Found Head-End Ignition Closures

[Viperfixr]

I am interested in any head end ignition closures, for either CTI or Aerotech motors, in any size 29-75mm--whatever you have for sale. Please just PM me with what you have. Thanks!

 

[Viperfixr]

Bump

 

[Cl(VII)]

I suspect you did, but did you check with Crazy Jim?

 

[Mendal]

Does anyone have drawings or specs on these? I know its not an official closure but I'm just curious how others have achieved this? any good photos out there? I searched the forum but came up empty for the most part.

 

[Steve Shannon]

Does anyone have drawings or specs on these? I know its not an official closure but I'm just curious how others have achieved this? any good photos out there? I searched the forum but came up empty for the most part.

Following the accidents that happened at BALLS this year I don’t recommend head end ignition. Everything you want to do can be done more safely with an igniter inserted from the bottom, even in an upper stage.

 

[MClark]

Aerotech was selling an HEI a few years ago

 

[rharshberger]

Aerotech was selling an HEI a few years ago

They still have it listed on their RCS website iirc.

 

[dshmel]

They still have it listed on their RCS website iirc.

It also says: NOTE: This is a single-use device and a new initiator must be used for each motor firing.

https://www.rocketmotorparts.com/Low_Cost_Head_End_Initiator/p1577809_16501656.aspx

 

[Steve Shannon]

It also says: NOTE: This is a single-use device and a new initiator must be used for each motor firing.

All initiators are single use.
The Aerotech head end ignition system is the only one that I know of that permits adding the initiator after the motor has been completely assembled. That’s an improvement over those that require the initiator be in the motor the entire time the motor is assembled, but only if the user leaves the initiator out until the last possible moment.
The HEI forward closure is reusable.

 

[Hybrid33]

Is the forward closure available ?

 

[Viperfixr]

I suspect you did, but did you check with Crazy Jim?

I did...the production run finished long ago with no extras lying around.

 

[Viperfixr]

bump...any AT or CTI HEI forward closures sale?? Especially 75 or 54mm.

 

[cwbullet]

Following the accidents that happened at BALLS this year I don’t recommend head end ignition. Everything you want to do can be done more safely with an igniter inserted from the bottom, even in an upper stage.

What happened at Balls?

 

[Steve Shannon]

What happened at Balls?

A flyer using copper thermite in a head end ignition system accidentally ignited a pretty good size motor thru static discharge (we strongly believe). He received a helicopter ride to a burn center in California. Fortunately his burns were less than originally thought. There’s several posts talking about it on TRF. I’m sure you saw them at the time. It’s just harder to avoid some kinds of accidents when using head end ignition. You’re working with a motor with its igniter already inserted.

 

[FredA]

"It’s just harder to avoid some kinds of accidents when using head end ignition."

Everything is harder than not really trying to be safe.....
Let's not throw the baby out with the dirty bathwater, please.

 

[numbo]

The amateur tech for HEI is poor because they are so rare. If a few were made using the tech commercial motors use the techniques would start to spread. Even the most basic mechanical interrupts would be an improvement.

 

[Banzai88]

The amateur tech for HEI is poor because they are so rare. If a few were made using the tech commercial motors use the techniques would start to spread. Even the most basic mechanical interrupts would be an improvement.

That's a similar sentiment to the current revitalisation on 2 stages: Better tech is cheaper, widely avaliable, alway improving, and getting safer for the new user and ground based personnel all the time.