide in easily? I can't get either igniter into either of the 2 Econojet motors in the pack. Never before had a problem sliding an igniter into a motor. Either there is something wrong with these motors or I am seriously brain dead.
 
Are you using Copperheads or the First Fire ignitors that came with the Econojets? I pulled an Econojet F-20 from my motor stash and tried putting in the First Fire ignitor. Not too much of a problem but the rectangular slot may not be exactly aligned with the circular nozzle hole. Use a flashlight to see how the slot aligns with the nozzle, and angle in the ignitor slightly if necessary. The Copperhead is wider, but was able to fit both the Copperhead and First Fire in the F20:
IMG_20181214_184222.jpg IMG_20181214_184258.jpg
 
I bought a G64 reload once and the copperhead that came with it had way too big of a head on it and it wouldn't fit in the grain slots at all. Ended up using a first fire jr to launch it and I trashed the copperhead. I'd suggest just buying a set of first fire jr's.
 
It is a copperhead igniter, I have used them with G motors with no issue. I cannot see the slot, even with a flashlight.Econojet.jpg
 
Is it my imagination or does that throat look like it is blocked by the same plastic that the nozzle is molded out of? Could be some flashing (plastic that is not actually part of the molded part) that is a result of the casting process. Should only be wafer-thin if that is the situation. Other opinions? I don't normally use these.

EDIT: Thought I'd seen something like this a while back. The smaller reloads (for example RMS 18/20) state in the instructions:
Fig-5: Using the point of a pencil, remove any plastic “flashing”
that may remain in the nozzle throat. Insert the nozzle into the
open end of the case, with the igniter lead threaded through the
nozzle throat, until the nozzle is seated against the liner.


I would say the nozzle in the Econojet is formed similarly and suffers similar issues, they just have not mentioned it in the instructions I guess. Have a close look and you should be able to see the grain inside, not just the plastic at the throat.
 
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OK, I'm thinking either excessive flashing over the nozzle opening or a defective/incorrectly assembled motor from the factory. How were you able to get the wire all the way up? Is there a small hole? I know that on the RMS motors sometimes I have to widen the nozzle hole because it's either completely or partially blocked by the flashing. As mentioned, you can use a long tipped exacto knife and twirl to widen the nozzle hole and remove excess flashing.
Here's what it should look like:
IMG_20181214_231918.jpg

EDIT: Looks like Over the Top beat me to the post.
 
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You have a blocked nozzle, an occasional occurrence with any Aerotech motor in my experience. The partial or full blockage is usually pretty thin and I'll ream it out with a pencil or small awl. If using a knife you must take care not to deform or enlarge the hole. After that operation you should be good to go. Sometimes you'll get a copperhead with a large amount of pyrogen at the tip that wont fit in the hole. If I don't have another igniter to try I will take an emory board to it and remove some material until it fits.
 
Was the copperhead you are trying to use packaged with the motor? I could be wrong, my wife points that out often ;) , but I think copperheads used to come in different widths. I have not used them in years but I know that the regular sized ones would not fit into some of the smaller nozzles and the c-slot motors were difficult to insert even with the proper size.
 
That definitely looks like throat is blocked by some of the phenolic flashing. Clearing the throat is not mentioned in the instructions for single use motors because it should have been done at Aerotech when the motor was assembled, but it’s a simple matter to just poke through it with a sharp pencil, skewer, hobby knife, etc.
 
Thanks for the replies. The throat is clear, appears to be an issue with the slot. I took the motors with me to today's launch but the local experts could not figure out what is wrong. These are the copperheads included with the motors, the package was just recently opened but the motors are old.
 
Slot is clear, you can see propellant..Slot is offset to side & hard to get to.
Must go in at hard angle with igniter...try using the opposite end of pyrogen to to find slot & insert to see if clear.
The turn it around and insert pyro end.
 
If it came with a copperhead, it's OLD! If there is white stuff on the propellant, it's likely the propellant has swollen and the igniter may not go in. White Lightning propellant is the only Aerotech propellant with this problem. Redline doesn't swell but gets very hard to ignite when old.
 
I'm buying Rocketjunkie's swollen propellant theory, this is old stock, but never previously opened package. As requested by bjphoenix, I'm posting another pic. The copperheads are definitely not going in, will have to try a first fire igniter.motor.jpg
 
Is the F20 a slotted grain? Looks like it from pic. If so, think you just have to use some finesse to install copper head.
 
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